ALUMINUM IMPURITY IN SIO2-SI SEMICONDUCTOR STRUCTURES

A neutron activation analysis was combined with a new method of layer- by-layer electrochemical etching of irradiated samples in a study of t he concentration and the distribution of aluminum impurities in silico n dioxide-silicon semiconductor structures. The concentration level of aluminum was found to be high and its distribution was extremely nonu niform in the bulk of the structure, with an accumulation mainly at th e phase boundaries of silicon dioxide and in surface layers of the sil icon plate. The effect of this impurity on the characteristics of semi conductor structures was analyzed.