PFI-TT: Enabling Advanced High-Resolution Full-Color Displays with New Color Conversion Technologies

University Of Washington, Seattle WA

Investigators

Abstract

The broader impact/commercial potential of this Partnerships for Innovation - Technology Translation (PFI-TT) project is to enable augmented- and virtual-reality (AR/VR) technologies with high visual quality at lower costs. AR/VR technologies connect people with the digital world through immersive experiences, and present unbounded applications in many industries. However, these technologies face many obstacles, such as limitations in optical clarity and resolution. The display industry is in urgent need of new innovation that can achieve much higher resolutions than what existing technologies deliver. To this end, the industry is actively investing in micro-LED technology, where the pixel size nears an order of magnitude reduction from the current state of the art. Better resolution is desirable across the entire display industry, ranging from smartphones/watches to large panel displays, but micro-LEDs will benefit consumers most by transforming AR/VR. However, the manufacturing process of micro-LED displays is extremely time consuming and labor intensive, which leads to prohibitive costs, yields, and production times. The proposed technology is expected to profoundly reduce the cost of next generation displays for AR/VR and transition micro-LED displays from research to market. The proposed project advances a technology that will propel micro-LEDs through the manufacturing obstacles into mainstream displays. The technology combines a micro-patterning method and innovative light-emitting material, compatible with existing semiconductor manufacturing, and promises to significantly reduce the number of key steps in micro-LED manufacturing. Conventional micro-LED array fabrication requires processing each color of LED, blue, green, and red, on individual semiconductor wafers. These LEDs must then be separated and assembled on a display substrate through the manual and error-prone pick-and-place process. The proposed micro-color converter requires the creation of only a single blue micro-LED array, with no need to manage individual pieces. Color converters absorb light of higher energy and emit lower-energy light, and through patterning, select blue pixels can become green or red. The color converter utilizes metal-halide perovskite semiconductors, a cost-effective, solution-processible light-emitting material with outstanding optical properties. Like other organic materials, one significant challenge with perovskites is their incompatibility with standard photolithographic micro-patterning processes. The proposed technology bridges this gap by enabling micro-patterning of perovskites with many of the same photolithography tools already in production, while protecting the layers during fabrication thus maintaining the material’s high optical quality. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.