SBIR Phase II:Photopolymer-based Microelectronic Device Transfer Process

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase II project is to enable electronic products of great environmental benefit and social value which cannot be economically made today. Among these are three important product classes that can deliver on the promise of the connection of everyday devices via internet (Internet of Things) and their rapid computing power. First, wearable devices (such as smart watches, health monitors, or activity trackers) must be smaller, thinner (often flexible) and less power-hungry than current versions. Second, low-power, high resolution displays with high brightness are needed to visualize results, even in direct sunlight. Third, the decentralized computers which collect, manage and process large datasets require designs that can easily manage sensors, process information, and control devices to support smart cities, smart vehicles, smart homes, and smart applications. The primary focus of this project is to enable the next generation of advanced displays, capable of substantial energy savings coupled with greater visual appeal. Broadly, the results are critical for enabling the cost-effective manufacturing of each of the three product classes, which all suffer from fundamental challenges in chip manufacturing and require innovation in packaging and assembly to be commercially viable at scale.The proposed project is designed primarily to make better displays possible. There is a widespread desire to make displays with ultrasmall light-emitting diodes (LEDs), enabling better contrast and color, sunlight viewability, longer lifetimes, lower power consumption, and lower cost. To do so, currently unsolved chip fabrication obstacles must be overcome. The main impediment is a cost-effective approach to place such small LEDs at desired pixel positions with adequate precision. The objective of the project is to meet this need, using a unique non-contact photopolymer-based method which transfersless than 10 um die with +/- 2 um accuracy at many thousands of units per second with high yield. The research will involve systematic study of the parameters of the process, including polymer composition and characteristics, film characteristics, pre-transfer bonding process parameters (temperature, pressure and time), and optical system parameters. Yield will be measured statistically and improved. While demonstrating actual throughput requires full-scale production equipment, the feasibility of meeting industry required targets will be demonstrated to the extent possible on lab-scale equipment.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.