A New Scheme for Monolithic Integration of III-V and Si for High Capacity Optical Communication and Networking

University Of California-San Diego, La Jolla CA

Investigators

Abstract

0307247 Yu In this research program, the PI will study a relatively unexplored scheme for monolithic integration of III-V compounds and silicon using a metallic layer, intended for relieving the thermal mismatch and to provide linear electrical connections across the bonding interface. Introducing a metallic layer interfacing between heterogeneous materials will open new device concepts due to the different nature of carrier transport. Bonding layers, which provide low resistance contact at the bottom of optoelectronic devices located on a silicon chip, can readily facilitate current injection, and can increase light output efficiency by reflection. Furthermore, vertical electrical connections minimize the number of interconnections, and reduce thermal resistance to heat-sinks. The importance of combining light-emitting semiconductors with silicon integrated circuits on a single chip has long been recognized. This is because of the potentially tremendous improvement in speed, and efficiency of high-speed communications circuitry as a result of integration. Previous approaches towards monolithic integration such as epitaxial growth and wafer bonding face the difficulty of fundamental materials mismatch issues hindering full-scale wafer integration. This proposed research addresses the critical bonding issues of integrating dissimilar materials for enhanced performance of opto-electronic devices on Si chips. The investigation of compliant bonding for devices by studying a class of bonding reactions that involves transitions from liquid to solid to relieve thermal mismatch as bonding occurs. The reactions of the bonding system lead to low-resistance contact across the interface of the bonded pair. The bonding of GaAs and Si will be emphasized with exemplary devices as case studies. This program emphasizes fundamental materials and devices issues related to technology for very high capacity optical communication and networking. It also fosters collaboration with national and industrial laboratories, as well as training of students and modification of the graduate and the undergraduate curricula with research results.