High Performance Monolithically Integrated GaN Driving VMOSFET on LED

Abstract

This letter reports the monolithic integration of GaN-based driving vertical metal–oxide–semiconductor field-effect transistor (VMOSFET) on light-emitting diode (LED) with high output current density and bright-ness. By selectively regrowing a simple p- and n-GaN bilayer on top of an LED wafer, the VMOSFET was realized with an n/p/n structure and intrinsically connected with the LED through the bottom conductive n-GaN layer. During the fabrication, a tetramethylammonium hydride wet etch technique was employed to smoothen the sidewall channel surface of the VMOSFET and to enhance its channel electron mobility, consequently achieving a high output current density exceeding 1.4 kA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . The integrated VMOSFET-LED exhibited a high light output power of 8.5 mW or 9.4 W/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> with a modulated injection current of 10 mA through the VMOSFET, showing a great potential of such integration scheme for a variety of smart-lighting applications.