Experimental evidence on removing copper and light-induced degradation from silicon by negative charge
- Department of Micro and Nanosciences, Aalto University, Tietotie 3, 02150 Espoo (Finland)
- SolarWorld Innovations GmbH, Berthelsdorfer Str. 111A, 09599 Freiberg (Germany)
In addition to boron and oxygen, copper is also known to cause light-induced degradation (LID) in silicon. We have demonstrated previously that LID can be prevented by depositing negative corona charge onto the wafer surfaces. Positively charged interstitial copper ions are proposed to diffuse to the negatively charged surface and consequently empty the bulk of copper. In this study, copper out-diffusion was confirmed by chemical analysis of the near surface region of negatively/positively charged silicon wafer. Furthermore, LID was permanently removed by etching the copper-rich surface layer after negative charge deposition. These results demonstrate that (i) copper can be effectively removed from the bulk by negative charge, (ii) under illumination copper forms a recombination active defect in the bulk of the wafer causing severe light induced degradation.
- OSTI ID:
- 22391905
- Journal Information:
- Applied Physics Letters, Vol. 105, Issue 18; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
Similar Records
Formation kinetics of copper-related light-induced degradation in crystalline silicon
Study of Passivation in the Gap Region Between Contacts of Interdigitated-Back-Contact Silicon Heterojunction Solar Cells: Simulation and Voltage-Modulated Laser-Beam-Induced-Current