Monolithically integrated InAs/InGaAs quantum dot photodetectors on silicon substrates

Yating Wan,Justin Norman,Di Liang,Daehwan Jung,Mj Kennedy,Ruilin Chao,Arthur C Gossard,John E Bowers,Kei May Lau,Qiang Li,Jin-Wei Shi,Chen Shang,Chong Zhang,Zeyu Zhang

doi:10.1364/oe.25.027715

Abstract

We report InAs/InGaAs quantum dot (QD) waveguide photodetectors (PD) monolithically grown on silicon substrates. A high-crystalline quality GaAs-on-Si template was achieved by aspect ratio trapping together with the combined effects of cyclic thermal annealing and strain-balancing layer stacks. An ultra-low dark current of 0.8 nA and an internal responsivity of 0.9 A/W were measured in the O band. We also report, to the best of our knowledge, the first characterization of high-speed performance and the first demonstration of the on-chip photodetection for this QD-on-silicon system. The monolithically integrated waveguide PD shares the same platform as the previously demonstrated micro-ring lasers and can thus be integrated with laser sources for power monitors or amplifiers for pre-amplified receivers.

Highlights

The established silicon (Si) complementary metal-oxide semiconductor (CMOS) technology infrastructure can be leveraged to revolutionize on-chip integration of photonics and electronics with low-cost and high-volume manufacturing capabilities [1,2,3,4,5,6]
We report a monolithically integrated InAs/InGaAs quantum dot (QD) waveguide PD and a proof of principle demonstration of laser photodetector integration via free-space coupling developed on the same material platform
Pd/Ti/Pd/Au and Pd/Ge/Au layer stacks were deposited by E-beam evaporation to form the p and n ohmic contacts. 12-nm atomic-layer deposited (ALD) Al2O3 together with a 1 μm-thick sputtered SiO2 layer were used as the passivation layer to help suppress the dark current

Summary

Introduction

The established silicon (Si) complementary metal-oxide semiconductor (CMOS) technology infrastructure can be leveraged to revolutionize on-chip integration of photonics and electronics with low-cost and high-volume manufacturing capabilities [1,2,3,4,5,6]. For optoelectronic integrated circuits (OEIC), it is essential to achieve on-chip detection of light with a photodetector (PD) [7,8]. To circumvent the inefficient light absorption from Si and achieve wafer-scale integration of PDs on a Si platform, typically additional material compatible with group IV semiconductor processing is required. Integration of III-V materials on Si represents a promising alternative to leverage the economies of scale of Si while maintaining the highest efficiency and yield [13,14]

Methods

Conclusion