Photoluminescence Study of Undoped, Sn-Doped and S-Doped InP Single Crystals

Photoluminescence (PL) intensity distribution was measured at 4.2 K along the <011> direction across the wafer, to compare the etch-pit density (EPD) distribution for undoped, Sn-doped and S-doped InP. Exiciton, donor-acceptor and 1.06 eV peaks of the undoped InP have W-shapes corresponding to the EPD distribution. The 1.06 eV band seems to be related to In vacancies. The Sn-doped and the S-doped InP show broadened and shifted peaks to a higher energy side for near band-edge emissions. The PL intensity distributions and the EPD distributions are W-shaped for the Sn-doped and U-shaped for the S-doped InP, respectively.