1.85 kV Breakdown Voltage in Lateral Field-Plated Ga2O3 MOSFETs

Abstract

A 400-nm thick composite field plate oxide, with a combination of atomic layer deposited and plasma enhanced chemical vapor deposited SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> layers, is used to enhance the breakdown voltage of spin-on-glass source/drain doped lateral Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> MOSFET. Three terminal breakdown voltage measured in Fluorinert ambient reaches 1850 V for a L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">gd</sub> = 20 μm device. This is the first report of lateral Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> MOSFET with more than 1.8 kV breakdown voltage. For a device with L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">gd</sub> = 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.