High-Resolution Time-Resolved Carrier Lifetime and Photoluminescence Mapping of 4H-SiC Epilayers

Abstract:

We present a comparison between time-resolved carrier lifetime mappings of several samples and integrated near band edge intensity photoluminescence mappings using a pulsed laser. High-injection conditions and as-grown material are used, which generally allow for the assumption of a single exponential decay. The photoluminescence intensity under these circumstances is proportional to the carrier lifetime and the mappings can be used to detect lifetime-influencing defects in epilayers and give an estimate of the carrier lifetime variation over the wafer. Several examples for the defect detection capability of the system are given.

• Periodical: Materials Science Forum (Volumes 717-720)
• Pages: 293-296
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.717-720.293
• Online since: May 2012
• Authors: I.D. Booker, Jawad Hassan, Erik Janzén, Peder Bergman
• Keywords: Carrier Lifetime, Epitaxial Defects, Full Wafer Mapping, Photoluminescence (PL)

References

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