鈍化層於高效率混合式 矽異質接面太陽能電池之應用

Abstract

在本論文中，我們希望可以將本實驗室原有的混合式矽基板異質接面太陽能電池提高效率，所以選擇了氧化鋁以及二氧化鈦膠體來當作表面鈍化層來將低矽基板表面的缺陷以及懸浮鍵進而提高元件的光電轉換效率。首先是在元件的正面，我們選擇用超薄氧化鋁來鈍化矽奈米線的表面，成功地減少元件漏電流使開路電壓上升進而提升元件的光電轉換效率，在最好的情況下能從11.8 % 提升到12.4 %，其中開路電壓從535 mV提升至544 mV。 另外我們也選擇在矽基板的背表面去做鈍化處理，其中氧化鋁也可以成功將矽基板的表面附合速率減至100 cm/s以內，在經過400度退火之後。在元件方面，雖然我們無法用最好的鈍化條件去做出元件，但是也可以看出氧化鋁在背表面的鈍化效果能可以將元件的光電轉換效率從10.95 %提升至12.09 % 的高效率。在最後一個部分，是為了要邁向全水溶液製程，所以我們選擇了一個表面鈍化效果也不錯的二氧化鈦膠體，在只使用旋塗機就可以將二氧化鈦膠體成功加入元件中，也有能使元件的光電轉換效率有不錯的提升，從10.95% 提升至11.93%。

In this study, we purpose to enhance the power efficiency of hybrid silicon heterojunction solar cell. There are a lot of defect on the surface, which will limit the efficiency of the photovoltaic. Therefore we expect to put passivation layer on hybrid solar cell to reduce the surface defect. First, we use the ultrathin Al2O3 film to passivation the surface defect of the silicon nanowire which has large surface area. And we successfully improve the power efficiency from 11.8% to 12.4%. On the other hand, we measure the minority carrier lifetime of Al2O3 film on silicon substrate with QSSPC WCT-120. The surface recombination velocity (SRV) can be less than 100cm/s. And we also made the device with Al2O3 on rear surface of silicon substrate. The performance of the device can be enhanced from 10.95% to 11.09%. But our group’s goal forward the all solution hybrid silicon heterojunction solar cell. So we select TiO2 sol-gel solution to be the passivation layer of the hybrid solar cells, and the performance of the device can be increase from 10.95% to 11.93%