Improved efficiency of a SiGe thin film solar cell structure using CNT charge collector layer

In this study, a SiGe (Si(۱-X) GeX x=۰.۱) thin film solar cell structure based on the carbon nanotube charge collector (CNT) is investigated. The addition of the carbon nanotube layer to cell structure has been proven to change aspects of its physical characteristics, specifically the efficiency of the solar cell. This means that CNT can have a significant impact on structure. The efficiency of suggested structure is ۲۷.۷۲%, which is higher than conventional structures without CNT layer. We optimize this structure by varying the cell layers thickness and calculating the ratio of the top metal contact to the total cell width. Furthermore, the performance of this cell is considering in present of two types of CNT layers with sheet resistances of ۱۲۸Ω/□ and ۷۶Ω/□. According to numerical simulation CNT layer with ۱۲۸ Ω/□ sheet resistance has better performance parameters. Finally, the number of metal electrodes above the cell is optimized due to the shading effect and we show that the contact distance in the presence of CNT layer can be increased up to ۱۰۰۰ μm. The cell efficiency after this optimization reaches ۳۰.۹%.

Keywords:

SiGe , thin film Solar cell , Carbon nanotube (CNT) , Optimization