Thermal stability of dopant-hydrogen pairs in GaAs

Abstract

The thermal stability of dopant-hydrogen complexes in hydrogenated n- and p-type GaAs(1–2×1017 cm−3) has been determined by examining their reactivation kinetics in reverse-biased Schottky diodes. The reactivation process is first-order for all of the dopants, with thermal dissociation energies (ED) of 1.45±0.10 eV for SiAs acceptors, 1.25±0.05 eV for SiGa donors, 1.20±0.10 eV for SnGa donors, 1.25±0.10 eV for Zn acceptors, 1.35±0.05 eV for CAs acceptors, and 1.15±0.10 eV for Be acceptors. The dissociation frequencies (ν) are thermally activated of the form νD = ν0E−ED/kT, with the ν0 values in the range 1–5×1013 s−1. The results are consistent with much of the H being present as H+ in p-type material, and H− in n-type material.