Heterogeneous integration of Si photodiodes on silicon nitride for near-visible light detection

Abstract

Silicon nitride (SiN) is used extensively to complement the standard silicon photonics portfolio. However, thus far demonstrated light sources and detectors on SiN have predominantly focused on telecommunication wavelengths. Yet, to unlock the full potential of SiN, integrated photodetectors for wavelengths below 850 nm are essential to serve applications such as biosensing, imaging, and quantum photonics. Here, we report the first, to the best of our knowledge, microtransfer printed Si p–i–n photodiodes on a commercially available SiN platform to target wavelengths <850 nm. A novel heterogeneous integration process flow was developed to offer a high microtransfer printing yield. Moreover, these devices are fabricated with CMOS compatible and wafer-scale technology.

Monolithically integrated, broadband, high-efficiency silicon nitride-on-silicon waveguide photodetectors in a visible-light integrated photonics platform

“…The PDs reported here also have superior EQE and OE bandwidth compared to the heterogeneously integrated PDs in refs. 29 In summary, we demonstrated PDs monolithically integrated into a visible spectrum Si PIC platform. The SiN-on-Si PDs achieved broadband high-efficiency photon detection across the entire visible spectrum.…”

“…The PDs reported here also have superior EQE and OE bandwidth compared to the heterogeneously integrated PDs in refs. 29 and 28 . Si metal-semiconductor-metal (MSM) PDs integrated on SiN waveguides as in refs.…”

“…Thus far, on 100, 200, or 300-mm diameter Si wafers, visible/NIR photonic platforms with SiN 3 , 5 , 17 – 21 or Al 2 O 3 3 , 4 waveguides are usually passive, containing components such as gratings, power splitters, and interferometers, with waveguide phase-shifters tuned by the thermo-optic or strain-optic effect 5 , 22 – 24 . Post-fabrication processing and heterogeneous integration steps are used to incorporate liquid crystal phase-shifters 25 , lasers 26 , 27 , and photodetectors (PDs) 28 , 29 with SiN waveguides.…”

“…Thus far, on 100, 200, or 300-mm diameter Si wafers, visible/NIR photonic platforms with SiN 3,5,17-21 or Al 2 O 3 3,4 waveguides are usually passive, containing components such as gratings, power splitters, and interferometers, with waveguide phaseshifters tuned by the thermo-optic or strain-optic effect 5,[22][23][24] . Postfabrication processing and heterogeneous integration steps are used to incorporate liquid crystal phase-shifters 25 , lasers 26,27 , and photodetectors (PDs) 28,29 with SiN waveguides.On-chip optical-to-electrical conversion is an essential functionality in a PIC platform. In visible and NIR Si photonics, the Si substrate serves as a natural candidate for light absorption compatible with monolithic integration, circumventing heterogeneous integration that increases the fabrication complexity.…”

Coupling of Photonic Waveguides to Integrated Detectors Using 3D Inverse Tapering

“…We acknowledge financial support from the Autonomous Province of Trento, under the initiative "Quantum at Trento -Q@TN", projects Q-PIXPAD and CoSiQuP. [6] other (polysi) 0.15 0.8 [7] other (SOI) 0.22 0.44 [8] other (SOI) 0.22 0.32 [9] other (SOI) 0.25 0.74 [10] other (transf. SOI) 0.22 0.19 [11] other (SOI,λ =685nm) 0.25 0.83…”