Impurity Parameters of Undoped and Zn-Doped p-Type GaP with Two Acceptor Levels Determined by Hall Measurements

Abstract

Hall measurements are performed in the temperature region 60 to 900 K on undoped and Zn‐doped p‐type GaP crystals grown by the SSD method. The p(T)‐curves of undoped samples show a small step caused by the presence of a medium deep acceptor with an activation energy (0.18 ± 0.02) eV beside the shallow acceptor carbon. Carbon is present in a low concentration in the Zn‐doped samples, too. The parameters (activation energy, concentrations) of the two acceptors in both types of samples are determined by an equation cubic in p.

Experimental arguments for the identity of EL6 with the 0.13 eV donor in bulk n-GaAs

“…The step in the Ig(n)-l/T curves at about room temperature indicates the existence of a deeper donor. By fitting these curves using a two-donor model [13], particularly the activation energy E,, and the concentration N,, of this medium-deep donor, but also the net concentration of the shallow donors ( N , -NA), are obtained (table 1). Although the total change in carrier concentration is small, this procedure yields the fit parameters with reasonable errors because a large temperature range including saturation is analysed.…”