Title :
Improvement of the open-circuit voltage of Cu2ZnSnS4 cells using a two-layered process
Author :
Tajima, Shinya ; Itoh, Takayuki ; Hazama, Hirofumi ; Ohishi, Kiyoshi ; Asahi, Ryoji
Author_Institution :
Toyota Central R&D Labs., Inc., Nagakute, Japan
Abstract :
In Cu2ZnSnS4 (CZTS) photovoltaic cells, a low open-circuit voltage (VOC) principally causes the low conversion efficiency. We investigated the deposition of a CZTS layer using two-layered process to improve the VOC of the CZTS cells. In this process, the first CZTS layers near Mo electrode was composed of high Cu content and the second layer near surface was composed of low Cu content. The two-layered process improved the Voc of the CZTS cells, and the value increased from 0.66 to 0.78 V. Finally, the best CZTS cell showed a conversion efficiency of 8.8%.
Keywords :
copper compounds; electrochemical electrodes; solar cells; tin compounds; zinc compounds; CZTS photovoltaic cells; Cu2ZnSnS4; efficiency 8.8 percent; low conversion efficiency; low open-circuit voltage; molybdenum electrode; second layer near surface; solar cells; two-layered process; Indexes; RNA; Read only memory; Tin; CZTS; carrier concentration; chalcogenide; composition gradient; open-circuit voltage;
Conference_Titel :
Photovoltaic Specialist Conference (PVSC), 2014 IEEE 40th
Conference_Location :
Denver, CO
DOI :
10.1109/PVSC.2014.6924951
