1200 V Multi-Channel Power Devices with 2.8 Ω•mm ON-Resistance

Here we report novel multi-channel AlGaN/GaN MOSHEMTs with high breakdown voltage (V
BR
) and low ON-resistance (R
ON
). The multi-channel structure was judiciously designed to yield a small sheet resistance (R
s
) of 80 Ω/sq using only four 2DEG channels, resulting in an effective resistivity (ρ
eff
) of only 1.1 mΩ•mm. The major limitation of high-conductivity multi-channel devices is their limited V
BR
. This work shows that while conventional field plates (FPs) are not suited to increase V
BR
in high-conductivity multi-channels, slanted tri-gates offer better electric field management inside the device. With a gate-to-drain separation (L
GD
) of 15 µm, the device presented a low R
ON
of 2.8 Ω•mm (considering the full width of the device (w
device
)) and a high V
BR
of 1230 V, rendering a small specific R
ON
(R
ON,SP
) of 0.47 mΩ•cm
²
and an excellent figure-of-merit of 3.2 GW/cm
²
. This work also shows the feasibility of E-mode multi-channel MOSHEMTs with a threshold voltage (V
TH
) of +0.9 V at 1 µA/mm by tuning the tri-gate geometry. These results significantly outperform conventional single-channel devices and demonstrate the enormous potential of multi-channel power devices.