A modular fabrication process for thin-film lithium niobate modulators with silicon photonics. (1st April 2022)

• Record Type: Journal Article
• Authors: Mere, Viphretuo; Valdez, Forrest; Wang, Xiaoxi; Mookherjea, Shayan
• Is Part Of: JPhys photonics. Volume 4:Number 2(2022)
• Publication Date: 2022-04-01
• Subjects: electro-optic modulator -- lithium niobate -- high-speed modulation -- silicon photonics -- ring resonator -- photon-pair generation -- quantum sources; Photonics -- Periodicals; 621.365
• DOI: 10.1088/2515-7647/ac5e0b
• Languages: English
• ISSNs: 2515-7647

Abstract

Abstract: We report advancements in the fabrication of electro-optic Mach-Zehnder modulators made by bonding an unetched thin film of lithium niobate (LN) to a second chip with rib waveguides in another material, such as silicon. Devices were fabricated after storing bonded silicon-LN chips in a common laboratory environment for more than three years. The chips survived the full processing flow and yielded modulators with greater than 50 GHz 3 dB electro-optic bandwidth, and V π L less than 3 V cm at 1550 nm and equivalent performance to freshly-bonded and processed chips. Furthermore, we demonstrate the co-integration of hybrid bonded thin-film LN modulators and silicon photonics based high quality-factor ring resonators and higher-order coupled microring optical filters. The silicon microring resonators are used for photon-pair generation at 1550 nm using spontaneous four-wave mixing. These results show the feasibility of a modular modulator fabrication procedure, where the planarization and bonding steps are performed for a batch of chips at one time and smaller sub-batches are customized by end users at a much later time according to their needs and convenience.