Solar Cell Device Physics, 2nd Edition

APPENDIX C

Shockley-Read-Hall (Gap-state–assisted) Recombination

This appendix derives the Shockley-Read-Hall (S-R-H) gap-state–assisted recombination-generation mathematical model.1, 2 The derivation begins with Figure C.1, which depicts gap states at some energy ET. These states are being used by carriers to provide a recombination-generation path between the conduction band and the valence band. We write the conduction-band electron traffic (electrons per volume per time) following path₁ to these states of number NT per volume as path₁ = , where v is the electron thermal velocity, σn is the capture cross-section of these gap states for electrons ...