以電子迴旋共振化學氣相沉積 (electron cyclotron resonance chemical vapor deposition, ECRCVD)成長a-Si:H薄膜，具有低溫成膜性質及沉積速率較快等優勢，將有效降低製作元件成本。然而，a-Si:H薄膜為矽氫所組成，其結構相對於結晶矽鬆散，且矽氫鍵結斷裂形成缺陷，易發生光衰退效應，當a-Si:H薄膜結構有序性增加，對於光照衰退有較佳之抵抗能力、缺陷密度降低及載子移動率增加，故使薄膜結構有序性增加有氫氣稀釋法(hydrogen dilution method)直接成長為微晶結構及退火熱處理法(thermal annealing method)促使非晶相形成結晶相薄膜等方式，以提升薄膜太陽能電池之效率。
　　本研究將針對以ECRCVD成長之a-Si:H薄膜，利用管型爐進行熱退火處理，並由Raman、XRD、SEM、TEM及XPS儀器分析並觀察晶相、晶粒大小與方向、微結構及Si原子鍵結形態。探討熱處理之薄膜結晶化過程，發現結晶時間隨溫度上升而減少，進而控制退火溫度與時間以獲得薄膜之不同結晶率與晶粒尺寸，由實驗結果得知，ECRCVD薄膜之結晶率可達至~80 %，晶粒大小約為~17 nm。
　　利用固態結晶法(solid phase crystallization, SPC)機制，描述晶粒成核與成長情況，並以熱力學模型得出結晶率與退火時間關係，探討a-Si:H薄膜熱處理結晶化過程，其包含四種步驟：薄膜之incubation、晶粒成核、晶粒成長及完全結晶，發現結晶時間隨溫度上升而減少。由成核成長理論分別求得熱力學參數，其薄膜之incubation time 活化能為3.51 0.09 eV；成長速率活化能為2.54 0.13 eV。此外，將a-Si:H薄膜置於氧氣氛中加熱，由於Si懸鍵與O原子易產生鍵結反應，並觀察退火溫度與時間對a-Si:H薄膜之氧化程度，探討a-Si:H薄膜結晶率之提升效應與氧化機制。

Hydrogenated amorphous silicon (a-Si:H) thin films were deposited on pre-oxidized Si wafers at low-temperature by electron cyclotron resonance chemical vapor deposition (ECRCVD). The furnace annealing treatment by solid-phase crystallization (SPC) method were applied to the as-grown films in nitrogen or oxygen atmosphere, and the temperature range for variable times was from 612℃ to 675℃.
The crystallization and grain growth behaviors of the annealed films were investigated by Raman spectroscopy and X-ray diffraction (XRD). The crystalline fraction of annealed films can reach ~ 80% , and a grain size up to 17 nm could be obtained from the FA treatment at high temperature. The surface morphologies and microstructure of annealed films were observed by scanning electron microscope (SEM) and transmission electron microscope (TEM).
The evolution of crystallization with nucleation and grain growth process for annealed films was described by classical thermal kinetics. The activation energy of ECRCVD film in incubation time and grain growth were 3.51 0.09 eV and 2.54 0.13 eV, respectively. Moreover, the a-Si:H films were oxidized at lower temperature in oxygen atmosphere. The chemical states of silicon of thermal oxidized films were investigated for by X-ray photoelectron spectroscopy (XPS). The degree of oxidation for annealed films was dependent on annealing temperature and time. The crystalline fraction of annealed films in oxygen atmosphere was higher than in nitrogen atmosphere due to the amorphous phase was oxidized in Raman spectra.

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