1.85 kV Breakdown Voltage in Lateral Field-Plated Ga2O3 MOSFETs

A 400-nm thick composite field plate oxide, with a combination of atomic layer deposited and plasma enhanced chemical vapor deposited SiO ₂ layers, is used to enhance the breakdown voltage of spin-on-glass source/drain doped lateral Ga ₂ O ₃ MOSFET. Three terminal breakdown voltage measured in Fluorinert ambient reaches 1850 V for a L _gd = 20 μm device. This is the first report of lateral Ga ₂ O ₃ MOSFET with more than 1.8 kV breakdown voltage. For a device with L _gd = 1.8 μm, the average electric field strength is calculated to be 2.2 ± 0.2 MV/cm while the field simulation of the device shows a peak field of 3.4 MV/cm.