Tunneling induced electron transfer in SiNx/AlGaN/GaN based metal–insulator–semiconductor structures

Tunneling induced electron transfer in SiNx/Al0.22Ga0.78N/GaN based metal–insulator–semiconductor (MIS) structures has been investigated by means of capacitance–voltage (C–V) measurements at various temperatures. Large clock-wise hysteresis window in C–V profiles indicates the injection of electrons from the two-dimensional electron gas (2DEG) channel to the SiNx layer. Depletion of the 2DEG at positive bias in the negative sweeping direction indicates that the charges injected have a long decay time, which was also observed in the recovery process of the capacitance after injection. The tunneling induced electron transfer effect in SiNx/Al0.22Ga0.78N/GaN based MIS structure opens up a way to design AlxGa1−xN/GaN based variable capacitors and memory devices.