Monolithic integrated all-GaN-based µLED display by selective area regrowth
Yaying Liu, Zhaojun Liu, Kei May Lau
Abstract
This work demonstrates an all-GaN-based µLED display with monolithic integrated HEMT and µLED pixels using the selective area regrowth method. The monochrome µLED-HEMT display has a resolution of 20 × 20 and a pixel pitch of 80 µm. With the optimized regrowth pattern, the µLED-HEMT achieves a maximum light output power of 36.2 W/cm 2 and a peak EQE of 3.36%, mainly due to the improved crystal quality of regrown µLED. TMAH treatment and Al 2 O 3 surface passivation are also performed to minimize the impact of nonradiative recombination caused by the dry etching damage. With a custom-designed driving circuit board, images of “HKUST” are successfully shown on the µLED-HEMT display.
Topics & Concepts
High-electron-mobility transistorMaterials scienceOptoelectronicsPixelMonochromePassivationEtching (microfabrication)OpticsLight-emitting diodeGallium nitrideVoltageTransistorLayer (electronics)Electrical engineeringPhysicsNanotechnologyEngineeringGaN-based semiconductor devices and materialsGa2O3 and related materialsZnO doping and properties