Shinichi Hara

Surface charges in a ZnO-B/sub 2/O/sub 3/-SiO/sub 2/ glass/silicon system

ZnO-B/sub 2/O/sub 3/-SiO/sub 2/ glasses of different compositions were prepared and the surface charges in glass/silicon systems in which these glasses were used, were studied by measuring the capacitance-voltage curves of metal-glass-silicon capacitors. The effects of glass film thickness, glass composition, and conductivity (n-and p-types) of of silicon substrates on surface charges in glass/silicon systems were investigated. The surface charge density of n-type silicon changed in the negative direction with increasing glass film thickness and became constant with a thickness of more than 2 ..mu..m. The more negative the glass charge, the lower was its surface-state density. The surface-charge density of glass coated n-type and p-type silicon substrates were found to be linearly related. The surface charge density of mixed glasses with different surface charge density was also investigated.

Surface Charges in a Zinc‐Borosilicate Glass/Silicon System

Surface charges in a zinc‐borosilicate glass/silicon system were studied by measuring capacitance‐voltage curves of metal‐glass‐silicon capacitors at various temperatures. The capacitance‐voltage curves change remarkably with measurement frequency and temperature. The density of positive fixed charge decreases significantly with increasing glass firing temperature and also when nitrogen gas is added to the oxygen firing atmosphere. On the other hand, the density of the surface state is about and insensitive to glass firing conditions. The surface charge is positive for n‐type silicon and negative for p‐type silicon when the Fermi level is near the intrinsic energy level. The surface charges are reversed, however, when the Fermi level is near the bandedge.