THE PHOTO C-V CHARACTERISTICS OF THE AU GEO2/GE MOS CAPACITOR/

The UV illumination effect on the C - V curves was measured for the Au /GeO2/Ge MOS capacitor. The high frequency C - V curves shifted in pos itive direcrtion with UV light along the gate bias V axis and the indu ced charge at the Ge surface Q'(s) was estimated from the voltage shif t. The charge Q'(s) is induced by the electrons which are photoemitted into and trapped in GeO2. The photo-induced charge Q'(s) appears at h v = 2.0 eV, goes through a maximum at hv = 3.7 eV, and decreases abrup tly thereafter. It was assumed that the increase in Q'(s) is caused by the internal photoemission and its decrease is due to the recombinati on with holes which arise from electron-hole pair generation in GeO2. Based on these results, the mechanism of photoconduction on the surfac e oxidized Ge film is discussed.