Journal articles: 'Semiconductor doping'

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Zeng, Yan, Guangchao Han, and Yuanping Yi. "Impact of n-Doping Mechanisms on the Molecular Packing and Electron Mobilities of Molecular Semiconductors for Organic Thermoelectrics." Organic Materials 4, no. 01 (January 2022): 1–6. http://dx.doi.org/10.1055/a-1729-5728.

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Electrical conductivity is one of the key parameters for organic thermoelectrics and depends on both the concentration and mobility of charge carriers. To increase the carrier concentration, molecular dopants have to be added into organic semiconductor materials, whereas the introduction of dopants can influence the molecular packing structures and hence carrier mobility of the organic semiconductors. Herein, we have theoretically investigated the impact of different n-doping mechanisms on molecular packing and electron transport properties by taking (4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl)dimethylamine (N-DMBI-H) and quinoid-dicyanomethylene-dipyrrolo-[3,4-c]pyrrole-1,4-diylidene)bis(thieno[3,2-b]thiophene (Q-DCM-DPPTT) respectively as representative n-dopant and molecular semiconductor. The results show that when the doping reactions and charge transfer spontaneously occur in the solution at room temperature, the oppositely charged dopant and semiconductor molecules will be tightly bound to disrupt the semiconductor to form long-range molecular packing, leading to a substantial decrease of electron mobility in the doped film. In contrast, when the doping reactions and charge transfer are activated by heating the doped film, the molecular packing of the semiconductor is slightly affected and hence the electron mobility remains quite high. This work indicates that thermally activated n-doping is an effective way to achieve both high carrier concentration and high electron mobility in n-type organic thermoelectric materials.

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Khramtsov, Igor A., and Dmitry Yu Fedyanin. "Superinjection of Holes in Homojunction Diodes Based on Wide-Bandgap Semiconductors." Materials 12, no. 12 (June 19, 2019): 1972. http://dx.doi.org/10.3390/ma12121972.

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Electrically driven light sources are essential in a wide range of applications, from indication and display technologies to high-speed data communication and quantum information processing. Wide-bandgap semiconductors promise to advance solid-state lighting by delivering novel light sources. However, electrical pumping of these devices is still a challenging problem. Many wide-bandgap semiconductor materials, such as SiC, GaN, AlN, ZnS, and Ga2O3, can be easily n-type doped, but their efficient p-type doping is extremely difficult. The lack of holes due to the high activation energy of acceptors greatly limits the performance and practical applicability of wide-bandgap semiconductor devices. Here, we study a novel effect which allows homojunction semiconductor devices, such as p-i-n diodes, to operate well above the limit imposed by doping of the p-type material. Using a rigorous numerical approach, we show that the density of injected holes can exceed the density of holes in the p-type injection layer by up to four orders of magnitude depending on the semiconductor material, dopant, and temperature, which gives the possibility to significantly overcome the doping problem. We present a clear physical explanation of this unexpected feature of wide-bandgap semiconductor p-i-n diodes and closely examine it in 4H-SiC, 3C-SiC, AlN, and ZnS structures. The predicted effect can be exploited to develop bright-light-emitting devices, especially electrically driven nonclassical light sources based on color centers in SiC, AlN, ZnO, and other wide-bandgap semiconductors.

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Liu, Ting, Chen Li, Beilei Yuan, Yang Chen, Haoming Wei, and Bingqiang Cao. "Dopant compensation in p-type doped MAPb₁₋_xCu_xI₃ alloyed perovskite crystals." Applied Physics Letters 121, no. 1 (July 4, 2022): 012102. http://dx.doi.org/10.1063/5.0095370.

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Tuning the optical and electrical properties of semiconductors by designed doping is the basis of most energy-related semiconductor optoelectronic devices. In this Letter, we report the dopant compensation effect of P-type doped MAPb1− x Cu xI3 alloyed perovskite crystals. MAPb1− xCu xI3 single crystals were prepared by the inverse temperature crystallization method using cupric chloride (CuCl2) as the doping source. By XRD, XPS, STEM, and photoluminescence (PL) spectra analyses, we demonstrate that the doped cupric (Cu2+) ions can partially substitute lead (Pb2+) ions and form Cu–Pb based crystal semiconductor alloys of MAPb1− xCu xI3 with tunable bandgap by controlling the Pb/Cu ratio. More detailed XPS analysis of the doped crystal shows that the Cu2+ ions in MAPb1− xCu xI3 are partially reduced by I− ions, and the coexistence of two valence states of Cu species (Cu2+ and Cu+) was observed in the doped crystals. Hall results of MAPb1− xCu xI3 semiconductors show that the presence of reduced Cu+ ions impels the change of conductive type from weak N-type to P-type obviously, while the resistivity of doped MAPb1− xCu xI3 increases significantly from 104 to 107 Ω cm. The defect-related optical fingerprints of cupric doped crystals were investigated in detail by temperature-dependent PL spectroscopy. The pristine MAPbI3 perovskite crystal exhibits intrinsic donor bound exciton (D0X) luminescence at low temperature (10 K), while the doped MAPb1− xCu xI3 perovskites exhibit donor-acceptor or bound exciton (A0X) peaks related to a Cu+ dopant in sequence with the increase in the Cu ion content. These results indicate that the doping of Cu2+/+ ions into the MAPb1− xCu xI3 crystal not only changes the semiconductor bandgap but also causes the dopant compensation.

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Lee, Hyeonju, Xue Zhang, Bokyung Kim, Jin-Hyuk Bae, and Jaehoon Park. "Effects of Iodine Doping on Electrical Characteristics of Solution-Processed Copper Oxide Thin-Film Transistors." Materials 14, no. 20 (October 15, 2021): 6118. http://dx.doi.org/10.3390/ma14206118.

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In order to implement oxide semiconductor-based complementary circuits, the improvement of the electrical properties of p-type oxide semiconductors and the performance of p-type oxide TFTs is certainly required. In this study, we report the effects of iodine doping on the structural and electrical characteristics of copper oxide (CuO) semiconductor films and the TFT performance. The CuO semiconductor films were fabricated using copper(II) acetate hydrate as a precursor to solution processing, and iodine doping was performed using vapor sublimated from solid iodine. Doped iodine penetrated the CuO film through grain boundaries, thereby inducing tensile stress in the film and increasing the film’s thickness. Iodine doping contributed to the improvement of the electrical properties of the solution-processed CuO semiconductor including increases in Hall mobility and hole-carrier concentration and a decrease in electrical resistivity. The CuO TFTs exhibited a conduction channel formation by holes, that is, p-type operation characteristics, and the TFT performance improved after iodine doping. Iodine doping was also found to be effective in reducing the counterclockwise hysteresis in the transfer characteristics of CuO TFTs. These results are explained by physicochemical reactions in which iodine replaces oxygen vacancies and oxygen atoms through the formation of iodide anions in CuO.

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Erwin, Steven C., Lijun Zu, Michael I. Haftel, Alexander L. Efros, Thomas A. Kennedy, and David J. Norris. "Doping semiconductor nanocrystals." Nature 436, no. 7047 (July 2005): 91–94. http://dx.doi.org/10.1038/nature03832.

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Telford, Mark. "Doping semiconductor nanocrystals." Materials Today 8, no. 9 (September 2005): 10. http://dx.doi.org/10.1016/s1369-7021(05)71063-4.

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Kim, Dongwook, Hyeonju Lee, Bokyung Kim, Sungkeun Baang, Kadir Ejderha, Jin-Hyuk Bae, and Jaehoon Park. "Investigation on Atomic Bonding Structure of Solution-Processed Indium-Zinc-Oxide Semiconductors According to Doped Indium Content and Its Effects on the Transistor Performance." Materials 15, no. 19 (September 29, 2022): 6763. http://dx.doi.org/10.3390/ma15196763.

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The atomic composition ratio of solution-processed oxide semiconductors is crucial in controlling the electrical performance of thin-film transistors (TFTs) because the crystallinity and defects of the random network structure of oxide semiconductors change critically with respect to the atomic composition ratio. Herein, the relationship between the film properties of nitrate precursor-based indium-zinc-oxide (IZO) semiconductors and electrical performance of solution-processed IZO TFTs with respect to the In molar ratio was investigated. The thickness, morphological characteristics, crystallinity, and depth profile of the IZO semiconductor film were measured to analyze the correlation between the structural properties of IZO film and electrical performances of the IZO TFT. In addition, the stoichiometric and electrical properties of the IZO semiconductor films were analyzed using film density, atomic composition profile, and Hall effect measurements. Based on the structural and stoichiometric results for the IZO semiconductor, the doping effect of the IZO film with respect to the In molar ratio was theoretically explained. The atomic bonding structure by the In doping in solution-processed IZO semiconductor and resulting increase in free carriers are discussed through a simple bonding model and band gap formation energy.

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Caccamo, Sebastiano, and Rosaria Anna Puglisi. "Carbon-Free Solution-Based Doping for Silicon." Nanomaterials 11, no. 8 (August 5, 2021): 2006. http://dx.doi.org/10.3390/nano11082006.

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Molecular doping is a method to dope semiconductors based on the use of liquid solutions as precursors of the dopant. The molecules are deposited on the material, forming a self-ordered monolayer that conforms to the surfaces, whether they are planar or structured. So far, molecular doping has been used with precursors of organic molecules, which also release the carbon in the semiconductor. The carbon atoms, acting as traps for charge carriers, deteriorate the doping efficiency. For rapid and extensive industrial exploitation, the need for a method that removes carbon has therefore been raised. In this paper, we use phosphoric acid as a precursor of the dopant. It does not contain carbon and has a smaller steric footprint than the molecules used in the literature, thus allowing a much higher predetermined surface density. We demonstrate doses of electrical carriers as high as 3 × 1015 #/cm2, with peaks of 1 × 1020 #/cm3, and high repeatability of the process, indicating an outstanding yield compared to traditional MD methods.

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Tavkhelidze, Avtandil, Larissa Jangidze, Zaza Taliashvili, and Nima E. Gorji. "G-Doping-Based Metal-Semiconductor Junction." Coatings 11, no. 8 (August 7, 2021): 945. http://dx.doi.org/10.3390/coatings11080945.

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Geometry-induced doping (G-doping) has been realized in semiconductors nanograting layers. G-doping-based p-p(v) junction has been fabricated and demonstrated with extremely low forward voltage and reduced reverse current. The formation mechanism of p-p(v) junction has been proposed. To obtain G-doping, the surfaces of p-type and p+-type silicon substrates were patterned with nanograting indents of depth d = 30 nm. The Ti/Ag contacts were deposited on top of G-doped layers to form metal-semiconductor junctions. The two-probe method has been used to record the I–V characteristics and the four-probe method has been deployed to exclude the contribution of metal-semiconductor interface. The collected data show a considerably lower reverse current in p-type substrates with nanograting pattern. In the case of p+-type substrate, nanograting reduced the reverse current dramatically (by 1–2 orders of magnitude). However, the forward currents are not affected in both substrates. We explained these unusual I–V characteristics with G-doping theory and p-p(v) junction formation mechanism. The decrease of reverse current is explained by the drop of carrier generation rate which resulted from reduced density of quantum states within the G-doped region. Analysis of energy-band diagrams suggested that the magnitude of reverse current reduction depends on the relationship between G-doping depth and depletion width.

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10

Xu, Zhichao. "Research On Mg Doping in Nitride Semiconductor Materials." Highlights in Science, Engineering and Technology 71 (November 28, 2023): 254–58. http://dx.doi.org/10.54097/hset.v71i.12707.

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Summarized the achievements of various model research directions in nitride Mg doped semiconductors in this thesis. Due to the Internal properties of Mg acceptors which resulting the low ionization rate of acceptor, and the low hole mobility in heavily Mg doped nitrides, the conductivity of Mg doped nitrides is limited. At present, research is divided into three categories of models, one is a new type of polarization model. This model adopts a built-in electron polarization ionization acceptor dopant in the bulk uniaxial semiconductor crystal, and provides an attractive solution for the problem of P-type and n-type doping in broadband gap semiconductors. The other two are the traditional thermal activation model. There are mainly ultra-high-pressure-annealing (UHPA) and multicycle rapid thermal annealing (MRTA) respectively. Both of these schemes can activate more Mg impurities, resulting in higher conductivity in nitrides. The principles, advantages and disadvantages, and future development prospects will be explained of these three models in this thesis.

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Chakrapani, Vidhya. "(Invited) Universal Alignment of Surface and Bulk Oxygen Levels in Semiconductors." ECS Meeting Abstracts MA2023-01, no. 32 (August 28, 2023): 1820. http://dx.doi.org/10.1149/ma2023-01321820mtgabs.

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Lattices of most semiconductors have a large density of intrinsic and extrinsic defects which gives rise to effects such as surface Fermi level (EF) pinning, dopant compensation, asymmetrical p versus n-doping, and device degradation. Oxygen and hydrogen are the two most important impurities in semiconductors because of their ubiquitous presence in growth and device processing environments and consequently their incorporation strongly influences electronic and electrical properties. Therefore, a deeper understanding of the interaction of these species with the semiconductor surface and bulk defects is necessary for enabling the development of devices based on them such as photovoltaic and photocatalytic systems, fuel cells, and many others. Analysis of the reported surface work function values and the substitutional bulk O-defect energies show that the surface Fermi level of position in a broad range of group IV, III-V, II-VI, and I-III-VI2 semiconductors with physisorbed O2 lies universally at approximately -5.1 eV below the vacuum level. Similarly, results show that the energy of the bulk substitutional O-related amphoteric defects incorporated during crystal growth also has a universal energy of ~ -5.0 eV with respect to the vacuum level for most of the investigated semiconductors. It is shown that the process of ‘surface transfer doping’ that involves an adsorbed nanoscale water film on the semiconductor surface is likely responsible for the universal alignment of oxygen levels. Figure 1

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12

Gösele, Ulrich M., and Teh Y. Tan. "Point Defects and Diffusion in Semiconductors." MRS Bulletin 16, no. 11 (November 1991): 42–46. http://dx.doi.org/10.1557/s0883769400055512.

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Semiconductor devices generally contain n- and p-doped regions. Doping is accomplished by incorporating certain impurity atoms that are substitutionally dissolved on lattice sites of the semiconductor crystal. In defect terminology, dopant atoms constitute extrinsic point defects. In this sense, the whole semiconductor industry is based on controlled introduction of specific point defects. This article addresses intrinsic point defects, ones that come from the native crystal. These defects govern the diffusion processes of dopants in semiconductors. Diffusion is the most basic process associated with the introduction of dopants into semiconductors. Since silicon and gallium arsenide are the most widely used semiconductors for microelectronic and optoelectronic device applications, this article will concentrate on these two materials and comment only briefly on other semiconductors.A main technological driving force for dealing with intrinsic point defects stems from the necessity to simulate dopant diffusion processes accurately. Intrinsic point defects also play a role in critical integrated circuit fabrication processes such as ion-implantation or surface oxidation. In these processes, as well as during crystal growth, intrinsic point defects may agglomerate and negatively impact the performance of electronic or photovoltaic devices. If properly controlled, point defects and their agglomerates may also be used to accomplish positive goals such as enhancing device performance or processing yield.

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MAJIDI, ROYA. "EFFECT OF DOPING ON THE ELECTRONIC PROPERTIES OF GRAPHYNE." Nano 08, no. 06 (November 18, 2013): 1350060. http://dx.doi.org/10.1142/s1793292013500604.

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We have used density functional theory to study the effect of doping on the electronic properties of graphyne. The graphyne with alpha type has been considered since it is analogous to graphene. The electronic properties of graphynes containing B , N or O impurity have been compared with those of pure graphyne. It is found that the electronic properties of alpha graphyne change from semimetal to semiconductor by doping. The B -doped graphyne becomes a p-type semiconductor, while N -doped and O -doped graphynes are n-type semiconductors. Our results provide possibility of opening an energy gap in graphyne as required for fabricating high-performance nanoelectronic devices based on graphyne.

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14

Cahen, David, and Igor Lubomirsky. "Percolation-Controlled Semiconductor Doping." Chemistry of Materials 10, no. 10 (October 1998): 2596–98. http://dx.doi.org/10.1021/cm9802954.

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15

Wallentin, Jesper, and Magnus T. Borgström. "Doping of semiconductor nanowires." Journal of Materials Research 26, no. 17 (August 22, 2011): 2142–56. http://dx.doi.org/10.1557/jmr.2011.214.

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16

Pramanik, Md Bappi, Md Abdullah Al Rakib, Md Abubakor Siddik, and Shorab Bhuiyan. "Doping Effects and Relationship between Energy Band Gaps, Impact of Ionization Coefficient and Light Absorption Coefficient in Semiconductors." European Journal of Engineering and Technology Research 9, no. 1 (January 18, 2024): 10–15. http://dx.doi.org/10.24018/ejeng.2024.9.1.3118.

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The doping process is very important in semiconductor technology that is widely used in the production of electronic devices. The effects of doping on the resistivity, mobility and energy band gap of semiconductors are significant and can greatly impact the performance of electronic devices. This thesis aims to investigate the impact of doping on the resistivity, mobility, energy band gap, impact of ionization coefficient, and light absorption coefficient of semiconductors. The study involves an in-depth analysis of the electronic properties of doped semiconductors and their behavior in various conditions. This thesis will provide a comprehensive understanding of the impact of doping on the electronic properties of semiconductors. The energy band gap, impact of ionization coefficient, and Light absorption coefficient were observed in this thesis. In the experimental result, the relation between energy band gap and atomic density, light absorption coefficient and atomic density, impact ionization and atomic density, impact ionization coefficient and Light absorption coefficient, resistivity and mobility has been found.

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Fortunato, Elvira, Alexandra Gonçalves, António Marques, Ana Pimentel, Pedro Barquinha, Hugo Águas, Luís Pereira, et al. "Multifunctional Thin Film Zinc Oxide Semiconductors: Application to Electronic Devices." Materials Science Forum 514-516 (May 2006): 3–7. http://dx.doi.org/10.4028/www.scientific.net/msf.514-516.3.

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In this paper we report some of the recent advances in transparent thin film oxide semiconductors, specifically zinc oxide (ZnO), produced by rf magnetron sputtering at room temperature with multifunctional properties. By controlling the deposition parameters it is possible to produce undoped material with electronic semiconductor properties or by doping it to get either n-type or p-type semiconductor behavior. In this work we refer our experience in producing n-type doping ZnO as transparent electrode to be used in optoelectronic applications such as solar cells and position sensitive detectors while the undoped ZnO can be used as UV photodetector or ozone gas sensor or even as active layer of fully transparent thin film transistors.

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Jin, Lun, Danrui Ni, Xin Gui, Daniel B. Straus, Qiang Zhang, and Robert J. Cava. "Magnetic cations doped into a double perovskite semiconductor." Journal of Materials Chemistry C 10, no. 8 (2022): 3232–40. http://dx.doi.org/10.1039/d1tc05585b.

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19

Yu, Chenxi. "Analysis on the Electrostatic Doping and Several Alternative Devices." Journal of Physics: Conference Series 2248, no. 1 (April 1, 2022): 012014. http://dx.doi.org/10.1088/1742-6596/2248/1/012014.

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Abstract With the development of semiconductor technology, the size of precision instruments is becoming more and more stringent. The purpose of electrostatic doping is to provide a possibility on nanoscale semiconductor devices and to replace chemical doping, it also replaces donor/receptor doping with Gate-Induced free electron/hole charges in ultra-thin MOS (Metal-Oxide-Semiconductor) structures, and provide some areas with high electron/hole density in semiconductor devices. This paper introduces Electrostatic Doping methods and Several Alternative Devices, emphasizing the functions of metal and semiconductor operation functions, energy band gaps and applied electric fields, and their interaction in induced ED. In addition, this paper discusses the advantages of ED devices and the major potential obstacles to future CMOs, and the modeling and experimental implementation of this approach will help to implement and evaluate the possibility of replacing traditional doping methods for innovative devices for future CMOs.

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Du, Mao-Hua, Steven C. Erwin, and Al L. Efros. "Trapped-Dopant Model of Doping in Semiconductor Nanocrystals." Nano Letters 8, no. 9 (September 10, 2008): 2878–82. http://dx.doi.org/10.1021/nl8016169.

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On, Vo Van, J. Guerrero-Sanchez, and D. M. Hoat. "Controlling magnetic-semiconductor properties of the Si- and Al-doped blue phosphorene monolayer." Journal of Physics D: Applied Physics 55, no. 16 (January 26, 2022): 165302. http://dx.doi.org/10.1088/1361-6463/ac49b4.

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Abstract Doping has been widely employed as an efficient method to diversify a materials properties. In this work, the structural, magnetic, and electronic properties of pristine aluminum (Al)-, and silicon (Si)-doped blue phosphorene monolayer are investigated using first-principles calculations. Pristine monolayer is a non-magnetic, wide gap, semiconductor with a band gap of 1.81 eV. The 1Si-doped system is a ferromagnetic semiconductor. However, the magnetism is turned off when increasing the dopant composition with small Si–Si distance. Further separating the dopants recovers, step by step, the magnetic properties and an antiferromagnetic (AFM)-ferromagnetic (FM) state transition will take place at large dopants separation. In contrast, Al doping retains the non-magnetic semiconductor behavior of blue phosphorene. However, significant energy gap reduction is achieved, where this parameter exhibits a strong dependence on the dopant concentration and doping configuration. Such control may also induce the indirect-direct gap transition. Our results introduce prospective two-dimensional (2D) materials for application in spintronic and optoelectronic nano devices, which can be realized and stabilized in experiments as suggested by the calculated formation and cohesive energies.

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Larson, Lawrence A., Justin M. Williams, and Michael I. Current. "Ion Implantation for Semiconductor Doping and Materials Modification." Reviews of Accelerator Science and Technology 04, no. 01 (January 2011): 11–40. http://dx.doi.org/10.1142/s1793626811000616.

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In the 50-plus years since the patent was issued to William Shockley in 1957, ion implantation has become a key process in the commercial production of semiconductor devices, advanced engineering materials and photonic devices. This article reviews the fundamental concepts of production ion implanters for both the processes used in manufacturing and also in the design of the tools themselves. Recent publications in the application areas of semiconductors and materials modification are summarized, focusing on the attendant process effects. These results demonstrate that ion implantation is a well understood technology with abundant and evolving applications.

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Robertson, John, and Zhaofu Zhang. "Doping limits in p-type oxide semiconductors." MRS Bulletin 46, no. 11 (November 2021): 1037–43. http://dx.doi.org/10.1557/s43577-021-00211-3.

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AbstractThe ability to dope a semiconductor depends on whether the Fermi level can be moved into its valence or conduction bands, on an energy scale referred to the vacuum level. For oxides, there are various suitable n-type oxide semiconductors, but there is a marked absence of similarly suitable p-type oxides. This problem is of interest not only for thin-film transistors for displays, or solar cell electrodes, but also for back-end-of-line devices for the semiconductor industry. This has led to a wide-ranging search for p-type oxides using high-throughput calculations. We note that some proposed p-type metal oxides have cation s-like lone pair states. The defect energies of some of these oxides were calculated in detail. The example SnTa2O6 is of interest, but others have structures more closely based on perovskite structure and are found to have more n-type than p-type character. Graphic abstract

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Lozovskiy, V. N., B. M. Seredin, and N. Yu Arkhipova. "Local Doping of Semiconductor Crystals by Thermomigration." Materials Science Forum 843 (February 2016): 46–51. http://dx.doi.org/10.4028/www.scientific.net/msf.843.46.

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The article includes the analysis of the features related to local doping of silicon using electrically active doping agents by thermomigration of binary and ternary liquid zones as compared to doping by diffusion. The concentration range of doping by binary zone migration is found to be substantially narrower than that of doping by diffusion. Introduction of a third component to the liquid phase ena-bles expansion of the thermomigration doping range to the values exceeding the diffusion doping range by the same doping agent. For silicon crystals, this technological feature of thermomigration is produced by using GaxAl1-xSi and SnxAl1-xSi ternary zones. The crystal doping rate by thermomigration in techno-logically relevant situations was shown to exceed the rate of diffusion doping by orders of magnitude. The layers doped by thermomigration of stably moving liquid zones are structurally more perfect than diffusion layers.

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Su, Xiao-Qian, and Xue-Feng Wang. "Electronic and Spintronic Properties of Armchair MoSi2N4 Nanoribbons Doped by 3D Transition Metals." Nanomaterials 13, no. 4 (February 9, 2023): 676. http://dx.doi.org/10.3390/nano13040676.

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Structural and physical properties of armchair MoSi2N4 nanoribbons substitutionally doped by 3d transition metals (TM) at Mo sites are investigated using the density functional theory combined with the non-equilibrium Green’s function method. TM doping can convert the nonmagnetic direct semiconductor into device materials of a broad variety, including indirect semiconductors, half semiconductors, metals, and half metals. Furthermore the 100% spin filtering behavior in spin-up and spin-down half metals, a negative differential resistance with peak-to-valley ratio over 140 and a rectification effect with ratio over 130 are predicted, as well as semiconductor behavior with high spin polarization.

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Si, Yuan, Hao-Ming Yang, Hong-Yu Wu, Wei-Qing Huang, Ke Yang, Ping Peng, and Gui-Fang Huang. "Tuning the near-gap electronic structure of Cu2O by anion–cation co-doping for enhanced solar energy conversion." Modern Physics Letters B 31, no. 01 (January 10, 2017): 1650429. http://dx.doi.org/10.1142/s0217984916504297.

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Doping is an effective strategy to tune the electronic properties of semiconductors, but some side effects caused by mono-doping degrade the specific performance of matrixes. As a model system to minimize photoproduced electron-hole pairs recombination by anion–cation co-doping, we investigate the electronic structures and optical properties of (Fe[Formula: see text]+[Formula: see text]N) co-doped Cu2O using the first-principles calculations. Compared to the case of mono-doping, the Fe[Formula: see text]N[Formula: see text] (a Fe (N) atom substituting a Cu (O) atom) co-doping reduces the energy cost of doping as a consequence of the charge compensation between the iron and nitrogen impurities, which eliminates the isolated levels (induced by mono-dopant) in the band gap. Interestingly, it is found that the contributions of different host atoms (Cu and O) away from anion (N) and cation (Fe) dopants to the variation of near band gap electronic structure of the co-doped Cu2O are different. Moreover, co-doping reduces the band gap and increases the visible-light absorption of Cu2O. Both band gap reduction and low recombination rate are critical elements for efficient light-to-current conversion in co-doped semiconductor photocatalysts. These findings raise the prospect of using co-doped Cu2O with specifically engineered electronic properties in a variety of solar applications.

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Bahadur, Ali, Tehseen Ali Anjum, Mah Roosh, Shahid Iqbal, Hamad Alrbyawi, Muhammad Abdul Qayyum, Zaheer Ahmad, et al. "Magnetic, Electronic, and Optical Studies of Gd-Doped WO3: A First Principle Study." Molecules 27, no. 20 (October 17, 2022): 6976. http://dx.doi.org/10.3390/molecules27206976.

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Tungsten trioxide (WO3) is mainly studied as an electrochromic material and received attention due to N-type oxide-based semiconductors. The magnetic, structural, and optical behavior of pristine WO3 and gadolinium (Gd)-doped WO3 are being investigated using density functional theory. For exchange-correlation potential energy, generalized gradient approximation (GGA+U) is used in our calculations, where U is the Hubbard potential. The estimated bandgap of pure WO3 is 2.5 eV. After the doping of Gd, some states cross the Fermi level, and WO3 acts as a degenerate semiconductor with a 2 eV bandgap. Spin-polarized calculations show that the system is antiferromagnetic in its ground state. The WO3 material is a semiconductor, as there is a bandgap of 2.5 eV between the valence and conduction bands. The Gd-doped WO3’s band structure shows few states across the Fermi level, which means that the material is metal or semimetal. After the doping of Gd, WO3 becomes the degenerate semiconductor with a bandgap of 2 eV. The energy difference between ferromagnetic (FM) and antiferromagnetic (AFM) configurations is negative, so the Gd-doped WO3 system is AFM. The pure WO3 is nonmagnetic, where the magnetic moment in the system after doping Gd is 9.5599575 μB.

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Spitler, Mark. "Impedance Analysis of Semiconductor Electrodes Biased in the Accumulation Regime for Fuels Evolution." ECS Meeting Abstracts MA2023-01, no. 50 (August 28, 2023): 2570. http://dx.doi.org/10.1149/ma2023-01502570mtgabs.

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This work explores the theory and experimental use of impedance analyses of semiconductor electrodes in the accumulation regime of semiconductor electrodes under bias. It contrasts with the established practice of measuring capacitance of the semiconductor-electrolyte biased in the depletion region to obtain semiconductor doping densities and flatband potentials (Ufb). The goal is to establish Ufb and the solution Helmholtz capacitance for an electrode in the working bias region where research is done on semiconductor electrodes for CO2 reduction and H2 evolution. The technique of measuring the capacitance of semiconductor electrodes when polarized in the depletion region was introduced by DeWald1 and is based upon the work of Garrett and Brattain2 where mathematical expressions were derived for the electric field of a semiconductor space charge region. A significant assumption in that work was that a Boltzmann expression could be used to determine the population of the majority charge carriers in the bands created through ionization of dopant. Research in this area is extensive and has been summarized.3 However, for degenerate semiconductors or for bias potentials of the semiconductor where the fermi level at the electrode surface equals the energy of the band edges, a full fermi function must be employed to describe population statistics in the solid. This is the condition commonly found in systems for fuels production at semiconductor electrodes. The solid state physics theory for this situation is known4 and describes the electric field in a semiconductor space charge region. However, it was put aside during the development of impedance evaluations in semiconductor electrochemistry because its mathematical complexity was too tedious to evaluate at that time. Only limits and simplifications were explored.5 With modern computational software, this theory has become straightforward to calculate and it becomes possible to apply it to experimental systems in a description of behavior over the entire range of doping and polarization. The nature of this full theoretical description will be discussed and illustrated through experimental measurements of Si and InP semiconductor electrodes. References: DeWald, J.F., J. Phys. Chem. Sol., 14, 1960, 155-161. Garrett, C.G.B. and Brattain, W.H., Phys. Rev., 99, 1955, 376-387. Memming, R., Semiconductor Electrochemistry, Second Edition, Wiley-VCH,, Weinheim, Germany, 2015. Seiwatz, R. and Green, M., J. Appl. Phys., 29, 1958, 1034-1040. Many, A., Goldstein, Y., and Grover, N.B., Semiconductor Surfaces, North-Holland Publishing, New York, 1971.

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Fouckhardt, Henning, Johannes Richter, Christoph Doering, and Johannes Strassner. "In Situ and Real-Time Monitoring of Doping Levels by Reflectance Anisotropy Spectroscopy (RAS) during Molecular Beam Epitaxial (MBE) Growth of III/V Semiconductors." Advances in Materials Science and Engineering 2023 (December 13, 2023): 1–12. http://dx.doi.org/10.1155/2023/1319081.

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Reflectance anisotropy/difference spectroscopy (RAS/RDS) had been developed for monitoring epitaxial semiconductor growth, especially for the metal-organic chemical vapor deposition (MOCVD) of III/V semiconductors. But RAS is also well suited for the control of III/V growth with molecular beam epitaxy (MBE). Although the work on RAS has already started at least three decades ago, the potential of this in situ and real-time monitoring technique, especially for doping control, is not well known yet. Experimental results are given here on the identification of doping types and concentration during MBE growth, exemplarily for GaAs and AlGaAs. Especially, the dependence of the majority charge carrier concentration (i.e., the doping concentration) on the RAS signal difference between the nondoping and doping cases is addressed here.

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Liu, Anmin, Mengfan Gao, Yan Ma, Xuefeng Ren, Liguo Gao, Yanqiang Li, and Tingli Ma. "Theoretical study of the influence of doped oxygen group elements on the properties of organic semiconductors." Nanoscale Advances 3, no. 11 (2021): 3100–3106. http://dx.doi.org/10.1039/d0na01026j.

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Doping oxygen group elements on the properties of organic semiconductor were studied by DFT; the doping of multi-element Te has high stability and mobility; provide guidance for preparing high-performance organic semiconductor materials.

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Cheng, Ruoran, Chunli Zhang, Weiqiu Chen, and Jiashi Yang. "Temperature Effects on Mobile Charges in Extension of Composite Fibers of Piezoelectric Dielectrics and Non-Piezoelectric Semiconductors." International Journal of Applied Mechanics 11, no. 09 (November 2019): 1950088. http://dx.doi.org/10.1142/s1758825119500881.

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We study the redistribution of mobile charge carriers in a composite fiber of piezoelectric dielectrics and non-piezoelectric semiconductors in extensional deformation under a uniform temperature change. The macroscopic theory of piezoelectricity and the drift-diffusion theory of semiconductor are used, coupled by doping and mobile charges. A one-dimensional model for extension is developed. Through a theoretical analysis, it is shown that under a temperature change the mobile charges in the semiconductor redistribute themselves under the polarization and electric field produced through thermoelastic, pyroelectric and piezoelectric effects. The results suggest the possibility of using composite structures for thermally manipulating mobile charges in semiconductors and have potential applications in piezotronics.

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Gupta, Gaurav, Bijoy Rajasekharan, and Raymond J. E. Hueting. "Electrostatic Doping in Semiconductor Devices." IEEE Transactions on Electron Devices 64, no. 8 (August 2017): 3044–55. http://dx.doi.org/10.1109/ted.2017.2712761.

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MIURA, N., Y. H. MATSUDA, and T. IKAIDA. "MEGAGAUSS CYCLOTRON RESONANCE IN SEMICONDUCTOR NANOSTRUCTURES AND DILUTED MAGNETIC SEMICONDUCTORS." International Journal of Modern Physics B 16, no. 20n22 (August 30, 2002): 3399–404. http://dx.doi.org/10.1142/s0217979202014565.

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We report the latest results of cyclotron resonance experiments on semiconductor nanostructures and diluted magnetic semiconductors (DMS) in very high magnetic fields up to 600 T produced by magnetic flux compression and the single turn coiled technique. Many new features were observed in the very high field range, such as characteristic behavior of low dimensional electrons, carrier dynamics or electron-electron interaction effects in quantum wells and quantum dot samples. In PbSe/PdEuTe quantum dots, which were regularly arranged to form an fcc superlattice, we observed an absorption peak with a splitting and a wavelength dependence of the absorption intensity. In DMS, such as CdMnTe and InMnAs, change of the carrier effective mass with Mn doping was studied in detail. We found anomalous mass increase with doping of magnetic ions. The amount of the observed mass increase cannot be explained by the k·p theory and suggests the importance of d-s or d-p hybridization.

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Chen, Ping, Hua Zhang, Pingying Tang, and Binbin Li. "A hybrid density functional design of intermediate band semiconductor for photovoltaic application based on group IV elements (Si, Ge, Sn, and Pb)-doped CdIn₂S₄." Journal of Applied Physics 131, no. 13 (April 7, 2022): 135702. http://dx.doi.org/10.1063/5.0082631.

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The CdIn2S4 semiconductor is considered a potential host for the implementation of intermediate band solar cells due to its ideal bandgap value and excellent photoelectric property. In this paper, the electronic structures of group IV elements (Si, Ge, Sn, and Pb)-doped CdIn2S4 have been investigated by using hybrid density functional calculations. In the case of Ge, Sn, and Pb doping, an isolated and partially occupied intermediated band with delocalized characteristics could be created in the bandgap of the host. The results of the projected density of states reveal that the intermediated band is derived from the hybridization between the S-3 p and dopant- ns states. Thanks to the assistance of the impurity band, the optical absorption ability of the intermediate band semiconductor is greatly enhanced. Based on the detailed balance theory, the theoretical efficiencies of intermediate band solar cells made by Ge- and Pb-doped CdIn2S4 are estimated to be 45.0% and 49.2%, respectively, which are superior to the Shockley and Queisser limit (40.7%) of a single junction photovoltaic device. Moreover, the experimental synthesis of these impurity semiconductors is relatively feasible because substitutional doping at the octahedral position is energetically favorable. These findings would be helpful to the development of a high-efficiency intermediate band solar cell.

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Gack, Nicolas, Gleb Iankevich, Cahit Benel, Robert Kruk, Di Wang, Horst Hahn, and Thomas Reisinger. "Magnetotransport Properties of Ferromagnetic Nanoparticles in a Semiconductor Matrix Studied by Precise Size-Selective Cluster Ion Beam Deposition." Nanomaterials 10, no. 11 (November 3, 2020): 2192. http://dx.doi.org/10.3390/nano10112192.

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The combination of magnetic and semiconducting properties in one material system has great potential for integration of emerging spintronics with conventional semiconductor technology. One standard route for the synthesis of magnetic semiconductors is doping of semiconductors with magnetic atoms. In many semiconductor–magnetic–dopant systems, the magnetic atoms form precipitates within the semiconducting matrix. An alternative and controlled way to realize such nanocomposite materials is the assembly by co-deposition of size-selected cluster ions and a semiconductor. Here we follow the latter approach to demonstrate that this fabrication route can be used to independently study the influence of cluster concentration and cluster size on magneto-transport properties. In this case we study Fe clusters composed of approximately 500 or 1000 atoms soft-landed into a thermally evaporated amorphous Ge matrix. The analysis of field and temperature dependent transport shows that tunneling processes affected by Coulomb blockade dominate at low temperatures. The nanocomposites show saturating tunneling magnetoresistance, additionally superimposed by at least one other effect not saturating upon the maximum applied field of 6 T. The nanocomposites’ resistivity and the observed tunneling magnetoresistance depend exponentially on the average distance between cluster surfaces. On the contrary, there is no notable influence of the cluster size on the tunneling magnetoresistance.

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Lee, Dongwook. "Enhancement of thermoelectric power factor by modulation doping of bulk polycrystalline SnS / thin film PEDOT:PSS bilayer." Korean Journal of Metals and Materials 60, no. 7 (July 5, 2022): 531–36. http://dx.doi.org/10.3365/kjmm.2022.60.7.531.

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Modulation doping occurs in a heterojunction where a charge carrier-rich material transfers charge to a carrier-deficient material. The modulation-doped material is intentionally selected to have higher charge carrier mobility than the modulation dopant material, so that the overall electrical conductivity can be boosted. Although this modulation doping strategy has proven effective in enhancing power factor in thermoelectrics, selection criteria for such semiconductor couples have not been explicitly clarified, resulting in only a few discovered semiconductor couples available for modulation doping-driven thermoelectric systems [1-4]. Here, we (i) report an electronic band structure-based guideline to actualize modulation doping, (ii) reveal that hole-rich PEDOT:PSS can modulation dope otherwise undoped tin monosulfide (SnS) in their bilayered structure, (iii) prove that modulation doping is responsible for thermoelectric power factor enhancement by comparing computational and experimental Seebeck coefficient and electrical conductivity values. The optimized PEDOT:PSS thin film / SnS pellet bilayered structure had a 134.7 fold improvement in electrical conductivity and a 93.6 fold power factor enhancement over those of undoped SnS, with only a ~ 20 % decrease in Seebeck coefficient. The modulation doping effect can result in further power factor improvement when SnS becomes a nanoscale thin film or nanoparticles in the future.

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Ling, Tao, Xiaoping Zou, Jin Cheng, Ying Yang, Haiyan Ren, and Dan Chen. "Modulating Surface Morphology Related to Crystallization Speed of Perovskite Grain and Semiconductor Properties of Optical Absorber Layer under Controlled Doping of Potassium Ions for Solar Cells." Materials 11, no. 9 (September 4, 2018): 1605. http://dx.doi.org/10.3390/ma11091605.

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Perovskite thin films with excellent optical semiconductor and crystallization properties and superior surface morphology are normally considered to be vital to perovskite solar cells (PSCs). In this paper, we systematically survey the process of modulating surface morphology and optical semiconductor and crystallization properties of methylammonium lead iodide film by controlling doping of K+ for PSC prepared in air and propose the mechanism of large K+-doped perovskite grain formation related to crystallization speed. The increase in the crystallization speed leads to the production of large grains without localized-solvent-vapor (LSV) pores via moderate doping of K+, and the exorbitant crystallization speed induces super large grains with LSV pores via excessive doping of K+. Furthermore, the semiconductor properties (absorption band edge wavelength, PL emission peak wavelength, energy band gap) of perovskite film can be significantly tuned by controlled doping of K+. The investigation of the detailed process of modulating surface morphology and semiconductor properties of perovskite thin film by controlled doping of K+ may provide guidance and pave the way for superior component design of absorption materials for cost-efficient PSCs.

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Ahmad, Habib, Zachary Engel, Christopher M. Matthews, Sangho Lee, and W. Alan Doolittle. "Realization of homojunction PN AlN diodes." Journal of Applied Physics 131, no. 17 (May 7, 2022): 175701. http://dx.doi.org/10.1063/5.0086314.

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Aluminum nitride (AlN) is an insulator that has shown little promise to be converted to a semiconductor via impurity doping. Some of the historic challenges for successfully doping AlN include a reconfigurable defect formation known as a DX center and subsequent compensation that causes an increase in dopant activation energy resulting in very few carriers of electricity, electrons, or holes, rendering doping inefficient. Using crystal synthesis methods that generate less compensating impurities and less lattice expansion, thus impeding the reconfiguration of dopants, and using new dopants, we demonstrate: (a) well behaved bulk semiconducting functionality in AlN, the largest direct bandgap semiconductor known with (b) substantial bulk p-type conduction (holes = 3.1 × 1018 cm−3, as recently reported in our prior work), (c) dramatic improvement in n-type bulk conduction (electrons = 6 × 1018 cm−3, nearly 6000 times the prior state-of-the-art), and (d) a PN AlN diode with a nearly ideal turn-on voltage of ∼6 V for a 6.1 eV bandgap semiconductor. A wide variety of AlN-based applications are enabled that will impact deep ultraviolet light-based viral and bacterial sterilization, polymer curing, lithography, laser machining, high-temperature, high-voltage, and high-power electronics.

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Tan, Changlong, Dianshuang Xu, Kun Zhang, Xiaohua Tian, and Wei Cai. "Electronic and Magnetic Properties of Rare-Earth Metals Doped ZnO Monolayer." Journal of Nanomaterials 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/329570.

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The structural, electronic, and magnetic properties of rare-earth metals doped ZnO monolayer have been investigated using the first-principles calculations. The induced spin polarization is confirmed for Ce, Eu, Gd, and Dy dopings while the induced spin polarization is negligible for Y doping. The localizedfstates of rare-earth atoms respond to the introduction of a magnetic moment. ZnO monolayer undergoes transition from semiconductor to metal in the presence of Y, Ce, Gd, and Dy doping. More interestingly, Eu doped ZnO monolayer exhibits half-metallic behavior. Our result demonstrates that the RE-doping is an efficient route to modify the magnetic and electronic properties in ZnO monolayer.

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Shim, Moonsub, Congjun Wang, David J. Norris, and Philippe Guyot-Sionnest. "Doping and Charging in Colloidal Semiconductor Nanocrystals." MRS Bulletin 26, no. 12 (December 2001): 1005–8. http://dx.doi.org/10.1557/mrs2001.257.

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Modern semiconductor technology has been enabled by the ability to control the number of carriers (electrons and holes) that are available in the semiconductor crystal. This control has been achieved primarily with two methods: doping, which entails the introduction of impurity atoms that contribute additional carriers into the crystal lattice; and charging, which involves the use of applied electric fields to manipulate carrier densities near an interface or junction. By controlling the carriers with these methods, the electrical properties of the semiconductor can be precisely tailored for a particular application. Accordingly, doping and charging play a major role in most modern semiconductor devices.

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Awsiuk, Kamil, Paweł Dąbczyński, Mateusz M. Marzec, Jakub Rysz, Ellen Moons, and Andrzej Budkowski. "Electrically Switchable Film Structure of Conjugated Polymer Composites." Materials 15, no. 6 (March 17, 2022): 2219. http://dx.doi.org/10.3390/ma15062219.

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Domains rich in different blend components phase-separate during deposition, creating a film morphology that determines the performance of active layers in organic electronics. However, morphological control either relies on additional fabrication steps or is limited to a small region where an external interaction is applied. Here, we show that different semiconductor-insulator polymer composites can be rapidly dip-coated with the film structure electrically switched between distinct morphologies during deposition guided by the meniscus formed between the stationary barrier and horizontally drawn solid substrate. Reversible and repeatable changes between the morphologies used in devices, e.g., lateral morphologies and stratified layers of semiconductors and insulators, or between phase-inverted droplet-like structures are manifested only for one polarity of the voltage applied across the meniscus as a rectangular pulse. This phenomenon points to a novel mechanism, related to voltage-induced doping and the doping-dependent solubility of the conjugated polymer, equivalent to an increased semiconductor content that controls the composite morphologies. This is effective only for the positively polarized substrate rather than the barrier, as the former entrains the nearby lower part of the coating solution that forms the final composite film. The mechanism, applied to the pristine semiconductor solution, results in an increased semiconductor deposition and 40-times higher film conductance.

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GRAHAM, RION, and DONG YU. "SCANNING PHOTOCURRENT MICROSCOPY IN SEMICONDUCTOR NANOSTRUCTURES." Modern Physics Letters B 27, no. 25 (September 23, 2013): 1330018. http://dx.doi.org/10.1142/s0217984913300184.

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Scanning photocurrent microscopy (SPCM) is a powerful experimental tool used to investigate spatially resolved optoelectronic properties of semiconductors and their nanostructures. Raster-scanned laser excitation generates a position-dependent photocurrent map from which carrier diffusion length, electric field distribution, doping concentration and more can be explored. In this review, we will briefly discuss the history of the technique, the theory behind locally injected carrier transport in semiconductors, the SPCM experimental setup, and recent applications of SPCM in semiconductor nanostructures. Particularly, we have shown that the minority carrier diffusion length can also be obtained by SPCM in two-dimensional semiconductors and that the local excitation can result in an internal electric field because of the difference in electron and hole mobilities.

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Garba, I. I., R. Nasiru, Y. M. Abubakar, and U. Shehu. "Modeling and Bulk Characterization of 4HSIC Radiation Detector in Sentaurus TCAD Simulation Environment." Dutse Journal of Pure and Applied Sciences 10, no. 1c (April 24, 2024): 201–10. http://dx.doi.org/10.4314/dujopas.v10i1c.19.

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This paper gives an insight into the need for radiation detection and the most commonly flexible and efficient radiation detector. It also examines bulk characteristics of 4H-SiC semiconductor radiation detector with Ni and Ti as metals for the contact. Bulk characterization of the device, including: doping concentration, electrons and holes behaviors, space charge and current densities were carried out. The modeling is conducted using Sentaurus Technology Computer Aided Design (TCAD) to examine charge transport in bulk 4HSiC material. Data obtained were further analyzed through Sentaurus visual, sentaurus Techplot and Excel to clearly determine the characteristics of the device. It is observed that when the semiconductor and metal are in contact, the Fermi-level is established where the doping concentration varied with either magnitude of the doping concentration or nature of the dopant. Similarly, Schottky and ohmic contacts and temperature effect were observed from the device characteristics which demonstrate that, the detector can withstand a temperature from the range of 100K to 700K in no fluctuating state.

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Norman, Joseph Wayne, and Sam-Shajing Sun. "A Thermoelectric Polymer Field-Effect Transistor via Iodine-Doped P3HT." Micromachines 15, no. 2 (January 24, 2024): 172. http://dx.doi.org/10.3390/mi15020172.

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Doping can alter certain electronics, including the thermoelectric properties of an organic semiconductor. These alterations may enable viable tunable devices that could be useful in temperature sensing for autonomous controls. Here, we demonstrate a dual-modulation organic field-effect transistor (OFET) where temperature can modulate the current-voltage characteristics of the OFET and gate voltage can modulate the thermoelectric properties of the active layer in the same device. Specifically, Poly(3-hexylthiophene-2,5-diyl) (P3HT) was utilized as the host p-type semiconducting polymer, and iodine was utilized as the thermoelectric minority dopant. The finished devices were characterized with a semiconductor analyzer system with temperature controlled using two thermoelectric cooling plates. The FETs with iodine doping levels in the range of 0.25% to 0.5% mole ratio with respect to the P3HT exhibit the greatest on/off ratios. This study also observed that P3HT thin film samples with an intermediate iodine doping concentration of 0.25% mole ratio exhibit an optimal thermoelectric power factor (PF).

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Zolfaghari, Mahmoud, and Mahshid Chireh. "Effect of Mn Dopant on Lattice Parameters and Band Gap Energy of Semiconductor ZnO Nanoparticles." Advanced Materials Research 829 (November 2013): 784–89. http://dx.doi.org/10.4028/www.scientific.net/amr.829.784.

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ZnO belongs to the II-VI semiconductor group with a direct band-gap of 3.2-3.37 eV in 300K and a high exciton binding energy of 60 meV. It has good transparency, high electron mobility, wide, and strong room-temperature luminescence. These properties have many applications in a wide area of emerging applications. Doping ZnO with the transition metals gives it magnetic property at room temperature hence making it multifunctional material, i.e. coexistence of magnetic, semiconducting and optical properties. The samples can be synthesized in the bulk, thin film, and nanoforms which show a wide range of ferromagnetism properties. Ferromagnetic semiconductors are important materials for spintronic and nonvolatile memory storage applications. Doping of transition metal elements into ZnO offers a feasible means of tailoring the band gap to use it as light emitters and UV detector. As there are controversial on the energy gap value due to change of lattice parameters we have synthesized Mn-doped ZnO nanoparticles by co-precipitation method with different concentrations to study the effect of lattice parameters changes on gap energy. The doped samples were studied by XRD, SEM, FT-IR., and UV-Vis. The XRD patterns confirm doping of Mn into ZnO structure. As Mn concentrations increases the peak due to of Mn impurity in FT-IR spectra becomes more pronounces hence confirming concentrations variation. We find from UV-Vis spectra that the gap energy due to doping concentration increases due to the Goldschmidt-Pauling rule this increase depends on dopant concentrations and increases as impurity amount increases.

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Meng, Lingju, and Xihua Wang. "Doping Colloidal Quantum Dot Materials and Devices for Photovoltaics." Energies 15, no. 7 (March 27, 2022): 2458. http://dx.doi.org/10.3390/en15072458.

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Colloidal semiconductor nanocrystals have generated tremendous interest because of their solution processability and robust tunability. Among such nanocrystals, the colloidal quantum dot (CQD) draws the most attention for its well-known quantum size effects. In the last decade, applications of CQDs have been booming in electronics and optoelectronics, especially in photovoltaics. Electronically doped semiconductors are critical in the fabrication of solar cells, because carefully designed band structures are able to promote efficient charge extraction. Unlike conventional semiconductors, diffusion and ion implantation technologies are not suitable for doping CQDs. Therefore, researchers have creatively developed alternative doping methods for CQD materials and devices. In order to provide a state-of-the-art summary and comprehensive understanding to this research community, we focused on various doping techniques and their applications for photovoltaics and demystify them from different perspectives. By analyzing two classes of CQDs, lead chalcogenide CQDs and perovskite CQDs, we compared different working scenarios of each technique, summarized the development in this field, and raised our own future perspectives.

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Guruswamy, B., V. Ravindrachary, C. Shruthi, and M. Mylarappa. "Effect of SnO₂ Nanoparticle Doping on Structural, Morphological and Thermal Properties of PVA-PVP Polymer Blend." Materials Science Forum 962 (July 2019): 82–88. http://dx.doi.org/10.4028/www.scientific.net/msf.962.82.

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The n-type semiconductor SnO2 nanoparticles were synthesised using standard route and the effect of this nanoparticle doping on structural, morphological and thermal properties of PVA-PVP polymer blend has been investigated. Pure and PVA-PVP/SnO2 Nanocomposite films were prepared using solution casting technique. The powder X-ray diffraction result shows that the crystalline nature of the blend increases with doping level. FESEM study shows that the surface morphology of the polymer nanocomposite varies with doping level. AFM study reveals that in the nanocomposite films, the average roughness changes with dopant concentration. The DSC studies on the samples were performed from 40°C to 400°C under nitrogen atmosphere and it shows that the thermal properties of the blend changes with doping concentration.

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Bai, Jin Rui, and Rui Xiang Hou. "The Study of Surface Morphology and Roughness of Silicon Wafers Treated by Plasma." Materials Science Forum 980 (March 2020): 88–96. http://dx.doi.org/10.4028/www.scientific.net/msf.980.88.

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Plasma is generally used for the doping of semiconductors. During plasma doping process, plasma interacts with the surface of semiconductor. As a result, defects are induced in the surface region. In this work, the surface morphology and roughness of silicon wafer caused by plasma treatment is studied by use of atom force microscope (AFM). It is found that, during the plasma process, each of the processing time of plasma, location of silicon wafer in plasma and the way of placement of silicon wafer has an influence on the surface morphology and roughness and the reason is discussed. The interaction between plasma and the surface of silicon wafer is qualitatively discussed.

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Gnatyuk, Volodymyr A., Sergiy N. Levytskyi, Oleksandr I. Vlasenko, and Toru Aoki. "Laser-Induced Doping of CdTe Crystals in Different Environments." Advanced Materials Research 222 (April 2011): 32–35. http://dx.doi.org/10.4028/www.scientific.net/amr.222.32.

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Different procedures of laser-induced doping of the surface region of semi-insulating CdTe semiconductor are discussed. CdTe crystals pre-coated with an In dopant film were subjected to irradiation with nanosecond laser pulses in different environments (vacuum, gas or water). The dopant self-compensation phenomenon was overcome under laser action and In impurity with high concentration was introduced in a thin surface layer of CdTe. In the case of a thick (300-400 nm) In dopant film, laser-induced shock wave action has been considered as the mechanism of solid-phase doping. Formed In/CdTe/Au diode structures showed high rectification depending on the fabrication procedure. Diodes with low leakage current were sensitive to high energy radiation.

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Chen, Xingyu. "Methods for Improving the Mobility of Semiconductor Carriers." Highlights in Science, Engineering and Technology 84 (February 27, 2024): 81–85. http://dx.doi.org/10.54097/pkn24993.

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Semiconductor is the core of the information technology industry and a leading industry supporting economic and social development. Its products are mainly used in various fields such as computers, digital electronics, electrical, transportation, medical, aerospace, and so on. In recent years, the semiconductor application field has been continuously expanding with technological progress, and emerging fields such as 5G, artificial intelligence, intelligent driving, robotics, and drones have flourished, bringing new opportunities to the semiconductor industry. The main properties of semiconductors include conductivity, internal field, carrier concentration, and mobility. These properties are influenced by factors such as the preparation, processing technology, and device design of semiconductor materials. Among them, mobility is an important physical quantity that marks the speed of semiconductor carrier movement under the action of an electric field, and its size directly affects the working frequency and speed of semiconductor devices and circuits. For bipolar transistors, high carrier mobility can shorten the time for carriers to cross the base region, increase the characteristic frequency, and effectively improve the frequency, speed, and noise performance of the device. For field-effect transistors, improving carrier mobility is of greater significance. Therefore, this article summarizes different methods for improving semiconductor carrier mobility, including reducing impurities and defects, controlling lattice structure, adjusting doping element concentration, and intermolecular stacking. This page also describes the areas in which semiconductors with high carrier mobility are used, to serve as a reference for future semiconductor research.

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Journal articles on the topic 'Semiconductor doping'

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