1200 V GaN vertical fin power field-effect transistors

Abstract

We demonstrate record performance in a novel normally-off GaN vertical transistor with submicron finshaped channels. This vertical fin transistor only needs n-GaN layers, with no requirement for epitaxial regrowth or p-GaN layers. A specific on-resistance of 0.2 mfì-cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and a breakdown voltage over 1200 V have been demonstrated with extremely high ON current (over 25 kA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) and low OFF current at 1200 V (below 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-4</sup> A/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ), rendering an excellent Baliga's figure of merit up to 7.2 GW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . A threshold voltage of 1 V was achieved and was stable up to 150 °C. Large devices with high current up to 10 A and breakdown voltage over 800 V were also demonstrated. These results show the great potential of GaN vertical fin transistors for high-current and high-voltage power applications.