Integration of high-speed GaAs metal-semiconductor-metal photodetectors by means of transfer printing for 850 nm wavelength photonic interposers

We propose and demonstrate the integration of 850 nm GaAs-based metal-semiconductor-metal (MSM) photodetectors (PDs) based on transfer printing for application in photonic interposers. Both devices that directly interface with a multimode optical fiber (with device dimensions of 70 mu m x 70 mu m) as well as devices that interface with a SiN waveguide layer through a grating coupler (with device dimensions of 30 mu m x 30 mu m) are demonstrated. The dark currents are measured to be 22 nA and 7.2 nA at 2 V bias for the larger and smaller PDs respectively. For 850 nm wavelength, the external responsivities are measured to be 0.117 A/W and 0.1 A/W at 2 V bias. 20 GHz bandwidth is measured. Open 40 Gb/s eye diagrams are realized. (C) 2018 Optical Society of America