Thermally stimulated current measurements in N-type LEC GaP

Thermally stimulated current measurements have “been performed on n-type LEC GaP substrates. Nine deep donor states with energy level ranging from 0.27eV to 0.90eV have been observed. The most prominent peak at O.36eV has been associated with the incorporation of common donors Te, Se and S and it is found that the concentration of this 0.36eV trap increases as the square of the net doping concentration (N_D-N_A). Association of this O.36eV trap with the commonly observed 1.72eV luminescence band and the S-pits in LEC crystals is discussed.