Abstract
TaYOx gate dielectric has been deposited on p-Ge by RF co-sputtering of Ta2O5 and Y2O3 targets. Charge trapping/detrapping behavior of Au/TaYOx/p-Ge MIS capacitors have been studied under DC and AC stressing of different amplitudes and dynamic voltage stresses in order to study the transient response and the degradation mechanism of the dielectric. The current transients observed during dynamic voltage stress have been interpreted in terms of the charging/discharging of Ge/TaYOx interface and bulk TaYOx traps. The change in Vfb and gate current during unipolar pulse voltage stressing shows that the main degradation takes place at low frequencies. Both types of trapping are observed under dynamic stressing both with the gate and substrate injections.