Deep Levels in Non-Doped and Donor-Doped GaP

Four deep electron-trap levels were detected by DLTS from the non-doped and Te- or S-doped LEC-grown GaP. Some discussions are given regarding their origin. The density N t of these levels increased linearly with the net donor density N D for non-doped samples. N t was reduced by doping Te with N D ∼10 17 cm -3 , and then increased as N D 1.7 for N D >10 17 cm -3 .