In situ optical assessment of semi-insulating iron doped InP grown by liquid encapsulated Czochralski process

In semi-insulating, Fe doped InP, we demonstrate that infrared absorption t echnique provides quantitative measurements of Fe concentrations. We show t hat the quantum efficiency is reduced more than 70% in Fe doped samples, in comparison to undoped samples. Relative near band edge photoluminescence ( PL) intensity is antiproportional to Fe concentration. This can provide a c alibration method to transform scanning PL images to quantitative Fe distri butions. We demonstrate that infrared absorption mapping images Fe distribu tion in InP, in a similar way to EL2 imaging in GaAs. The images show that the slip-like defects decorated by Fe centers predominantly lie along [011] direction. (C) 1999 American Institute of Physics. [S0021-8979(99)04909-9] .