Combined dynamic and steady-state infrared camera based carrier lifetime imaging of silicon wafers

authored by: Klaus Ramspeck, Karsten Bothe, Jan Schmidt, Rolf Brendel
Abstract: We report on a calibration-free dynamic carrier lifetime imaging technique yielding spatially resolved carrier lifetime maps of silicon wafers within data acquisition times of seconds. Our approach is based on infrared lifetime mapping (ILM), which exploits the proportionality between the measured infrared emission and the free carrier density. Dynamic ILM determines the lifetime analytically from the signal ratio of infrared camera images recorded directly after turning on an excitation source and after steady-state conditions are established within the sample. We investigate the applicability of dynamic infrared lifetime mapping on silicon wafers with rough surfaces, study the impact of injection dependencies, and examine the technical requirements for measuring low lifetime values in the range of microseconds. While the dynamic ILM approach is suitable for lifetimes exceeding 10 μs, a combination with steady-state ILM is required to measure lifetime values in the range of 1 μs. The injection dependence does not hamper a correct determination of the carrier lifetime by the dynamic evaluation procedure.
External Organisation(s): Institute for Solar Energy Research (ISFH)
Schott AG
Type: Article
Journal: Journal of applied physics
Volume: 106
ISSN: 0021-8979
Publication date: 2009
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: General Physics and Astronomy
Electronic version(s): https://doi.org/10.1063/1.3261733 (Access: Closed)

BibTeX

@article{46856131bf2a4808be7d0e37f9bfe668,
title = "Combined dynamic and steady-state infrared camera based carrier lifetime imaging of silicon wafers",
abstract = "We report on a calibration-free dynamic carrier lifetime imaging technique yielding spatially resolved carrier lifetime maps of silicon wafers within data acquisition times of seconds. Our approach is based on infrared lifetime mapping (ILM), which exploits the proportionality between the measured infrared emission and the free carrier density. Dynamic ILM determines the lifetime analytically from the signal ratio of infrared camera images recorded directly after turning on an excitation source and after steady-state conditions are established within the sample. We investigate the applicability of dynamic infrared lifetime mapping on silicon wafers with rough surfaces, study the impact of injection dependencies, and examine the technical requirements for measuring low lifetime values in the range of microseconds. While the dynamic ILM approach is suitable for lifetimes exceeding 10 μs, a combination with steady-state ILM is required to measure lifetime values in the range of 1 μs. The injection dependence does not hamper a correct determination of the carrier lifetime by the dynamic evaluation procedure.",
author = "Klaus Ramspeck and Karsten Bothe and Jan Schmidt and Rolf Brendel",
note = "Funding Information: Thanks to Rafael Krain for temperature dependent QSSPC measurements. This work was supported by the German state of Lower Saxony.",
year = "2009",
doi = "10.1063/1.3261733",
language = "English",
volume = "106",
journal = "Journal of applied physics",
issn = "0021-8979",
publisher = "American Institute of Physics",
number = "11",
}