Band gap determination of semiconductor powders via surface photovoltage spectroscopy

Surface photovoltage spectroscopy (SPS) is introduced as a powerful tool fo r band gap determination of semiconductor powders. The main advantage of SP S is that scattering and reflection do not interfere with the spectra. Ther efore, it does not suffer from the inherent limitations of transmission/ref lection based spectroscopies, most notably diffuse reflectance spectroscopy (DRS). The principles of the approach are presented and its usefulness is demonstrated by comparing it with DRS for band gap determination of GaAs, I nP, CdTe, CdSe, and CdS semiconductor powders. (C) 1999 American Institute of Physics. [S0021-8979(99)01222-0].