Abstract
Metal impurities are known to hinder the performance of commercial Si-based solar cells by inducing bulk recombination, increasing leakage current, and causing direct shunting. Recently, a set of photoluminescence (PL) images of neighboring multicrystalline silicon wafers taken from a cell production line at different processing stages has been acquired. Both band-To-band PL and sub-bandgap PL (subPL) images showed various regions with different PL signal intensity. Interestingly, in several of these regions a reversal of the subPL intensity was observed right after the deposition of the antireflective coating. In this paper, we present the results of the synchrotron-based nano-X-ray fluorescence imaging performed in areas characterized by the subPL reversal to evaluate the possible role of metal decoration in this uncommon behavior. Furthermore, the acquisition of a statistically meaningful set of data for samples taken at different stages of the solar cell manufacturing allows us to shine a light on the precipitation and rediffusion mechanisms of metal impurities at these grain boundaries.
Original language | English (US) |
---|---|
Article number | 7742961 |
Pages (from-to) | 244-249 |
Number of pages | 6 |
Journal | IEEE Journal of Photovoltaics |
Volume | 7 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2017 |
Keywords
- Multicrystalline silicon (mc-Si)
- PL band reversal sub-band PL
- X-ray fluorescence
- photoluminescence (PL)
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering