EVIDENCE OF GAMMA-FREE OR BOUND-TO-DEEP ACCEPTOR CHARACTER OF THE Y-1.2 EV DEEP PHOTOLUMINESCENCE LINE IN N-TYPE GE-DOPED GAAS DERIVED FROMHIGH HYDROSTATIC-PRESSURE EXPERIMENTS IN DIAMOND-ANVIL CELL

The dependence of the energy position of the deep defect-related photo luminescence line Y-1.2 eV in Ge-doped GaAs on high hydrostatic pressu re is investigated using a Dunstan-type diamond anvil cell. The observ ation that the energy position of the line follows that of the GAMMA-c onduction band minimum in the 1 bar-30 kbar pressure range demonstrate s that the line has GAMMA-(free or shallow bound)-to-deep acceptor cha racter. This fact confirms the deep-acceptor character of the deep def ect, most likely a donor impurity-Ga vacancy complex, which contribute s to the Y-1.2 eV photoluminescence line.