Iron distribution in silicon after solar cell processing: Synchrotron analysis and predictive modeling
The evolution during silicon solar cell processing of performance-limiting iron impurities is investigated with synchrotron-based x-ray fluorescence microscopy. We find that during industrial phosphorus diffusion, bulk precipitate dissolution is incomplete in wafers with high metal content, specific...
Main Authors: | , , , , , , , , |
---|---|
Other Authors: | |
Format: | Article |
Language: | en_US |
Published: |
American Institute of Physics (AIP)
2013
|
Online Access: | http://hdl.handle.net/1721.1/78005 https://orcid.org/0000-0002-4609-9312 https://orcid.org/0000-0001-8345-4937 |
Summary: | The evolution during silicon solar cell processing of performance-limiting iron impurities is investigated with synchrotron-based x-ray fluorescence microscopy. We find that during industrial phosphorus diffusion, bulk precipitate dissolution is incomplete in wafers with high metal content, specifically ingot border material. Postdiffusion low-temperature annealing is not found to alter appreciably the size or spatial distribution of FeSi[subscript 2] precipitates, although cell efficiency improves due to a decrease in iron interstitial concentration. Gettering simulations successfully model experiment results and suggest the efficacy of high- and low-temperature processing to reduce both precipitated and interstitial iron concentrations, respectively. |
---|