Individually-addressable flip-chip AlInGaN micropixelated light emitting diode arrays with high cont
June 27th, 2008 | by admin |Individually-addressable flip-chip AlInGaN micropixelated light emitting diode arrays with high continuous and nanosecond output power.
Micropixelated blue (470 nm) and ultraviolet (370 nm) AlInGaN light emitting diode (\’micro-LED\’) arrays have been fabricated in flip-chip format with different pixel diameters (72 microm and 30 microm at, respectively, 100 and 278 pixels/mm(2)). Each micro-LED pixel can be individually-addressed and the devices possess a specially designed n-common contact incorporated to ensure uniform current injection and consequently uniform light emission across the array. The flip-chip micro-LEDs show, per pixel, high continuous output intensity of up to 0.55 microW/microm(2) (55 W/cm(2)) at an injection current density of 10 kA/cm(2) and can sustain continuous injection current densities of up to 12 kA/cm(2) before breakdown. We also demonstrate that nanosecond pulsed output operation of these devices with per pixel onaxis average peak intensity up to 2.9 microW/microm(2) (corresponding to energy of 45pJ per 22ns optical pulse) can be achieved. We investigate the pertinent performance characteristics of these arrays for micro-projection applications, including the prospect of integrated optical pumping of organic semiconductor lasers.
Zhang HX, Massoubre D, McKendry J, Gong Z, Guilhabert B, Griffin C, Gu E, Jessop PE, Girkin JM, Dawson MD.
Institute of Photonics, University of Strathclyde, Wolfson Centre, 106 Rottenrow, Glasgow G40NW, UK.