Interface States and Trapping Effects in Al_2O_3- and ZrO_2/InAIN/AIN/GaN Metal-Oxide-Semiconductor Heterostructures

摘要

We investigate Al_2O_3- and ZrO_2/InAIN/GaN metal-oxide-semiconductor heterostructures (MOS-H) using capacitance-time transients in the temperature range of 25-300 ℃. A deep-level transient spectroscopy based analysis revealed the maximum interface state density distributions D_(it)(E) up to 3×10~(13) and 1×10~(-13)eV~(-1)cm~(-2) for the Al_2O_3/InAIN and ZrO_2/InAIN interface, respectively. The integral densities of interface states correlate well with the trapping-related gate-lag effect in corresponding InAIN/GaN MOS high electron mobility transistors (HEMTs). This explains the strongly reduced lag effect in ZrO_2 MOS HEMTs. We assume hole trapping at oxide/InAIN interface to be a dominant effect responsible for the gate-lag effect in InAIN/GaN MOS HEMTs.