Analysis of DC/transient current and RTN behaviors related to traps in p-GaN gate HEMT

Trap-related transient characteristics and RTN in p-GaN gate HEMT were characterized, for the first time to our knowledge. Current conduction mechanism in DC I_G is explained based on proposed model. Hopping conduction mechanism is responsible for I_G at V_G <; 0. I_G at V_G > 0 seems to be controlled by thermionic emission and affected by the action of floating-base n(W)-p(p-GaN)-n(AlGaN/GaN) bipolar transistor. Transient current behavior is related to the DC conduction mechanism and could be explained by thermal emission and charge trapping in p-GaN and AlGaN layers. Measured transient behavior of gate capacitance corresponds to that of the transient currents. Hole trapping into the AlGaN layer and existence of percolation path in gate and drain currents are verified by analyzing RTNs in I_G and I_D. Trap position and activation energy regarding RTN are firstly extracted. RTN time constants are similar to those in I_G and I_D transient behavior.