Table 4.

Advantages and disadvantages of the three main normally-off GaN HEMT solutions in terms of processing and performances: “cascode” configuration, p-GaN gate and recessed gate hybrid MISHEMT.

Normally-Off Design	Advantages	Disadvantages
Cascode	-Use of standard MOSFET gate driver -Stable Vth > 0 of the Si MOSFET	-Package complexity -Optimization of Si MOSFFET needed in each application -Not suitable for low voltage (<600 V) and high frequency (>1 MHz) applications
p-GaN gate	-Low resistance under the gate -No dielectric issues	-Optimization of p-GaN etching needed for low access resistance and better reliability -Limited positive gate voltage swing
Recessed gate hybrid MISHEMT	-Large forward breakdown -Standard device driving in applications	- Not suitable for low voltage application (100 V), due to the gate channel resistance -Critical impact of the gate module (interface and dielectric) on device performances (RON and reliability)