3.2 kV AlGaN/GaN MIS-HEMTs employing RF sputtered Ga<inf>2</inf>O<inf>3</inf> films

Abstract

AlGaN/GaN metal insulator semiconductor high electron mobility transistors (MIS-HEMTs) employing rf sputtered 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> have been proposed and fabricated. A very high breakdown voltage exceeding 3200 V and a low drain leakage current of 230 nA/mm at gate-drain distance (L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">GD</sub> ) of 40 μm was achieved without any sacrificing DC output characteristics while those of the unpassivated HEMT were 350 V and 134 μA/mm. The breakdown voltage of the 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> passivated HEMT was increased with increase of L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">GD</sub> because the injected electrons into the deep traps in 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> effectively extended the depletion region between the gate and the drain. And the injected electrons into deep traps have high activation energy for de-trapping so that the reverse blocking characteristics of the 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> passivated HEMT were considerable improved.