Monolithically Integrated <b>μ</b>LEDs/HEMTs Microdisplay on a Single Chip by a Direct Epitaxial Approach
Yuefei Cai, Chenqi Zhu, Wei Zhong, Peng Feng, Sheng Jiang, Tao Wang
Abstract
Abstract There is a significantly increasing demand on developing a microLED ( μ LED) based microdisplay which may be the only display system that can meet the requirements for augmented reality/virtual reality systems, helmet mounted displays, and head‐up displays. However, a number of fundamental challenges which cannot be met by any existing technologies need to be overcome before such a microdisplay with satisfied performance becomes possible. In this paper, a different type of integration concept using an epitaxial approach is proposed, aiming to monolithically integrate μ LEDs and high electron mobility transistors (HEMTs) on a single chip. This concept can be potentially realized by using a selective epitaxial overgrowth method on a predefined HEMT template featuring microhole masks. Finally, the proposed epitaxial integration concept is translated into a prototype, demonstrating an 8 × 8 microLED microdisplay, where each μ LED is electrically driven by an individual HEMT which surrounds its respective μ LED via the gate bias of the HEMT.