AlGaN-Channel Gate Injection Transistor on Silicon Substrate With Adjustable 4–7-V Threshold Voltage and 1.3-kV Breakdown Voltage

We report on demonstrating the first Al
_0.05
Ga
_0.95
N-channel enhancement-mode (E-mode) p-GaN gate injection transistors (GITs) with an adjustable threshold voltage (
${V}_{\textsf {T}}$
) of 4–7-V by controlling the number of source-connected p-GaN bridges. To the best of our knowledge, it is the highest
${V}_{T}$
reported in p-GaN GITs. Comparing with GaN channel, the Al
_0.05
Ga
_0.95
N channel is used to minimize the polarization difference between channel layer and Al
_0.15
Ga
_0.85
N barrier layer and also increase the maximum affordable electric field of the channel so as to increase the
${V}_{T}$
and breakdown voltage. Combing with
$4.3~\mu \text{m}$
-thick buffer layer, E-mode GITs demonstrate an OFF-state breakdown voltage of 662, 770, 1034, and 1315 V at a gate-to-drain spacing of 5, 7, 11, and
$19~\mu \text{m}$
, respectively, showing the great promise of the AlGaN channel E-Mode GITs for future power electronics applications.