Ultra-wideband integrated photonic devices on silicon platform: from visible to mid-IR

Abstract

Silicon photonics has gained great success mainly due to the promise of realizing compact devices in high volume through the low-cost foundry model. It is burgeoning from laboratory research into commercial production endeavors such as datacom and telecom. However, it is unsuitable for some emerging applications which require coverage across the visible or mid infrared (mid-IR) wavelength bands. It is desirable to introduce other wideband materials through heterogeneous integration, while keeping the integration compatible with wafer-scale fabrication processes on silicon substrates. We discuss the properties of silicon-family materials including silicon, silicon nitride, and silica, and other non-group IV materials such as metal oxide, tantalum pentoxide, lithium niobate, aluminum nitride, gallium nitride, barium titanate, piezoelectric lead zirconate titanate, and 2D materials. Typical examples of devices using these materials on silicon platform are provided. We then introduce a general fabrication method and low-loss process treatment for photonic devices on the silicon platform. From an applications viewpoint, we focus on three new areas requiring integration: sensing, optical comb generation, and quantum information processing. Finally, we conclude with perspectives on how new materials and integration methods can address previously unattainable wavelength bands while maintaining the advantages of silicon, thus showing great potential for future widespread applications.

Graphene‐Based Silicon Photonic Devices for Optical Interconnects

“…[63,70] The photonic damascene process enables the fabrication of very thick SiN films (0.8-1.75 μm) hosting waveguides with a propagation loss of less than 0.05 dB m −1 . [108] The optimized damascene process involves DUV lithography, dry etching, reflow, LPCVD SiN deposition, planarization, and SiO 2 cladding deposition, as illustrated in Figure 3(b). [109]…”

“…[60] This heterogeneous integration platform is capable of meeting the requirements of applications spanning from visible light to the mid-infrared bands. [108] Figure 4(a,b) illustrates the cross-sectional schemes of typical silicon photonics integration platforms, including a single-layer SiN and a double-layer SiN, respectively, [9,110] The first platform shown in Figure 4(a) is from AMF and features a single-layer SiN on top of a standard SOI. This platform successfully integrates SiN devices for large-scale light routing with SOI passive and active devices.…”

“…[ 60 ] This heterogeneous integration platform is capable of meeting the requirements of applications spanning from visible light to the mid‐infrared bands. [ 108 ]…”

Strong nonlinear-polarization in ZnMgO epitaxial thin-films with Li incorporation

“…Large χ (2) contributes to enhancing the response of second-harmonic generation (SHG) and increasing modulation efficiency [2]. χ (2) thin-films build up integrated optics and photonics, because they enable easy formation of waveguide with strong optical confinement, heteroepitaxial growth on mature microelectronic platform such as silicon, and large-area deposition with low-cost [3]. Various thin-films, including organic polymers with chromophores [4], ABO 3 type ferroelectrics materials such as BaTiO 3 [5] and LiNbO 3 -on-insulator [6], dielectrics such as AlN [7] and Ta 2 O 5 [8], semiconductor such as GaAs [9] and ZnO [10] have been widely studied for χ (2) process.…”

On‐Chip Arrayed Waveguide Grating Fabricated on Thin‐Film Lithium Niobate

“…[14,15] Although silicon has a transparent window covering the wavelength range from near-infrared to mid-infrared light, it has high absorption loss from the ultraviolet (UV) to visible. [16] Silicon nitride has a moderately high refractive index (%1.98@1550 nm) as well as low absorption loss (%0.0013 dB cm À1 ). [17,18] For applications requiring high-speed reconfiguration, the absence of electro-optic effect inhibits silicon-nitride-based AWG from fast tuning of its operation wavelength.…”