
78 Gallium Nitride (GaN): Physics, Devices, and Technology
Christy et al. [14] reported 1100 V of BV
gd
for devices (W
g
/L
gd
/L
g
= 15/20/1.5 µm) for
4-µm-thick buffer GaN with specic ON-resistance of 2.3 mΩ-cm
2
.
This is the highest BV
gd
achieved so far in the conventional single heterostructure
AlGaN/GaN HEMTs on 200-mm-diameter Si substrate. These values are almost
closer to the values achieved using 7.0-µm-thick buffer GaN on 100-mm-diameter
Si substrate by Selvaraj et al. [9]. However, Chen et al. [11] have reported only the
two-terminal buffer breakdown voltage of 1380 V with a total buffer thickness of 4.6
µm for the double heterostructure ...