本論文研究利用奈米晶矽發光特性當作增益介質，藉由一維面射型分佈回饋式光學結構，形成一個微型共振腔，達到光強度放大及半高寬窄化的現象。首先利用自發輻射(A.S.E.)實驗量測了解奈米晶矽的增益係數，其淨增益係數為70cm-1。利用時域有限差分法(FDTD)模擬、布拉格繞射理論及耦合理論決定光柵週期為375nm，並希望設計為面射型，所以均分比(duty cycle)設計比例為0.7~0.8。製程部分，先利用電漿輔助化學氣相沉積系統，沉積富矽二氧化矽材料，並經過真空高溫退火1100度形成奈米晶矽，接著在鍍上透明導電電極以致於可利用電子束微影(E-beam)，在鍍上一層二氧化矽，並利用電子束微影(E-beam)及介電層反應離子蝕刻二氧化矽，完成分佈式回饋光柵結構。量測實驗結果，發現在不同光柵週期其對應的共振波長也不同與理論相符，也觀察到光放大及半高寬窄化。當光柵週期375nm時，光在波長578nm被放大到3.3倍且其半高寬從原先無分佈回饋式光學結構的半高寬200nm窄化到60nm。

Abstract
The thesis focuses on study of light emission of silicon nanocrystals (nc-Si) on one-dimeensional distributed feedback (DFB) structures. First of all, we fabricated SiO2/SiOx/SiO2/Si substrate rib waveguides and used variable-stripe-length (VSL) method to calibrate optical gain coefficient of silicon nanocrystals. The measured optical gain and loss coefficients of the waveguide are 70cm-1and 14cm-1, respectively. Next, Finite difference time domain (FDTD) method, Bragg diffraction theory and coupled mode theory were utilized to design the grating period, grating depth and duty cycle. The optimized grating period and duty cycle are 375nm and 0.7~0.8, respectively, according to the simulation results. To fabricate n-Si DFB, silicon-rich oxide deposited by PECVD was first annealed at 1100°C in vaccum to form nanocrystalline silicon on quart substrate. Then ITO and SiO2 were deposited on the device surface and the DFB structures were patterned by electron beam lithography and the following reactive ion etching. From the measurement results, we observed narrowed photoluminescence (PL) and enhanced peak intensity on the nc-Si DFB structures, showing significant stimulated emission of silicon nanocrystals around the resonant wavelength depending on the designed grating period. For the grating period of 375nm, the FWHM of PL was narrowed form 200nm to 60nm and the intensity was amplified by 3.3 times at the resonant wavelength of 578nm.

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