DETERMINATION OF FLAT-BAND POTENTIALS OF SILICON ELECTRODES IN HF BY MEANS OF AC RESISTANCE MEASUREMENTS

A new technique for determination of the flat-band potential, V-fb, ba sed on ac resistance measurements is presented. It is shown that imped ance measurements, performed with and without illumination at a single , relatively high frequency of 75 kHz can yield information about the semiconductor space charge layer and the position of the energy levels of a semiconductor/electrolyte system. The method was successfully te sted with n-type and p-type Si samples of different resistivities, use d as working electrodes in HF containing electrolyte solutions. The re sults obtained were compared with the flat-band potential data for sil icon as known from the literature. (C) 1998 Elsevier Science S.A. All rights reserved.