多孔矽（Porous Silicon, PSi）因其奈米結構所帶來的量子侷限效應，展現出優異的光致發光（Photoluminescence, PL）特性，成為發展矽基光源的重要材料。因此，如何降低成本製作出有發光穩定度的多孔矽的技術便成為一關鍵課題。 為提升其發光效率與穩定性，本研究採用低溫濕式製程技術，對多孔矽進行各種表面修飾處理，探討不同溶液對其奈米晶粒尺寸與表面化學態的影響，進一步分析對光致發光波長藍移及發光強度提升之效果，並深入探討各種低溫條件下溶液混合的處理機制。 實驗結果顯示，於低溫條件下使用雙氧水與氨水混合溶液處理可獲得最佳發光效果。PL光譜測得的結果顯示，其發光波長明顯藍移至黃光區域，且發光強度大幅提升；X射線光電子能譜（XPS）分析亦證實表面形成緻密氧化層，對應於多孔矽表面經氧化改質後所形成的保護層，有效穩定奈米晶粒結構並強化量子侷限效應；透過穿透式電子顯微鏡（TEM）觀察，可清晰辨識矽奈米晶粒之存在，進一步佐證量子侷限效應之發揮。 本研究最終目標為開發具高穩定性與高發光效率之多孔矽材料，期望能促進其於矽光子元件在光通訊與生醫感測等應用領域之發展。;Porous silicon (PSi), due to its nanostructure-induced quantum confinement effect, exhibits excellent photoluminescence (PL) properties and is considered a promising material for the development of silicon-based light sources. A key challenge lies in fabricating PSi with high emission stability through cost-effective processes.
To enhance PL efficiency and stability, this study adopts a low-temperature wet chemical process to apply various surface modifications to PSi. The research focuses on examining the effects of different chemical solutions on the nanocrystal size and surface chemical states of PSi, and further analyzing their influence on PL blue shift and emission intensity enhancement. In particular, the synergistic effects of solution mixtures under low-temperature conditions are investigated. Experimental results indicate that a mixed solution of hydrogen peroxide and ammonia at low temperature yields the most favorable outcome. PL measurements reveal a significant blue shift in the emission wavelength toward the yellow region,accompanied by a notable increase in intensity. X-ray photoelectron spectroscopy (XPS) confirms the formation of a dense surface oxide layer, corresponding to a protective coating that stabilizes the PSi nanostructure and enhances the quantum confinement effect. Transmission electron microscopy (TEM) further verifies the presence of silicon nanocrystals, reinforcing the role of quantum confinement.
The ultimate goal of this research is to develop porous silicon materials with high stability and strong luminescence, paving the way for their application in silicon photonic devices, particularly in optical communication and biomedical sensing fields.
