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Abstract Silicon carbide (SiC)'s nonlinear optical properties and applications to quantum information have recently brought attention to its potential as an integrated photonics platform. However, despite its many excellent material properties, such as large thermal conductivity, wide transparency window, and strong optical nonlinearities, it is generally a difficult material for microfabrication. Here, it is shown that directly bonded silicon‐on‐silicon carbide can be a high‐performing hybrid photonics platform that does not require the need to form SiC membranes or directly pattern in SiC. The optimized bonding method yields defect‐free, uniform films with minimal oxide at the silicon–silicon–carbide interface. Ring resonators are patterned into the silicon layer with standard, complimentary metal–oxide–semiconductor (CMOS) compatible (Si) fabrication and measure room‐temperature, near‐infrared quality factors exceeding 105. The corresponding propagation loss is 5.7 dB cm−1. The process offers a wafer‐scalable pathway to the integration of SiC photonics into CMOS devices.
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Fabrication of Localized Silicon-on-Insulator Based Rhombus-Shaped Channels in Silicon
Fabricating localized silicon-on-insulator (LSOI) on bulk silicon eliminates the need for using expensive SOI wafers for silicon waveguides and MEMS applications. One of the most important building blocks in silicon photonics is optical waveguide, which usually consists of silicon surrounded by silicon dioxide with refractive indices of 3.5 and 1.5, respectively. It was observed that the SOI wafer puts restrictions on the integration of electronics and photonics because the buried oxide is too thin for field confinement. Hence, fabrication of LSOI in standard silicon wafers is considered to have precise control of the oxide thickness which will lead to effective integration of electronic and photonic devices. We used rhombus-shaped channel method in the fabrication of LSOI structure that can be produced on any part of a bulk silicon wafer.
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- Award ID(s):
- 1643788
- PAR ID:
- 10274707
- Date Published:
- Journal Name:
- ECS Meeting Abstracts
- Volume:
- Volume MA2019-01
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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