Frequency and Area Dependence of High-K/Ge Mos Capacitors

This paper investigates the capacitance-voltage (C-V) measurements of Ge/Al2O3/ZrO2/TiN MOS capacitors at different frequencies for square devices with different side lengths (10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 100 μm). The results show that the series resistance corrected capacitance (CC) for accumulation region is dependent on frequency, devices substrate and area. CC increases at a faster pace when a lower frequency (1KHz) is used than at a higher frequency (1MHz). Substantial decrease of CC per unit area is reported in Ge/High-K in comparison to Si/High-K devices when device area is increased. This decrease is attributed to the large non-uniform interface defect density and high leakage current associated with Ge.