Tesi sul tema "Polycrystalline semiconductors"
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Burg, Tristan Kevin Materials Science & Engineering Faculty of Science UNSW. "Semiconducting properties of polycrystalline titanium dioxide". Publisher:University of New South Wales. Materials Science & Engineering, 2008. http://handle.unsw.edu.au/1959.4/41262.
Testo completoKarbasi, Hossein. "Deep level transient spectroscopy of heteroepitaxial polycrystalline diamond and aluminum nitride /". free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9901245.
Testo completoJudson, Elizabeth Ann. "An analysis of preferred orientation in YBa₂ Cu₃ O₇ ₋ ₓ superconducting films deposited by CVD on single and polycrystalline substracts". Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/8562.
Testo completoGolego, Nickolay. "Thin-film polycrystalline titanium-oxygen semiconductors prepared by spray pyrolysis". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ33300.pdf.
Testo completoArmstrong, Jeffrey Lee. "Reaction of carbonyl-and nitrogen-containing molecules on Si(100) and fluxless solder re-flow on polycrystalline Cu surfaces /". Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
Testo completoMurphy, Robert Clayton. "Effects of material inhomogeneity on the terminal characteristics of polycrystalline silicon solar cells /". Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
Testo completoSong, Dengyuan Centre for Photovoltaic Engineering UNSW. "Zinc oxide TCOs (Transparent Conductive Oxides) and polycrystalline silicon thin-films for photovoltaic applications". Awarded by:University of New South Wales. Centre for Photovoltaic Engineering, 2005. http://handle.unsw.edu.au/1959.4/29371.
Testo completoAl-Ahmadi, Ahmad Aziz. "Fabrication and characterization of ZnO film by spray pyrolysis and ZnO polycrystalline sintered pellets doped with rear earth ions". Ohio : Ohio University, 2003. http://www.ohiolink.edu/etd/view.cgi?ohiou1175017625.
Testo completoKhadilkar, Unmesh. "Modeling and Characterization of Polycrystalline Mercuric Iodide Radiation Detectors". [Tampa, Fla. : s.n.], 2003. http://purl.fcla.edu/fcla/etd/SFE0000088.
Testo completoAlbin, David Scott. "Fabrication and structural, optical, and electrical characterization of multisource evaporated copper-gallium-selenide polycrystalline thin films". Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184745.
Testo completoShi, Lei Photovoltaics & Renewable Energy Engineering Faculty of Engineering UNSW. "Contact resistance study on polycrystalline silicon thin-film solar cells on glass". Publisher:University of New South Wales. Photovoltaics & Renewable Energy Engineering, 2008. http://handle.unsw.edu.au/1959.4/41425.
Testo completoBaier, Robert [Verfasser]. "Electronic grain boundary properties in polycrystalline Cu(In,Ga)Se2 semiconductors for thin film solar cells / Robert Baier". Berlin : Freie Universität Berlin, 2012. http://d-nb.info/1027815618/34.
Testo completoMackay, Ian. "Thin film electroluminescence /". Online version of thesis, 1989. http://hdl.handle.net/1850/10551.
Testo completoHo, Kang Jin. "Studies on Amorphous Silicon Thin Films Doped with Aluminium". Thesis, Indian Institute of Science, 1995. https://etd.iisc.ac.in/handle/2005/157.
Testo completoHo, Kang Jin. "Studies on Amorphous Silicon Thin Films Doped with Aluminium". Thesis, Indian Institute of Science, 1995. http://hdl.handle.net/2005/157.
Testo completoLee, Shih-Chung. "Physically-based modelling of polycrystalline semiconductor devices". Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394408.
Testo completoGarcia, Victoria. "Effect of dislocation density on residual stress in polycrystalline silicon wafers". Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22621.
Testo completoSt, Omer Ingrid L. J. "The pressure response of synthetic polycrystalline diamond f ilms /". free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9737861.
Testo completoЗнаменщиков, Ярослав Володимирович, Ярослав Владимирович Знаменщиков, Yaroslav Volodymyrovych Znamenshchykov, Володимир Володимирович Косяк, Владимир Владимирович Косяк, Volodymyr Volodymyrovych Kosiak, Анатолій Сергійович Опанасюк, Анатолий Сергеевич Опанасюк, Anatolii Serhiiovych Opanasiuk e P. M. Fochuk. "Effect of Laser Annealing on the Properties of the Surface of Polycrystalline CdZnTe Thick Film". Thesis, Sumy State University, 2015. http://essuir.sumdu.edu.ua/handle/123456789/42798.
Testo completoJAYASEELAN, VIDHYA SAGAR. "STUDY OF POLYCRYSTALLINE DIAMOND THIN FILMS GROWN IN A CUSTOM BUILT ECR PE-CVD SYSTEM". University of Cincinnati / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ucin975513169.
Testo completoGolestanian, Hassan. "Chemical vapor deposited boron doped polycrystalline diamond thin film growth on silicon and sapphire growth, doping, metallization, and characterization /". free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9841292.
Testo completoZhang, Fengguo. "Determination of the stress field in polycrystalline materials by Laue microdiffraction". Thesis, Paris, ENSAM, 2015. http://www.theses.fr/2015ENAM0020/document.
Testo completoLaue microdiffraction is a powerful technique to characterize the intragranular elastic strain field at the scale of micrometer. Although a standard procedure extracting elastic strain and crystal orientation from Laue image has been well-established, it can suffer from two sources of uncertainties: the determination of peaks' positions and the sensitivity to calibration parameters. In light of the high accuracy of digital image correlation (DIC), we developed the so-called Laue-DIC method which used the peaks' displacements measured by DIC instead of peaks' positions to determine the elastic strain increment and rotation between two mechanical configurations. This method has been proved more efficient than the standard procedure in terms of stress profiles of bended beam. We also developed the enhanced version of Laue-DIC. By using the term “enhanced”, we mean that we attempt to obtain both lattice matrices and calibration parameters of two configurations rather than solely the elastic strain increment and rotation from peaks' displacements.Aside from the formulation of Laue-DIC, we also developed a procedure of statistically estimating the errors of elastic strain/stress resulted from DIC errors and calibration accuracy. We have first validated a classical noise model, Poissonian-Gaussian model, from diffraction images acquired at synchrotron radiation facility. With the noise model, we could statistically estimate the DIC errors by synthesizing artificial spots. The estimated DIC errors were further transmitted into the errors of Laue-DIC through statistical tests
Turcu, Mircea Cassian. "Defect energies, band alignments, and charge carrier recombination in polycrystalline Cu(In,Ga)(Se,S)2 alloys". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1086247686828-95497.
Testo completoTurcu, Mircea Cassian. "Defect energies, band alignments, and charge carrier recombination in polycrystalline Cu(In,Ga)(Se,S)2 alloys". Doctoral thesis, Technische Universität Dresden, 2003. https://tud.qucosa.de/id/qucosa%3A24342.
Testo completoMih, Thomas Attia. "A novel low-temperature growth method of silicon structures and application in flash memory". Thesis, De Montfort University, 2011. http://hdl.handle.net/2086/5183.
Testo completoPavlov, Marko. "Modélisation numérique du couplage thermique-photoélectrique pour des modules photovoltaïques sous faible concentration". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS361/document.
Testo completoThe poor utilisation of the inter-row irradiation limits the production of photovoltaic (PV) modules. The "Aleph" project explores the potential of adding inter-row planar reflectors to increase the system yield, and defines clear rules for optimal settings of such systems in a given location and under a given climate. This work presents a multiphysics model of the system, numerical simulations of its behaviour, and the comparison with experimental data. Two PV module technologies are tested: amorphous silicon (a-Si) and polycrystalline silicon (p-Si). The experimental data show significant gains in produced energy brought by the reflectors. The gains are higher for a-Si modules compared to p-Si. The modelling work combines a Monte-Carlo ray-tracing optical model (EDStaR), a photo-electric model (SPICE), and an empirical thermal model. The complete model is calibrated with measurements using an evolutionary algorithm. Once calibrated, the model demonstrates good performance in predicting the module power output as a function of atmospheric and irradiance data
Said-Bacar, Zabardjade. "Elaboration et caractérisations de silicium polycristallin par cristallisation en phase liquide du silicium amorphe". Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00680303.
Testo completo"Phosphorous diffusion and hydrogen passivation of polycrystalline silicon for photovoltaic cells". Thesis, 2012. http://hdl.handle.net/10210/5415.
Testo completoTechniques for the fabrication of polycrystalline silicon solar cells have advanced in recent years with efficiencies exceeding 17%. The major advantage of polycrystalline silicon is its low cost relative to single-crystalline silicon. The disadvantage is the significantly smaller minoritycarrier bulk diffusion length and inhomogeneous nature of the material. These two drawbacks are due to the presence of grain boundaries as well as high concentrations of dislocations and other physical and chemical defects. In this study the experimental conditions were determined to fabricate solar cells on polycrystalline silicon substrates. The controlled diffusion of phosphorous into silicon and subsequent evaluation of the doped layers (by spreading resistance profiling and chemical staining) were important aspects of this study. From these results the diffusion parameters (i.e. temperature and reaction times) could be optimized in order to improve the solar cell output parameters. Additional material improvement (increase in surface- and bulk minority carrier lifetimes) was demonstrated by the hydrogen passivation of electrically active defects in polycrystalline silicon. However. measurements on hydrogenated silicon samples also indicated that excess passivation can result in surface damage and subsequent reduction in the minority carrier lifetimes. Preliminary solar cells were fabricated on polycrystalline silicon with efficiencies ranging between 0.5 and 6% (total area = 16 cm2).
Langa, Dolly Frans. "Comparison of the structural properties of a-Si:H and CulnSe₂ on glass and flexible substrates". Thesis, 2012. http://hdl.handle.net/10210/4540.
Testo completoThin film solar cells based on polycrystalline indium diselenide (CulnSe₂) and amorphous silicon (a-Si:H) are promising candidates for the efficient conversion of sunlight into useable, cheap electrical energy. However, typical device structures are rather complex and consists of semiconductor/metal contacts as well as complicated p - n and p - i - n heterojunctions. In this study, CulnSe₂ absorber layers with excellent material properties were prepared by the selenization of metallic alloys. The a-Si:H thin films were deposited by radio frequency (RF) glow discharge in vacuum. The polycrystalline and amorphous absorber layers were deposited on glass and flexible substrates. In each case, a systematic study was conducted in which all the relevant processing parameters were varied over a broad range. These studies indicated that the structural features of the substrate significantly influence the structural features of the semiconductor thin films. The flexible substrate (kapton) was characterized by the presence of ridges, which distorted the growth behavior of the films. Deposition of ln/Cu/ln metallic alloys onto Mo coated glass (kapton) resulted in discontinuous metallic alloys, which were characterized by the presence of separated elongated island structures. The structural features of the precursors were maintained in the absorber film after selenization in elemental Se vapor. The morphological features of the CulnSe₂ absorber films were also critically influenced by the reaction temperature And reaction period to Se. The structural features on a-Si:H was significantly influenced by the structural features of the particular substrate used. Atomic force microscopy (AFM) imaging in combination with statistical analysis revealed higher roughness values when the amorphous semiconductor materials were deposited onto kapton, which negatively impacts on the device properties of solar cell devices.
Carpenter, Derrick Todd. "Improvements in the characterization of polycrystalline thin films : microchemistry, microtexture and microstructure /". Diss., 1998. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:9919140.
Testo completoBekker, Willem Johannes. "Structural analysis of polycrystalline CuInSe₂ thin films". Thesis, 2010. http://hdl.handle.net/10210/3525.
Testo completoCuInSe2 (CIS) is considered to be one of the most promising candidates for high efficiency thin film solar cells. The reaction of metallic alloys to a reactive selenium atmosphere (H2Se/Ar or elemental Se vapour) is a promising growth technique to produce CIS thin films of high crystalline quality. However, up to now, the control of the final film quality has been critically influenced by the loss of material and subsequent formation of detrimental binary phases during the high temperature selenization stages. In this study, it is shown that this phenomenon is strongly related to the selenization temperature and, in particular, the ramping procedure followed to the final selenization temperature. Metallic alloys which were selenized in H2Se/Ar at 400°C or slowly heated in 20 minutes to temperatures around 400°C were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) to have nonuniform surface morphologies, highly defected 0.8-2 !lm sized grains and to contain Cuselenide binary phases. Energy dispersive X-ray spectroscopy (EDS) analysis confirmed the generally reported sharp increase in the Cu/In atomic ratio for these classes of samples. In contrast, rapid heating (in 2 minutes) of identical metallic alloys to temperatures above 400°C, resulted in uniform, dense films with low defect density 1 !lm sized grains void of any evidence of secondary phases. X-ray fluorescence (XRF) Kal,2 measurements of metallic alloys at different stages of selenization revealed no evidence of material losses. XRF depth profiles, however, explained this discrepancy by revealing a pronounced segregation of In towards the Mo back contact when the samples were selenized at 400°C, or slowly heated to temperatures around 400°C. This segregation was dramatically reduced in films rapidly heated and selenized at temperatures above 400°C. For the purpose of comparison, metallic alloys were also reacted to elemental Se vapour. The structural features (grain size and preferred orientation) ofthese films differed significantly from those selenized under similar conditions in H2Se/Ar. The results from this study, including photoluminescence (PL) measurements obtained from these films, were used to affect the fabrication of CIS absorbers with excellent material properties and solar cell devices with moderate conversion efficiencies.
Van, der Merwe Johan Petrus. "Elektriese eienskappe van aluminium kontakte op polikristallyne silikon". Thesis, 2012. http://hdl.handle.net/10210/6737.
Testo completoThe efficiency of commercial polycrystalline silicon solar cells is currently 12% and 15% in the case of single crystalline cells. It is possible to lose about half of the open circuit voltage due to inferior contacts on the cell. It is thus clear that inferior contacts can seriously impede the relative low efficiency and care should be taken to make good ohmic contacts. Experiments were done to evaluate the influence of several factors on the quality and stability of the contacts. 1 C2•cm p-type polycrystalline silicon and 3 52.cm n-type single crystalline silicon were primarily used for these experiments. Results of molybdenum contacts on n-type silicon are also presented and the problems with silver epoxy contacts are discussed. It was found that aluminium contacts on p-type polycrystaline silicon improve with temperature and time, while those on single crystaline n-type degrade with temperature and time. These changes are already present at room temperature and are attributed to solid state diffusion of the aluminium into the silicon. This results in a p + layer. In the case of contacts on p-type, the behaviour is that of a Schottky diode. After the solid state diffusion, it becomes possible for the charges to quantum mechanically tunnel through the p+ layer. This results in an improvement of the contact. The contacts on n-type however, are ohmic just after evaporation. Similar to the p-material, the p+ layer causes a p+-n-junction with the depletion layer primarily in the n-type material. This causes a degradation in the contact quality. It is possible to achieve good quality contacts on polycrystaline p-type material, by annealing the contacts above 500°C for one minute. These contacts however, are non-ideal. SEM photographs show that the silicon surface is crated by pits due to solid state diffusion. It is only at these pits that conduction through the Schottkybarrier is possible. Since the area of the pits constitutes only a portion of the total area, only a portion of the surface will partake in conduction. Contact resistance is always present. For pm sized contacts on integrated circuits, the spesific resistance is of the order of 10 -6 Q.cm2. Contacts on solar cells, however, are of millimetre dimensions and the spesific resistance can be four orders of magnitude larger. The conduction through the surface can be modelled as conduction through a surface that is constituted of a mixture of minute ohmic and diode surfaces.
"The effect of temperature, time and gas flow rate on the growth and characterization of Cu(In,Ga)Se₂ (CIGS) absorbers for thin film solar cells". Thesis, 2008. http://hdl.handle.net/10210/1361.
Testo completoCurrent solar cell research programmes in general aim to develop a high conversion efficiency photovoltaic (PV) module from high quality thin films. In this study, Cu (In,Ga)Se2 (CIGS) thin films were grown and characterized. These films were grown by selenization of Cu-In-Ga precursors. These precursors were prepared by co-sputtering In and (Cu, Ga). All the precursors were grown on Mo coated soda lime glass substrates. The selenization was conducted under different conditions in Ar/H2Se atmosphere, i.e. taking different values of flow rate of H2Se (5.00, 1.00, 0.25 mol%) in Ar, temperature (350, 450, 550 ºC) and time (10, 20, 30, 40, 50, 60 min). At each selenization condition, two samples were placed at different positions in the chamber. The structural properties of the produced films were analyzed by the techniques of X-ray Diffraction (XRD) for phases, Scanning Electron Microscopy (SEM) for morphology and Energy Dispersive Spectroscopy (EDS) for the bulk composition. The effect of temperature variation, the effect of flow rate variation and the effect of time variation were analyzed by comparing the structural properties as analyzed by the techniques mentioned. All in all this specific study delivers important information about the sensitivity of Cu(In,Ga)Se2 (CIGS) thin films to the temperature, gas flow rate and exposure time of the selenization step.
Doctor C.A. Engelbrecht Professor Vivian Alberts
Marques, Miguel João Bolacha. "New insights into perovskite semiconductors for electronic applications". Master's thesis, 2019. http://hdl.handle.net/10362/94397.
Testo completoEgilmez, Mehmet. "Magnetotransport and magnetoresistive anisotropy in perovskite manganites". Phd thesis, 2009. http://hdl.handle.net/10048/421.
Testo completoTitle from pdf file main screen (viewed on July 13, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Physics, University of Alberta." Includes bibliographical references.
Hemati, Azadeh. "LAYER BY LAYER NANOASSEMBLY OF COPPER INDIUM GALLIUM SELENIUM (CIGS) NANOPARTICLES FOR SOLAR CELL APPLICATION". 2011. http://hdl.handle.net/1805/2923.
Testo completoIn this research thesis, copper indium gallium selenium (CIGS) nanoparticles were synthesized from metal chlorides, functionalized to disperse in water, and further used in layer by layer (LbL) nanoassembly of CIGS films. CIGS nanoparticles were synthesized through the colloidal precipitation in an organic solvent. The peak and average sizes of the synthesized particles were measured to be 68 nm and 75 nm in chloroform, and 30 nm and 115 nm in water, respectively. Two methods were used to disperse the particle in water. In the first method the stabilizing agent oleylamine (OLA) was removed through multiple cleaning processes, and in the second method ligand exchange was performed with polystyrene sulfonate (PSS). Zeta potential of CIGS nanoparticles dispersed in water was measured to be +61 mV. The surface charge of the nanoparticles was reversed by raising the pH of the solution, which was measured to be −43.3 mV at 10.5 pH. In a separate process, the CIGS nanoparticles dispersed in water were coated with PSS. The resulting dispersion was observed to be stable and the surface charge was measured to be −56.9 mV. The LbL deposition process of CIGS nanoparticles was characterized by depositing thin films on quartz crystal microbalance (QCM). LbL depositions was conducted using (i) oppositely charged CIGS nanoparticles, (ii) positively charged CIGS nanoparticles and PSS, and (iii) PSS-coated CIGS (CIGS-PSS) and polyethyleneimine (PEI). The average thickness of each bi-layer of the above mentioned depositions were measured to be 2.2 nm, 1.37 nm, and 10.12 nm, respectively. The results from the QCM have been observed to be consistent with the film thickness results obtained from atomic force microscopy (AFM). Various immersion times versus thickness of the film were also studied. For electrical characterization, the CIGS films were deposited on indium tindioxide (ITO)-coated glass substrates. Current versus voltage (I/V) measurements were carried out for each of the films using the Keithley semiconductor characterization instruments and micromanipulator probing station. It was observed that the conductivity of the films was increased with the deposition of each additional layer. The I/V characteristics were also measured under the light illumination and after annealing to study the photovoltaic and annealing effects. It was observed that under light illumination, the resistivity of a 12-layer CIGS film decreased by 93% to 0.54 MΩ.m, and that of the same number of layers of PSS-coated CIGS and PEI film decreased by 60% to 0.97 MΩ.m under illumination. The resistivity of an 8-layer CIGS and PSS film decreased by 76.4% to 0.1 MΩ.m, and that of the same layers of PSS-coated CIGS and PEI decreased by 87% to 0.07 MΩ.m after annealing. The functionalized nanoparticles and the LbL CIGS films were implemented in the solar cell devices. Several configurations of CIGS films (p-type), and ZnO and CdS films (n-type) were considered. Poly(3,4-ethylenedioxythiophene) (PEDOT), molybdenum (Mo), and ITO were used as back contacts and ITO was used as front contact for all the devices. The devices were characterized the Keithley semiconductor characterization instruments and micromanipulator probing station. For a CIGS and n-ZnO films device with PEDOT as back contact and ITO as front contact, the current density at 0 V and under light illumination was measured to be 60 nA/cm2 and the power density was measured to be 0.018 nW/cm2. For a CIGS and CdS films device with ITO as both back and front contact, the current density at 0 V and under light illumination was measured to be 50 nA/cm2 and the power density was measured to be 0.01 nW/cm2. For a drop-casted CIGS and CdS films device with Mo as back contact and ITO as front contact, the current density of 50 nA/cm2 at 0 V and power density of 0.5 nW/cm2 under light illumination was measured. For the LbL CIGS and chemical bath deposited CdS films device with ITO as both back and front contact, the current density of 0.04 mA/cm2 at 0 V and power density of 1.6 μW/cm2 under light illumination was measured. Comparing to Device-III, an increase by 99% in the power density was observed by using the CIGS LbL film in the device structure. The novel aspects of this research include, (i) functionalization of the CIGS nanoparticles to disperse in water including coating with PSS, (ii) electrostatic LbL deposition of CIGS films using oppositely charged nanoparticles and polymers, and (iii) the utilization of the fabricated LbL CIGS films to develop solar cells. In addition, the n-type cadmium sulfide film (CdS) and zinc oxide (ZnO) buffer layer were also deposited through LbL process after the respective particles were functionalized with PSS coating in separate experiments.
Mugdur, Prakash. "Continuous flow microreactor for chemical bath deposition : a novel approach to the deposition of polycrystalline semiconductor thin films". Thesis, 2005. http://hdl.handle.net/1957/32160.
Testo completoGraduation date: 2005
Chang, Fang-Long, e 張芳龍. "Analyses of High-Performance Integrated Power Lateral Double-Diffused Metal-Oxide-Semiconductor Field-Effect-Transistors Fabricated on Single Crystalline and Low Temperature Polycrystalline Silicon Materials". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/g2etmd.
Testo completo國立交通大學
電子工程系所
92
In this dissertation, for the sake of system-on-a-chip (SOC), silicon-on-insulator (SOI) and Bipolar-CMOS-DMOS (BCD) technology have been studied because of its superior isolation characteristics and mixture of the analog functions of bipolar, digital design of CMOS and high-voltage elements of DMOS on the same chip. In order to improve breakdown voltage from less reduced-surface-field (RESURF) effect of SOI devices, the step doping profile are investigated instead of complicated linearly graded doping profile by the distinct doping region along lateral direction. In order to stride forward the future integrations on any substrates, the LTPS LDMOS using excimer laser crystallization has been demonstrated by combination of the thin film technology and power device architecture. The LTPS LDMOS at 400 C substrate heating during excimer laser annealing will be used to expect to be a future driver device in system-on-a-panel (SOP) and three-dimensional (3-D) circuit integrations. Additionally, in order to comprehend heat dissipation in 3-D integration circuits, analyses of thermal problems in 3-D circuits are necessary. First, traditional Bipolar-CMOS-DMOS (BCD) technology, which is designed for only lateral bipolar (Bipolar, 12 V BVCEO and 25 V BVCBO), complementary metal oxide semiconductor (CMOS, 1.2 V threshold voltage) and double diffused metal oxide semiconductor (DMOS, 40 V breakdown voltage) transistors on the bulk silicon wafer, has been successfully utilized directly to fabricate silicon-on-insulator lateral-double -diffused-metal-oxide-semiconductor (SOI LDMOS) for the first time without changing any trial parameters. To simultaneously display the characteristics of high-power, high-speed and high-frequency, the results of output characteristics, switch and microwave performance must be moderate instead of individual optimum. Finally, according to the experimental results, it is proved that Bulk-BCD technology simultaneously enables high speed, high frequency and high blocking voltage applications�osuch as those in high-voltage integrated circuit switches (ns-range) and RF power amplifiers (MHz range to GHz range)�ousing a SOI wafer. In the study of step doping profile, a partition method is proposed to analyze the high-voltage step-doping silicon on insulator lateral insulated gate bipolar transistor (Step-Doping SOI-LIGBT) structure. The on-state characteristics will be present with the similar forward voltage drop (Vce) value between the step doping and linearly graded doping devices. The breakdown voltage can be deduced by the partition mid-point method and the corresponding breakdown electric field will also be fingered out in the step drift region. Furthermore, in order to reduce the undesirable additional masks, the degraded factor (D) is developed to evaluate the minimum number of frames with the better performance. Eventually, a 660 V step analytical results will be exemplified to compare with a 606.6 V MEDICI simulation, which shows very good agreement by this proposed method. In the study of future SOP and 3-D integrations, a new low-temperature polycrystalline silicon high-voltage LDMOS (LTPS HVLDMOS) using excimer laser crystallization has been proposed for the first time. However, in order to enhance LTPS HVLDMOS characteristics, there are two starting points: 1) integrate the thin film technology with the power device, 2) clarify the requirement of excimer laser treatment for low temperature power devices. As a result, the ON/OFF current ratio after laser treatment is improved over 106 times than that before laser treatment at Ldrift=15-�慆 and Vds=25 V. The LTPS HVLDMOS after laser treatment also demonstrates the better trade-off between the specific on resistance and breakdown voltage against the previous HVTFTs by solid phase crystallization�osuch as semi-insulating (SI), metal-field-plated (MFP), and offset-drain (OD) HVTFTs. In order to further improve the quality of crystallized poly-Si thin films and the performance of LTPS LDMOS, low-temperature poly-Si lateral double diffused metal oxide semiconductor (LTPS LDMOS) with high voltage and very low on-resistance has been achieved using excimer laser crystallization at 400 �aC substrate heating for the first time. The ON/OFF current ratios were exhibited with 2.96 × 10^5 and 6.72 × 10^6 while operating at Vds=0.1 V and 10 V, respectively. The maximum current limit was up to 10 mA and maximum power limit could be enhanced over 1 Watt at Vds=90 V and Vgs=20 V. The Ron,sp with dimensions of W/Lch=600-um/12-um could be significantly decreased 6.67 × 102 times in the magnitude as compared with the traditional offset drain (OD) TFTs. At last part of this thesis, the issue of heat dissipation will be discussed because many potential applications require operation at elevated temperatures. The effects of a high temperature ambient are exacerbated by power dissipation which causes additional temperature rise within the device. Power devices are often expected to run hotter than other component, but the excessive temperature rise of an inherently problem device will often lead to catastrophic failure. Failure of a single power device can shut down a computer, bring to halt a motor-driven system, or stop a vehicle dead in its tracks. This problem is anticipated to be exacerbated in 3-D circuit integration because the same power generated in a 2-D chip will now be generated in a smaller 3-D chip size resulting in a sharp increase in the power density. Therefore, accurate characterization of the thermal properties of power transistors is critical to the reliability of the systems using these devices. In order to understand this problem, the different electrical characteristics between crystalline and polycrystalline high voltage devices will be studied and the thermal stability of the LTPS LDMOS between the room temperature and 400 C irradiation will also be discussed over the ambient temperatures of 300 K�{400 K. The results of ambient temperature variation in LTPS LDMOS at 400 C irradiation are demonstrated the less sensitivity than the LTPS LDMOS before laser irradiation and at room temperature irradiation. Hence, the LTPS LDMOS at 400 C irradiation is very suitable for future system-on-a-panel (SOP) applications with higher temperature reliability.