THEORETICAL-STUDY OF THE GRADUAL CHEMICAL-TRANSITION AT THE SI-SIO2 INTERFACE .2. ELECTRONIC DENSITY OF STATES CALCULATIONS

Calculations of the electronic density of states at the Si-SiO//2 interface performed with the help of the cluster-Bethe-lattice method are presented. A cluster is constructed which realizes the semiconductor-insulator transition between a Bethe lattice of Si atoms and an SiO//2 Bethe lattice within three atomic SiO//x layers with average x values of 0. 33, 1. 17, and 1. 67. The resulting densities of states are compared with corresponding results for bulk SiO//x and the static effective charges of all the cluster atoms are calculated. The results are presented and discussed.