Microwave-detected photoconductance decay

Author

Basore, Paul ; Hansen, Barry

Author_Institution

Sandia Nat. Lab., Albquerque, NM, USA

fYear

1990

fDate

21-25 May 1990

Firstpage

374

Abstract

Microwave-detected photoconductance decay provides a contactless measurement of the recombination lifetime of free carriers in semiconductors following a pulse of optical excitation. Several complications in interpreting the results obtained by this method have prevented its widespread acceptance. Detailed models are proposed and verified experimentally using a commercially available apparatus. The model adequately predicts the behavior of the microwave reflectance as a function of wafer conductivity and system configuration. A light-biased variation of the technique which makes it possible to characterize lifetimes as a function of excess carrier density is described. This capability makes it possible to measure the emitter saturation current density for diffusion in high-resistivity wafers, a valuable process control tool

Keywords

carrier lifetime; electrical conductivity measurement; electron-hole recombination; microwave reflectometry; minority carriers; photoconductivity; semiconductors; contactless measurement; emitter saturation current density; free carriers; high-resistivity wafers; microwave detected photoconductance decay; microwave reflectance; optical excitation; recombination lifetime; semiconductors; wafer conductivity; Microwave measurements; Optical pulses; Optical saturation; Photoconducting devices; Photoconductivity; Predictive models; Pulse measurements; Radiative recombination; Reflectivity; Semiconductor device modeling;

fLanguage

English

Publisher

ieee

Conference_Titel

Photovoltaic Specialists Conference, 1990., Conference Record of the Twenty First IEEE

Conference_Location

Kissimmee, FL

Type

conf

DOI

10.1109/PVSC.1990.111651

Filename

111651