掺杂B(CH)_3的P型a-SiC:H层及a-Si:H电池的P/I界面研究

Study of B(CH_3)_3 Doped a-SiC and P/I Interface of a-Si:H Solar Cells

研究了衬底温度、反应气体流量等工艺条件对掺杂B（CH3）3（TMB）的P型氢化非晶硅碳（a-SiC：H）窗口材料性能的影响，获得了电导率达到8．97×10^-7／cm、光学带隙大于2．0eV的P型a-SiC：H窗口材料。研究了单结电池P型a-SiC：H窗口层的CH4流量与P、I层制备温度三者间的匹配关系。结果表明，随着衬底温度的提高，需要更多的CH4流量以增大P型窗口层的带隙B和电池的短路电流密度Jsc；沉积系统中，P型窗口层的温度比本征吸收层高25-50℃时，电池性能较好。研究了3种类型的P／I缓冲层对单结电池性能的影响。大量实验表明，不掺B的C缓冲层适合于低温和小CH4流量情况使用；掺B的C缓冲层＋不掺B的C缓冲层适合于高温和大CH4流量情况使用；采用不掺B的C缓冲层的电池光稳定性高于采用B、C渐变缓冲层的电池。研究还表明，采用新型TMB作为P型窗口层掺杂剂的电池比传统采用B2H6作为P型窗口层掺杂剂的电池转换效率提高约1.0％。

The influences of the substrate temperature and gas flow rate on the performance of P-type a-Si：H materials doped with B（CH3 ）3 （TMB） were investigated. A high-quality window layer material with Eg wider than 2.0 eV and conductivity of 8.97×10^- 7 S/cm,has been fabricated. The results indicated that,with the increasing of the deposition temperature,the higher CH4 flow rate was needed to enlarge the band gap of P layer and Jsc of the solar cells,and the p layer temprature should be 25-50 degrees higher than that of I layer. Three P/I buffer layers were used to prepare the cells. The results indicated that the un-doped C-buffer layer is only suitable for lower CH4 flow rate and lower temperature, while the buffer layer with B and C buffer layer＋un-doped C-buffer layer is suitable for higher CH4 flow rate and higher temperature. The cells with un-doped C-buffer layer were more stable after light soaking than the cells with B and C-buffer layer. The efficiency of solar cells with P-layer doped with TMB is about absolute 1.0% higher than that with B2 H6.