We investigated the transport and photovoltaic properties of Cu(In 1-xGa x)Se 2 (CIGS) thin-film solar cells. The shunt-current-eliminated diode current could be obtained from the current-voltage characteristics by subtracting the parasitic shunt leakage current from the total current. The temperature dependence of the open-circuit voltage, extracted from the shunt-eliminated (total) current, suggested that the recombination activation energy is comparable to (much less than) the CIGS bandgap. The low-temperature characteristics of the diode ideality factor supported bulk-dominated recombination in the same cell. This suggests that shunt-current subtraction can provide the proper diode parameters of CIGS solar cells.
Bibliographical noteFunding Information:
This work was supported by the Converging Research Centre Program (2009-0093703) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science, and Technology (MEST), and MEST & Daegu Gyeongbuk Institute of Science and Technology (DGIST) ( 10-BD-0101 , Convergence Technology with New Renewable Energy and Intelligent Robot).
- CIGS thin film
- Open-circuit voltage
- Recombination activation energy
- Shunt current
- Solar cells