The acoustic method of investigating the electrical carrier mobility of the real GaP:Te (110) surface$^*$

The acoustic method of investigating the carrier mobility in the near-surface region of a semiconductor is presented. In this method the transverse acoustoelectric voltage versus the absorbed surface acoustic wave power was measured to determine nondestructively the carrier mobilites. In the layered structure: piezoelectric - semiconductor, the majority and minority carrier mobilities can be determined basing on the field effect. Single GaP:Te(110) crystals have been investigated after various kinds pf surface treatment. The carrier mobility values range from 75 to 120 (cm$^{2}$/ V s). The results determined by means of the TAV method are in satisfactory agreement with the results obtained by Hall measurements