Дисертації з теми "Amorphous Silica Surface"
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Chen, Si-Han. "Molecular Dynamics Investigation of Surface Potential andElectrokinetic Phenomena at the Amorphous Silica/WaterInterface." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1534510054324125.
Повний текст джерелаWilmsmeyer, Amanda Rose. "Ultrahigh Vacuum Studies of the Fundamental Interactions of Chemical Warfare Agents and Their Simulants with Amorphous Silica." Diss., Virginia Polytechnic Institute and State University, 2012. http://hdl.handle.net/10919/54366.
Повний текст джерелаPh. D.
Arancon, Rick Arneil. "Exploration of Transition Metal Sulfide Catalysts Prepared by Controlled Surface Chemistry." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEN063.
Повний текст джерелаHydrotreating is an important catalytic process in petroleum refining which uses sulfided bimetallic catalysts NiWS or NiMoS (or CoMoS) supported on alumina. Their conventional preparation involves an incipient wetness impregnation of an aqueous solution of Mo/W and Ni/Co salts, and then activation by a sulfo-reductive agent (such as H2S/H2). To meet environmental regulations and improve the energy efficiency of hydrotreatment, permanent improvements on the performance of these catalytic systems are expected. This work is thus focused on the preparation of highly active hydrotreating catalysts through a controlled surface chemistry (CSC) approach; which involves the successive impregnation of Mo5+ and Ni2+ molecular precursors in an organic solvent on a thermally treated silica-alumina support. In the first part of this thesis, the active phase genesis of CSC and conventional Mo and NiMo catalysts is studied by in situ quick-XAS combined with various other techniques (chemometrics, XPS, EPR, STEM-HAADF, molecular modeling). We thus propose molecular structures from the oxide of supported Mo and Ni precursors up to the numerous intermediate sulfided species as a function of temperature. This multi-technique analysis enables first to reveal the specific features of the genesis of CSC and conventional catalysts which may explain their different catalytic activities. Then, it also reveals new insights into the mechanisms of Ni promoter incorporation into the NiMoS phase as a function of the preparation. In the second part, the feasibility of replacing Co and Ni as promoters is explored. Using the CSC method, we attempted to synthesize alternative catalysts of the form XYMoS ternary sulfides, where X and Y are 3d transition metals. As suggested by previous quantum simulations, certain XY formulations possibly reveal a synergy effect as observed in CoMoS and NiMoS active phases. The most promising formulations merit further investigations
Lund, Christopher Paul. "Surface spectroscopy and Auger lineshape analysis studies of amorphous silicon surfaces." Thesis, Lund, Christopher Paul (1993) Surface spectroscopy and Auger lineshape analysis studies of amorphous silicon surfaces. PhD thesis, Murdoch University, 1993. https://researchrepository.murdoch.edu.au/id/eprint/42221/.
Повний текст джерелаFerré, Tomàs Rafel. "Surface passivation of crystalline silicon by amorphous silicon carbide films for photovoltaic applications." Doctoral thesis, Universitat Politècnica de Catalunya, 2008. http://hdl.handle.net/10803/6350.
Повний текст джерелаActualment la indústria fotovoltaica empra capes de nitrur de silici crescut mitjançant la tècnica PECVD. Com a alternativa, es presenta el carbur de silici amorf (a-SiC), també crescut mitjançant PECVD. Resultats anteriors mostren que la passivacio del silici a partir de carbur de silici amorf son excel·lents quan el material és ric en silici i dopat amb fòsfor. L'alt contingut en silici provoca absorció de la llum a la capa, que no es tradueix en corrent elèctric, fent d'aquesta manera que el material sigui només útil quan s'aplica a la cara no il·luminada de la cèl·lula.
L'objectiu d'aquesta tesi és millorar les propietats de passivació del carbur de silici afegint els requisits indispensables en cèl·lules solars: uniformitat, transparència i propietats antireflectants, estabilitat a llarg termini i enfront altes temperatures. A part de les aplicacions tecnològiques també es pretèn entendre millor les propietats fonamentals de passivació.
Els principals resultats són:
- La passivació millora a mesura que s'incrementa el gruix de la capa de a-SiC, fins arribar a una saturació a partir de 50 nm. El mecanisme responsable es una millor saturació dels defectes de la interficie amb hidrogen. Al contrari del que es pensava a priori, la càrrega el·lèctrica emmagatzemada a la capa es manté constant amb el gruix.
- Experiments amb "corona charge" indiquen que l'origen de la càrrega el·lèctrica que produeix la passivació per efecte de camp es troba en la densitat d'estats a la interfície.
- No ha estat possible trobar una capa tranparent (rica en carboni) amb bona passivació. La millor aproximació per combinar passivació més transparència és emprar dues capes, una molt prima rica en silici per passivar i l'altra rica en carboni per aconseguir les propietats antireflectants adequades. S'ha optimitzat el gruix de la capa rica en silici per aconseguir un compromís entre la pèrdua de corrent degut a l'absorció de la llum a la capa i les propietats de passivació. Aquesta combinació de doble capa s'ha fet servir per passivar bases tipus p i emissors tipus n amb resultats excel·lents. Finalment, amb la doble capa es va poder fabricar la primera cèl·lula passivada amb carbur de silici amb una eficiencia > 20%.
- S'ha desenvolupat un material nou: l'al·leació de silici, carboni i nitrogen dopada amb fòsfor. Aquest material ha donat els millors resultats de passició fins ara obtingut dins el nostre grup en bases tipus p i tipus n i en emissors tipus n. La composició òptima és rica en silici i la combinació de capes dobles amb diferents composicions, com en el cas anterior, torna a donar bons resultats de passivació i transparència.
- S'han desenvolupat experiments d'estrès tèrmic a alta temperatura. Les propietats de passivació es veuen fortament afectades desprès de l'estrès si les capes són riques en silici. D'altra banda, les dobles capes mostren una estabilitat molt més alta a l'estrès tèrmic.
The thesis focuses on the study of surface passivation of crystalline silicon to produce high efficiency solar cells (with conversion efficiencies > 20%) at reduced prices. The state of the art in surface passivation is done by thin films of amorphous silicon nitride grown by Plasma Enhanced Chemical Vapour Deposition (PECVD) and it is a very well established material in the photovoltaic field.
In this thesis we offer an alternative that is based on amorphous silicon carbide (a-SiC), also grown by PECVD. The passivation properties of silicon carbide have been already studied in our group finding that excellent results can be obtained when the films are rich in silicon, especially for those doped with phosphorus to make a n-type material. Because this feature leads to undesirable absorption of solar light within the films that does not contribute to the photocurrent, silicon carbide would then be relegated to passivate only the rear side of the solar cell.
The aim of this work is to improve surface passivation properties developed previously and add compulsory requisites for the application of crystalline solar cells. These requisites are: uniformity, transparency and antireflective properties, stability under long term operation and stability under high temperature steps (allowing screen printing processes). Also it is the willing to provide a better understanding of the fundamental properties.
The main results achieved are enumerated hereafter:
- Surface passivation improves with the film thickness and then saturates for films thicker than 50 nm. The mechanism responsible for this improvement is not an increase of the electric charge in the film, as in principle could be thought, but a better saturation of defects by the presence of hydrogen. The amount of charge density seems to be independent of the film.
- Experiments of corona charge reveal some treats about the nature of the charge density to provide the field effect passivation. The origin of the charge seems to be a continuous density of states at the interface, rather a fixed charge allocated in the film.
- None of the attempts using carbon rich films, which are transparent and with antireflective properties, resulted in excellent surface passivation. Such attempts included variation of the deposition parameters, use of remote plasma PECVD with high incorporation of hydrogen, and introduction of nitrogen of in the phosphorus doped a-SiC films. Therefore, up to now it becomes apparent that it is a fundamental property of silicon carbide films the necessity to be rich in silicon to perform surface passivation.
- The way to combine surface passivation and antireflective properties was applying stacks of different a-SiC layers: one silicon rich and one carbon rich. The thickness of the silicon rich layer was optimized to reach a trade-off between level of passivation and lost of photocurrent due to the absorption in the film. The stacks were used to passivate p-type bases, with reasonably good results, and n+- type emitters, with very good results. The stacks provided the the first silicon solar a-SiC rear side passivated with efficiency above 20%.
- A new material was tested: a ternary alloy of silicon, carbon and nitrogen doped with phosphorus. This material was applied to n- and p-type bases and n+-type emitters, presenting the best results in surface passivation achieved by our group, and comparable to surface passivation record achieved by amorphous silicon carbide. Best composition was rich in silicon, and again stacks of silicon rich and carbon rich films was combined successfully.
- Stability against thermal processes was tested on different passivation schemes. After the treatment, the passivation is strongly reduced for single silicon rich films, which were offering good initial results. On the other hand, the stacks with a second carbon rich film maintain reasonably well the surface passivation properties.
Almeida, Serrita Avril. "Modification of amorphous silicon nitride surfaces by ion implantation of gallium." Thesis, University of Surrey, 1999. http://epubs.surrey.ac.uk/843307/.
Повний текст джерелаSuwito, Dominik [Verfasser]. "Intrinsic and doped amorphous silicon carbide films for the surface passivation of silicon solar cells / Dominik Suwito." München : Verlag Dr. Hut, 2011. http://d-nb.info/1011441772/34.
Повний текст джерелаLabrune, Martin. "Silicon surface passivation and epitaxial growth on c-Si by low temperature plasma processes for high efficiency solar cells." Phd thesis, Ecole Polytechnique X, 2011. http://pastel.archives-ouvertes.fr/pastel-00611652.
Повний текст джерелаCarteret, Cédric. "Etude, par spectroscopie dans le proche infrarouge, et modélisation des structures de surface et de l'hydratation de silices amorphes." Nancy 1, 1999. http://www.theses.fr/1999NAN10238.
Повний текст джерелаPepenene, Refuoe Donald. "Macroscopic and Microscopic surface features of Hydrogenated silicon thin films." University of the Western Cape, 2018. http://hdl.handle.net/11394/6414.
Повний текст джерелаAn increasing energy demand and growing environmental concerns regarding the use of fossil fuels in South Africa has led to the challenge to explore cheap, alternative sources of energy. The generation of electricity from Photovoltaic (PV) devices such as solar cells is currently seen as a viable alternative source of clean energy. As such, crystalline, amorphous and nanocrystalline silicon thin films are expected to play increasingly important roles as economically viable materials for PV development. Despite the growing interest shown in these materials, challenges such as the partial understanding of standardized measurement protocols, and the relationship between the structure and optoelectronic properties still need to be overcome.
Lane, Christopher Don. "Low-Energy Electron Induced Processes in Molecular Thin Films Condensed on Silicon and Titanium Dioxide Surfaces." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14588.
Повний текст джерелаBharadwaja, Saketh. "Molecular Dynamics Simulations of Si binding and diffusion on the native and thermal Silicon Oxide surfaces." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1333738718.
Повний текст джерелаMartin, de Nicolas Silvia. "a-Si : H/c-Si heterojunction solar cells : back side assessment and improvement." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112253/document.
Повний текст джерелаAmongst available silicon-based photovoltaic technologies, a-Si:H/c-Si heterojunctions (HJ) have raised growing attention because of their potential for further efficiency improvement and cost reduction. In this thesis, research on n-type a-Si:H/c-Si heterojunction solar cells developed at the Institute National de l’Énergie Solaire is presented. Technological and physical aspects of HJ devices are reviewed, with the focus on the comprehension of the back side role. Then, an extensive work to optimise amorphous layers used at the rear side of our devices as well as back contact films is addressed. Through the development and implementation of high-quality intrinsic and n-doped a-Si:H films on HJ solar cells, the needed requirements at the back side of devices are established. A comparison between different back surface fields (BSF) with and without the inclusion of a buffer layer is presented and resulting solar cell output characteristics are discussed. A discussion on the back contact of HJ solar cells is also presented. A new back TCO approach based on boron-doped zinc oxide (ZnO:B) layers is studied. With the aim of developing high-quality ZnO:B layers well-adapted to their use in HJ devices, different deposition parameters as well as post-deposition treatments such as post-hydrogen plasma or excimer laser annealing are studied, and their influence on solar cells is assessed. Throughout this work it is evidenced that the back side of HJ solar cells plays an important role on the achievement of high efficiencies. However, the enhancement of the overall device performance due to the back side optimisation is always dependent on phenomena taking place at the front side of devices. The use of the optimised back side layers developed in this thesis, together with improved front side layers and a novel metallisation approach have permitted a record conversion efficiency over 22%, thus demonstrating the great potential of this technology
Ross, Nick. "Interfacial Electrochemistry of Cu/Al Alloys for IC Packaging and Chemical Bonding Characterization of Boron Doped Hydrogenated Amorphous Silicon Films for Infrared Cameras." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc849696/.
Повний текст джерелаNgandjong, Alain Cabrel. "Modélisation structurale des clusters d’alliages supportés : effet du support de silice et effet de taille." Thesis, Orléans, 2015. http://www.theses.fr/2015ORLE2070/document.
Повний текст джерелаNumerical simulations have so far neglected the influence of amorphous silica substrate on the structure of metallic nanoparticles due to its relatively weak interaction with deposited nanoparticles. However, experimental studies have often shown a truncation effect on the structure of nanoparticles. The idea of this work was to study the influence of this substrate on the structure of silver nanoparticles using molecular modeling (Monte Carlo and molecular dynamics). The objective of this work was firstly to determine silver-silica interatomic potential. This was achieved using experimental data of wetting angles in solid and liquid phase. On the other hand, silver-silica interaction intensity was determined by DFT calculations on cristobalite which is a polymorph of crystalline silica having the same density as amorphous silica. The adhesions energies obtained were used to fit the Lennard-Jones parameters for the silver-silica interaction. The study of the structural stability of silver nanoparticles supported at zero temperature was performed for three levels of approximation of the support. (1): the smooth wall approximation where the support is described by a square-well whose depth is related to the adhesion energy of the nanoparticle, (2): an atomistic model of flat amorphous silica, (3): an atomistic model of rough amorphous silica. The influence of the temperature on the structure was investigated by melting and recrystallization of the silver nanoparticles deposited on the two silica supports. In order to study the temperature stability of the nanoparticles the free energy calculation of the nanoparticles was discussed
Sahli, Salah. "Etude du comportement electrique de films minces de gaas amorphes ou polycristallins elabores par depots en phase vapeur ou par plasma a partir d'organometalliques." Toulouse 3, 1986. http://www.theses.fr/1986TOU30049.
Повний текст джерелаMitchell, Jonathon Drew. "Application of amorphous silicon for photovoltaic silicon surface passivation." Phd thesis, 2011. http://hdl.handle.net/1885/151789.
Повний текст джерелаStepanov, Dmitri. "Surface Passivation of Crystalline Silicon by Dual Layer Amorphous Silicon Films." Thesis, 2011. http://hdl.handle.net/1807/29630.
Повний текст джерелаlee, Hsueh-Chuan, and 李學銓. "Surface passivation of silicon heterojunction using hydrogenated amorphous silicon oxide layers." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/p2kxf5.
Повний текст джерела國立臺灣科技大學
化學工程系
100
In this paper, we studied the passivation quality of intrinsic amorphous silicon sub-oxides (a-SiOx:H) thin layers deposited on n-type FZ Si wafers. Conventional RF plasma enhanced chemical vapor deposition (RF-PECVD) system were applied to deposit a-SiOx:H using SiH4, CO2, and H2 as the reactant gases. We investigated to effects of passivation quality of c-Si wafers sandwiched by 30-nm thick a-SiOx:H layers deposited at various CO2 partial pressures. We found that by increasing the CO2 concentration from 0.1 to 0.5% the corresponding effective carrier lifetime of Si wafers increase from 1100 to 2360s, and the implied open circuit voltage increase from 608 to 740 mV. Optical analysis of the a-SiOx:H layers showed that the addition of CO2 concentration from 0.1 to 0.5% increase the optical band gap of a-SiOx:H layers from 1.72 to 1.85eV. The application of the a-SiOx:H layer with 1.85eV band gap to the fabrication of Si heterojunction solar cells showed a high cell Voc of 707mV.
Coffee, Shawn Stephen 1978. "Selective silicon and germanium nanoparticle deposition on amorphous surfaces." Thesis, 2007. http://hdl.handle.net/2152/3181.
Повний текст джерелаtext
Lee, Ken-Hsuan, and 李耿亘. "Surface Passivation of Germanium Wafers using Hydrogenated Amorphous Silicon Layers." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/66857266560171042056.
Повний текст джерела國立臺灣科技大學
化學工程系
102
In this paper, we studied several important issues concerning fabrication of crystalline germanium (Ge) hetero-junction using amorphous Si as the passivation layers. First of all, surface cleaning procedure of Ge wafers was established through a comparison with the conventional RCA cleaning procedure for Si wafers. An efficient way for surface cleaning of Ge included a series of organic solvents, HCl, and HF treatments with suitable concentrations. Then, a surface oxide layer was fabricated with intention through an immediate dipping in H2O2 solution after HF treatment. Finally a very clean Ge(100) was obtained, which was verified by RHEED, by removing the oxide layer using thermal annealing in a high vacuum chamber at temperatures ranging 450 ℃. After surface cleaning process, we use PECVD to grow 16 nm hydrogenated amorphous silicon (a-Si:H) for germanium surface passivation. The best minority carrier lifetime of the Ge wafer after a-Si:H double-side coated was 291.3 μs, which was further reduced to 112.7 μs after completion of n+ a-Si:H/i a-Si:H/c-Ge/i a-Si:H/p+ a-Si:H.
"Surface passivation of crystalline silicon by amorphous silicon carbide films for photovoltaic applications." Universitat Politècnica de Catalunya, 2008. http://www.tesisenxarxa.net/TDX-0428108-125947/.
Повний текст джерелаLeong, Keith R. "Characterization of surface passivation of crystalline silicon by hydrogenated amorphous silicon using photocarrier radiometry." 2006. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=442187&T=F.
Повний текст джерелаPlagwitz, Heiko [Verfasser]. "Surface passivation of crystalline silicon solar cells by amorphous silicon films / von Heiko Plagwitz." 2007. http://d-nb.info/98648735X/34.
Повний текст джерела"Large Area Ultrapassivated Silicon Solar Cells Using Heterojunction Carrier Collectors." Doctoral diss., 2013. http://hdl.handle.net/2286/R.I.20907.
Повний текст джерелаDissertation/Thesis
Ph.D. Electrical Engineering 2013
Lin, Hung-Ting, and 林宏庭. "Surface Passivation of Silver-Assisted Etched MGSC by Using Hydrogenated Amorphous Silicon Film." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/27421821857100264160.
Повний текст джерелаd’Orey, Maria da Piedade Oom de Albuquerque. "Functionalization of Silica Surfaces: Influence in Naproxen Molecular Mobility and Release Profile." Master's thesis, 2018. http://hdl.handle.net/10362/57825.
Повний текст джерелаPetres, Roman [Verfasser]. "Amorphous silicon compound films for surface passivation and antireflection coating of crystalline silicon solar cells / vorgelegt von von Roman Petres." 2010. http://d-nb.info/1009417452/34.
Повний текст джерелаJacobs, Sulaiman. "Optical properties of annealed hydrogenated amorphous silicon nitride (a-SiNx:H) thin films for photovoltaic application." 2013. http://hdl.handle.net/11394/3588.
Повний текст джерелаTechnological advancement has created a market for large area electronics such as solar cells and thin film transistors (TFT’s). Such devices now play an important role in modern society. Various types of conducting, semiconducting and insulating thin films of the order of hundreds, or even tens of nanometres are combined in strata to form stacks to create interactions and phenomena that can be exploited and employed in these devices for the benefit of mankind. One such is for the generation of energy via photovoltaic devices that use thin film technology; these are known as second and third generation solar cells. Silicon and its alloys such as silicon germanium (SiGex), silicon oxide (SiOx), silicon carbide (SiCx) and silicon nitride (SiNx) play an important role in these devices due to the fact that each material in its different structures, whether amorphous, micro or nano-crystalline or completely crystalline, has its own range of unique optical, mechanical and electrical properties. These structures and their material properties can thus exert a huge influence over the overall device performance. viii Chemical vapour deposition (CVD) techniques are most widely used in industry to obtain thin films of silicon and silicon alloys. Source gases are decomposed by the external provision of energy thereby allowing for the growth of a thin solid film on a substrate. In this study a variant of CVD, namely Hot Wire Chemical Vapour Deposition (HWCVD) will be used to deposit thin films of silicon nitride by the decomposition of silane (SiH4), hydrogen (H2) and ammonia (NH3) on a hot tantalum filament (~1600 C). Hydrogenated amorphous silicon nitride (a-SiNx:H) has great potential for application in optoelectronic devices. In commercial solar cell production its potential for use as anti-reflection coatings are due to its intermediate refractive index combined with low light absorption. An additional benefit is the passivation of interface and crystal defects due to the bonded hydrogen. This can lead to better photon conversion efficiency. Its optical properties including optical band gap, Urbach tail, and wavelength-dependent optical constants such as absorption coefficient and refractive index are crucial for the design and application in the relevant optoelectronic device. The final firing step in the production of micro-crystalline silicon solar cells, allows hydrogen to effuse into the solar cell from the a-SiNx:H, and drives bulk passivation of the grain boundaries. We therefore propose the exploration of annealing effects on the thin film structure. The study undertakes a comparison of optical and bonding structure of the as deposited thin film compared to that of the annealed thin film which would have undergone changes due to high temperature annealing under vacuum. However, it is difficult to simultaneously obtain all of these important ix optical parameters for a-SiNx:H thin films. Ultraviolet visible (UV-vis) spectroscopy will be the method of choice to investigate the optical properties. Infrared (IR) spectroscopy is a source of useful information on the microstructure of the material. In particular, the local atomic bonding configurations involving Si, N, and H atoms in a-SiNx:H films can be obtained by Fourier Transform Infrared Spectroscopy (FTIR). Therefore, this study will attempt to establish a relationship between film microstructure of a-SiNx:H thin films and their macroscopic optical properties.
Lin, Hung-Yu, and 林紘宇. "Simulation on Absorption Enhancement of a Thin-Film Amorphous Silicon Solar Cell through Surface Plasmon Coupling with a Metal Grating." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/48490148999840118828.
Повний текст джерела國立臺灣大學
光電工程學研究所
99
By using the commercial software COMSOL Multiphysics which is based on the finite element method (FEM), the absorption effects of the thin-film amorphous silicon solar cell with one-dimensional or two-dimensional metal grating structures are numerically investigated. The solar cell structure consists of three parts: an ITO layer as the top contact, an amorphous silicon layer and a metal Ag grating layer as the back contact. The light source adopted is with the AM1.5G solar spectrum, and different incident angles and grating heights are changed to investigate the influences on the absorption of the solar cell. The thin-film solar cell with metal grating back contact can form the graded-refractive index layer on the surface. Based on the characteristic of the amorphous silicon, the poorly absorbed red light can couple into the surface plasmon mode in the back metal grating contact. The absorption of the solar cell can be enhanced due to the generation of surface wave resonance and scattering. The device combines advantages of both reduced reflection and enhanced absorption over a broad spectral range. The solar cells with the grating structures compared with the reference case of a flat metal surface back contact. The absorption enhancement of the solar cell can reach 56% at best with the appropriate grating design.
Anahory, Yonathan. "Mécanismes de recuit dans le silicium implanté par faisceau d’ion caractérisés par nanocalorimétrie." Thèse, 2010. http://hdl.handle.net/1866/4657.
Повний текст джерелаWe present the fabrication process, characterization and numerical model allowing the optimization of a new device that allows us to perform nanocalorimetry measurements on a silicon single crystals. The thermal properties of this device allows us to perform measurements at temperature higher than 900 C with a resolution better than 16 C. The device is used to study the ion implantation induced defect dynamic in monocrystalline silicon. Two different behaviours regarding the nucleation of the amorphous phase are observed at 10 and 80 keV. These results are confronted to Monte Carlo simulations based on the interstitial vacancy pair model. The comparison between simulations and measurements show that the model is incomplete as it reproduces only qualitatively some features of the experimental observations. Measurements performed from -110 C in monocrystalline and amorphized silicon implanted with light ions revealed clear differences between structural relaxation in amorphous silicon and defect annealing in monocrystalline silicon. Two processes with activation energies of 0.48 and 0.6 eV are observed after implantation performed in monocrystalline silicon while a uniform heat release associated with a continuous spectrum in terms of activation energy is observed in amorphous silicon.
Kallel, Houssem. "Effets de la concentration des défauts sur la surface d'énergie potentielle du silicium amorphe." Thèse, 2008. http://hdl.handle.net/1866/8027.
Повний текст джерела