This thesis presents results on the applications and limitations of plasma enhanced chemical vapour deposition for silicon-based photonics, with an emphasis on optical microcavities for the control of light emission from silicon nanocrystals. ¶ Silicon nanocrystals were formed by precipitation and growth within Si-rich oxide layers (SiOx) deposited by plasma enhanced chemical vapour deposition. The films were found to exhibit strong room temperature photoluminescence, with the optimum emission depending on the composition and processing of the films. The strongest emission was achieved for films with a silicon content of ~40%, following hydrogen passivation. Hydrogen was introduced into the samples by two different methods: by annealing in forming gas (95% N2: 5% H2) or by annealing with a hydrogenated silicon nitride capping layer. Both methods caused an increase in photoluminescence intensity due to the passivation of defects. In contrast, the presence of low levels of iron and gold were shown to reduce the concentration of luminescent nanocrystals due to the creation of non-radiative centres. ¶ Optical microcavity structures containing silicon nanocrystals were also fabricated by Plasma enhanced chemical vapour deposition, using silicon dioxide, silicon nitride and silicon-rich oxide layers. The microcavities consisted of a silicon-rich oxide layer between two distributed Bragg reflectors formed of alternating silicon dioxide/nitride layers. The optical emission from these and related structures were examined and compared with that from individual layers in the structure. This revealed a complex interplay between defect and nanocrystal luminescence, hydrogen passivation and materials structure. The resulting microcavity structures were shown to be suitable for producing a stop-band over the wavelength range of interest for nanocrystal emission, 500-1000nm, and to produce significant intensity enhancement and spectral narrowing. Quality factors of 50-200 were demonstrated. ¶ The application of plasma deposited films was shown to be limited by stress-induced failure that resulted in cracking and delamination of the films during annealing. The SiOx films thicker than about 600nm failed predominantly by cracking. This was shown to be caused by tensile stress in the film caused by hydrogen desorption during high temperature annealing. The resulting cracks showed preferred alignment depending on the crystallographic orientation of the silicon substrate. For films deposited on (100) silicon, two modes of crack propagation were observed, straight cracks aligned along < 100> directions, and wavy cracks aligned along < 110> directions. For films deposited on (110) silicon, straight cracks were observed along [-1 10] directions, with a lesser number aligned along [001] directions. Cracks were also observed for films on (111) silicon. These showed 3-fold symmetry consistent with crack propagation along < 211> directions due to plastic deformation. Details of these crack geometries and their dependencies are discussed.

近幾年再生能源的議題非常的熱門，各種再生能源產業的風力發電、太陽能電池、生質能、燃料電池等產業資料，相關創業與投資訊息不斷的傳播。各種科技看起來，好像都是明日之星。對於一個要準備創業的創業家，那一個產業那一個區間才是適合的機會？在投入創業前要透過何種有效的篩選工具才能選出適當的創業機會？ 本研究先從史考特‧夏恩(2005) 的科技創業聖經十個面向，再到創新者的解答與創新者的解答中的所提出的破壞性創新的觀念，先以質性研究的紮根理論探討檢視潛在創業產業及個案的可行性探討，對於經過第一階段質性研究考驗的個案，再以折價現金流量（Discount Cash-Flow）建立量化研究的財務模型，以求得資本內部報酬率（Equity Internal Return Ratio）及淨現金流量（Net Present Value）並以敏感性分析及情境分析探討財務可行性，期望找出一個創業機會能完全符合所有前訴的條件。本研究歷經三年的探討，檢視過數十個個案，包括風力發電、燃料電池、生質酒精、生質柴油、太陽能產業上中下游等創業機會，若要在台灣的環境創業又要提高創業成功機率，且又要能滿足創業團隊財務的報酬率的期望，能經過這麼多條件考驗的個案少之又少。 本研究最後選定以太陽能產業最上游的多晶矽改良式冶金法做為創業探討的個 案，最主要的原因是太陽能產業是屬於一種再生能源，有很大的機會成為長期高速成長的產業，且台灣因半導體產業及面板產業已為太陽能產業建立了基礎，多晶矽改良式冶金法又是一種破壞性創新，能提高創業成功的機會，且若在上游產業成功創業，能建立很高的進入障礙，對太陽能產業的發展佈局能具有策略性的地位。多晶矽改良式冶金法創業計畫在經過財務模型試算後，資本內部報酬率及淨現金流量，即使以改變投資條件進行創業投資的敏感性分析，或以不同情境進行探討，都能符合財務需求條件，仍能滿足創業投資的要求。 / Re-newable energy is very hot in these few years. There is lots of information mention about start-up and invest of renewable energy industry including win-power, solar-cell, bio-energy, fuel-cell. Seems every technology will be a future star industry. Which sector of what kind of re-newable energy technology will be the proper opportunity for an entrepreneur? What are effective tools to sieve the proper start-up chance out？ This research first using quality research grounding theories, this research verify proper industry and to find out the feasibility for the specific case. The technology management theories including , Shane’s （2005）「Find Fertile Ground – Indentifying Extraordinary Opportunities for New Ventures 」 10 procedures and Christensen ( 1997) 「 The innovator’s Dilemma 」、 Christensen & Raynor (2004) 「The innovator’s Solution：The creating and sustaining successful growth 」- Disruptive innovation technology theories . When the specific case through the quality detected, go to quantity study. Th quantity study include building a finance model,calculate Discount Cash-Flow, Equity Internal Return Ratio, Net Present Value, Sensitive analysis Senarial analysis to find out the financial feasibility. This research hopes to find out a suitable star-up opportunity which could pass all the examination items of quality and quantity study. This research through three whole years to search start-up opportunities., examed dozens cases, and the industies including win-power, solar-cell, bio-energy, fuel-cell and stream sector contain up-stream, middle-stream, down-stream After through this research process, shows that it is really hard to find out a suitable, profitable and could content the financial expection ratio with high win-odds opportunities to run start-up. After three years, this research finally pick up the solar upest-stream sector （modified metelology poly-silicon）as the research case. The first reason is that solar industry belongs to re-newable energy, which has strong protenial to become a long term and high conpound growing rate industy. The second reason：Taiwan have been developing semi- ductor and LCD industries over twenty years and built firmly industy knowledge foundation.Modified metelology poly-silicon is a disruptive innovation, could enlarge the start-up winodds. The third reason is that to start-up in the solar industy up-stream sector could build a high barrier and keep a strategy position in the solar industry. The third reason is that the financial result will fit in with the investor’s expect.

Graduation date: 1997

Les expériences conduites auprès du futur accélérateur LHC au CERN nécessitent la construction des détecteurs les plus grands et les plus complexes jamais conçus. En particulier, le trajectographe de la collaboration CMS utilisera uniquement des détecteurs micropiste silicium et ce, en très grandes quantités. Ce dernier dépend donc de manière capitale de la qualité de toute la production des senseurs et la collaboration CMS a ainsi décidé de mettre en place un vaste programme de contrôle de cette qualité. Cette thèse présente une partie des travaux réalisés à l'UCL dans ce cadre. La discussion porte en particulier sur résistance aux radiations des senseurs en silicium, testée de manière routinière à Louvain-la-Neuve. Le texte débute par une présentation du détecteur CMS et des dégâts radiatifs subits par les détecteurs micropiste silicium. Les dispositifs expérimentaux mis en place auprès des cyclotrons et dans le laboratoire de l'institut de Physique nucléaire sont ensuite détaillés. Finalement, les résultats des tests systématiques sont résumés, et discutés au regard des critères posés par la collaboration

In this work, we studied the possibility of synthesizing nanocrystalline germanium (Ge) via dry and wet oxidation of both amorphous and polycrystalline Si₀.₅₄Ge₀.₄₆ films. In dry oxidation, Ge was rejected from the growing SiO₂ forming a Ge-rich polycrystalline layer. As for wet oxidation, Ge was incorporated into the oxide, forming a layer of mixed oxide, SixGe₁₋xOy. Formation of nanocrystalline Ge was observed when the layer of SixGe₁₋xOy was annealed in a N₂ ambient. We have fabricated a metal-insulator-semiconductor structure with nanocrystalline Ge embedded within the insulator layer to study its feasibility as a memory device. / Singapore-MIT Alliance (SMA)

Thesis (M.C.E.)--University of Delaware, 2006. / Principal faculty advisor: James Kolodzey, Dept. of Electrical and Computer Engineering. Includes bibliographical references.

Thesis (Ph. D.)--University of Delaware, 2006. / Principal faculty advisor: Andrew V. Teplyakov, Dept. of Chemistry & Biochemistry and Raul F. Lobo, Dept. of Chemical Engineering. Includes bibliographical references.

Thesis (M.E.E.)--University of Delaware, 2006. / Principal faculty advisor: James Kolodzey, Dept. of Electrical and Computer Engineering. Includes bibliographical references.

Thesis (M.E.E.)--University of Delaware, 2006. / Principal faculty advisor: James Kolodzey, Dept. of Electrical and Computer Engineering. Includes bibliographical references.

The thesis provides the required knowledge base for establishing Laser Induced Stress Wave Thermometry (LISWT) as a viable alternative to current infrared technologies for temperature measurement up to 1000°C with ±1°C resolution. The need for a non-contact, high resolution thermal measurement methodology applicable to Rapid Thermal Processing (RTP) motivated the work. A stress wave propagation model was developed and a complex, temperature-dependent elasto-viscoplastic constitutive law was identified. A stagger-grid finite difference scheme was followed to approximate the solution field subject to temperature and plate thickness variations. Extensive numerical experiments were conducted to identify the proper time and spatial steps. A Gabor wavelet transform scheme was also employed for the extraction of wafer thermal and geometric information from exploring wave attenuation and dispersion. Researched results concluded that wave group velocity is a nonlinear function of temperature. Nonlinearity became more prominent at high temperatures and low frequencies. As such, for LISWT to achieve better thermal resolution at high temperatures, low frequency components of the induced stress wave should be exploited. The results also showed that the influence of temperature on attenuation is relatively small. It is not recommended to use attenuation for resolving temperature variation as small as several degrees Celsius. In addition to temperature, geometry also was found to have an impact on wave dispersion and attenuation. The results showed that the influence of thickness on wave velocity is significant, thus suggesting that for LISWT to achieve high temperature resolution, wafer thickness must be accurately calibrated in order to eliminate all possible errors introduced by thickness variation. The study established the basic framework for LISWT to be applicable to silicon wafer RTP at elevated temperatures. The model and methods developed for the course of the research can be easily adapted to account for other nondestructive evaluation applications involving the use of surface, plate or bulk waves for material characterization and thermal profiling.