Micro-transfer printing of GaSb optoelectronics chips for mid-infrared silicon photonics integrated circuits

TL;DR

This paper demonstrates the first successful 3D integration of GaSb-based gain chips onto silicon photonics platforms using micro-transfer printing, advancing mid-infrared photonic integration for sensing applications.

Contribution

It introduces a novel micro-transfer printing method for GaSb chips and evaluates key fabrication features impacting device performance.

Findings

Successful transfer of GaSb chips onto silicon platform

Insights into fabrication factors affecting gain chip quality

Performance benchmarks for mid-IR photonic integration

Abstract

3D integration of GaSb-based gain chips on a silicon photonics platform using micro-transfer printing is demonstrated for the first time. The release process of GaSb coupons, and their transfer for the demonstration of hybrid GaSb/Silicon-photonics on-chip external cavity lasers is reported. A methodology to evaluate the key features of the gain chip coupons, namely the quality of the etched facets and the facet coating deposited using a wafer-level process, is introduced. The characterization provides insight into the fabrication factors limiting the performance of the gain coupons. The level of performance achieved for the transfer printing process offers a solid landmark for the development of photonics integration technology operating at the 2-3 $\mu$m wavelength range. This is instrumental for the deployment of mid-IR photonic integration technology in emerging applications related to gas and biomarker sensing.