氫化非晶矽薄膜太陽能電池，因長時間能量產率佳、低照度條件下光電轉換效率高及材料價格便宜等優點，使其逐漸受到重視。在業界，常用PECVD成長氫化非晶矽太陽能電池，但因沉積速率慢、離子轟擊等缺點，故常使用沉積速率快且能大面積生長之ECR CVD，如能改善ECR CVD大面積下沉膜均勻性，則有利於應用於高效率、低光衰氫化非晶矽太陽能電池之量產。 本團隊改良單一主磁圈之ECR CVD，於製程盤面周圍裝上可調變磁場大小之內磁圈與外磁圈用以改善大面積沉膜均勻度。本研究目的在於調變ECR CVD之各磁圈電流大小，經由主磁圈、內磁圈及外磁圈相對應之磁場組態，輔以製程壓力、微波功率及基板溫度之參數改變，達到6吋氫化非晶矽沉膜面積高均勻性之目標。 研究發現當盤面內外磁場大小差異越大並且為磁場組態Cusp field、製程壓力越低、微波功率越高時，均勻性可由約20%改善至8%，而改變基板溫度時，對於大面積沉膜均勻度並不會有顯著的影響。最後我們將所有最佳均勻性參數組合，發現當主磁圈、下外磁圈及下內磁圈電流為36A、26A及36A，製程壓力1.5 mtorr，微波功率及基材溫度為2000W、350℃時，可以得到6%的高均勻度。 The crucial problem of solar cell is the energy-conversion efficiencies and the Manufacturing costs. The a-Si:H thin film solar is gradually interested in its great energy production rate for long time illumination，better conversion efficiency under low illumination and cheaper.in industry, a-Si:H is regularly deposited by PECVD. Because of the low deposition rate and ion bombard of PECVD, the Manufacturing costs will decrease if a-Si:H thin film solar cell were deposited by high deposition rate and large plasma source ECRCVD. To spread the application of ECRCVD to industry, it is necessary for developing large uniform plasma and is helpful for the quantity produces of high quality and low light-soaking degradation a-Si:H thin film solar cell. In our research group, we installed sub-magnetic (auxiliary) fields for inner and outer coils under ECR-CVD process chamber to improve the deposition uniformity of a-Si:H solar thin films. In this work, We adjusted process parameters like magnetic field distribution of deposition chamber, working pressure, microwave power substrate and temperature to improve the uniformity of a-Si:H thin film solar cell and succeeded in obtaining an excellent deposition uniformity of a-Si:H solar thin films over 150mm diameter on glass substrates. The thickness variations of 1% over 75 mm and 6% over 150 mm were achieved when (Main, Outer, Inner) coil current is (36A, 26A, 36A), working pressure is 1.5 mtorr, microwave power is 2000W, and substrate temperature is 350℃.
