Title :
Back contact effects in thin-film photovoltaics
Author :
Roussillon, Y. ; Karpov, V.G. ; Shvydka, Diana ; Drayton, J. ; Compaan, A.D.
Author_Institution :
Dept. of Phys. & Astron., Toledo Univ., OH, USA
Abstract :
The Schottky barrier formed at the back contact is shown to either act as the commonly accepted back-diode or as a reach-through diode. Rare local spots with low back barrier transparency and/or weak main junctions shunt the photocurrent, thus decreasing the measured open-circuit voltage and device efficiency. This phenomenon was observed experimentally in the case of thin-film CdTe photovoltaics. Combining a proper main junction and an adequate back-contact results in 13% efficient CdTe solar cell without intentional copper doping.
Keywords :
II-VI semiconductors; Schottky barriers; Schottky diodes; cadmium compounds; photoconductivity; semiconductor thin films; solar cells; thin film devices; CdTe; CdTe solar cell; Schottky barrier; back barrier transparency; back contact effects; back-diode; copper doping; device efficiency; local spots; open-circuit voltage; photocurrent; reach-through diode; thin-film CdTe photovoltaics; thin-film photovoltaics; weak main junctions; Astronomy; Charge carriers; Photoconductivity; Photovoltaic cells; Physics; Schottky barriers; Schottky diodes; Semiconductor diodes; Transistors; Voltage;
Conference_Titel :
Photovoltaic Specialists Conference, 2005. Conference Record of the Thirty-first IEEE
Print_ISBN :
0-7803-8707-4
DOI :
10.1109/PVSC.2005.1488164
