Photocapacitance measurements on deep levels in GaAs under hydrostatic pressure

Abstract

Transitions identified with emission of electrons and holes from Cr²⁺ and O centres in GaAs have been followed as a function of hydrostatic pressure up to 8 kbar. The pressure coefficients of the complementary energy sums are 4.7+or-1.5 and 3.0+or-1.5 MeV kbar^-1 respectively. It is concluded that the dominant transitions to conduction band are weighted to the higher bands near X and L, rather than to low density of states minimum at Gamma , confirming earlier assignments of peaks obtained by rapid photocapacitance spectroscopy (White et al., J. Electron. Mater., vol.5, p.91 (1976) and J. Appl. Phys., vol.47, p.3230 (1976)).