SIMPLE MEASUREMENT OF 300 K ELECTRON-CAPTURE CROSS-SECTION FOR EL2 INGAAS

A simple experiment involving only the measurement of dark current I-d ark and 1.1 mu m photocurrent I-PC in semi-insulating (SI) GaAs allows an accurate determination of the electron capture cross section sigma (n) for the important defect EL2 in GaAs. For 45 SI GaAs samples, from 12 different boules, grown by three different techniques, we find tha t I-PC/I-dark=1.96+/-0.05 at 300 K. This relationship gives sigma(n)=1 .4+/-0.4X10(-16) cm(2), which is compared to previously estimated valu es. (C) 1996 American Institute of Physics.