Micro-transfer printing of InGaAs/InP avalanche photodiode on Si substrate

Abstract

We report on the fabrication and micro-transfer printing of InGaAs/InP avalanche photodiodes (APDs) onto silicon substrates. A process flow was developed to suspend the devices using semiconductor tethers. The developed process reduces the number of fabrication steps required compared to methods based on the use of photoresist tethers. Furthermore, our process is compatible with devices that may be susceptible to damage induced by the photoresist removal process. APDs were characterised in linear mode operation both before suspension and after printing. Despite the additional fabrication steps required to suspend the APD membranes and the physical nature of the micro-transfer printing process, the electrical characteristics of the devices were preserved. No degradation in the optical performance of the devices was measured. Our work represents the first demonstration of micro-transfer printing of InGaAs/InP avalanche photodiodes onto silicon substrates. The results highlight the viability of micro-transfer printing for effective heterogeneous integration of InGaAs/InP avalanche photodiodes with silicon photonic integrated circuits for optical and quantum communication and other light detection applications.