Premium
Modelling free‐carrier absorption in solar cells
Author(s) -
Clugston Donald A.,
Basore Paul A.
Publication year - 1997
Publication title -
progress in photovoltaics: research and applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.286
H-Index - 131
eISSN - 1099-159X
pISSN - 1062-7995
DOI - 10.1002/(sici)1099-159x(199707/08)5:4<229::aid-pip164>3.0.co;2-6
Subject(s) - free carrier absorption , absorption (acoustics) , free carrier , semiconductor , materials science , solar cell , optoelectronics , silicon , charge carrier density , carrier lifetime , wavelength , optics , doping , physics , composite material
Free‐carrier absorption can be a significant parasitic optical absorption process in solar cells. Although estimates of its influence have been made in the past, it has not previously been incorporated into a numerical semiconductor device simulator and studied in conjunction with other effects. A finite element model of free‐carrier absorption is presented that incorporates the dependency of the absorption coefficient on the carrier concentration profile, including the change in carrier density that occurs across a single finite element. This model has been implemented in the semiconductor modelling program PC1D for Windows, and used to simulate the effects of free‐carrier absorption on several types of silicon solar cells. It was found to have only a very small effect on cell efficiency, but can significantly affect the long‐wavelength spectral response, which has implications for device characterization. Empirical equations for the behaviour of free‐carrier absorption in a variety of materials are presented. © 1997 John Wiley & Sons, Ltd.