CMOS-compatible photonic integrated circuits on thin-film ScAlN

CMOS-compatible photonic integrated circuits on thin-film ScAlN

APL Photonics

10.1063/5.0208517

http://dx.doi.org/10.1063/5.0208517

Sihao Wang, Veerendra Dhyani, Sakthi Sanjeev Mohanraj, Xiaodong Shi, Binni Varghese, Wing Wai Chung, Ding Huang, Zhi Shiuh Lim, Qibin Zeng, Huajun Liu, Xianshu Luo, Victor Leong, Nanxi Li, Di Zhu

17 June 2024

Wang, S., Dhyani, V., Mohanraj, S. S., Shi, X., Varghese, B., Chung, W. W., Huang, D., Lim, Z. S., Zeng, Q., Liu, H., Luo, X., Leong, V., Li, N., & Zhu, D. (2024). CMOS-compatible photonic integrated circuits on thin-film ScAlN. APL Photonics, 9(6). https://doi.org/10.1063/5.0208517

Scandium aluminum nitride (ScAlN) has recently emerged as an attractive material for integrated photonics due to its favorable nonlinear optical properties and compatibility with complementary metal–oxide semiconductor (CMOS) fabrication. Despite the promising and versatile material properties, it is still an outstanding challenge to realize low-loss photonic circuits on thin-film ScAlN-on-insulator wafers. Here, we present a systematic study on the material quality of sputtered thin-film Sc0.1Al0.9N produced in a CMOS-compatible 200 mm line, including its crystallinity, roughness, and second-order optical nonlinearity, and developed an optimized fabrication process to yield 400 nm thick, fully etched waveguides. With surface polishing and annealing, we achieve micro-ring resonators with an intrinsic quality factor as high as 1.47 × 105, corresponding to a propagation loss of 2.4 dB/cm. These results serve as a critical step toward developing future large-scale, low-loss photonic integrated circuits based on ScAlN.

Publisher Copyright

This research / project is supported by the Agency for Science, Technology and Research - DeltaQ 2.0
Grant Reference no. : C230917005

This research / project is supported by the Agency for Science, Technology and Research - Central Funds - Council Strategic Fund - SERC
Grant Reference no. : C220415015

This research / project is supported by the Agency for Science, Technology and Research - Industry Alignment Fund - Pre-Positioning Programme (IAF-PP)
Grant Reference no. : M23M5a0069

This research / project is supported by the National Research Foundation - Quantum Engineering Program 2.0
Grant Reference no. : NRF2022-QEP2-01-P07

This research / project is supported by the National Research Foundation - NRF Fellowship
Grant Reference no. : NRF-NRFF152023-0005

This research / project is supported by the National Research Foundation - Competitive Research Programme
Grant Reference no. : NRF-CRP28-2022-0002

https://oar.a-star.edu.sg/communities-collections/articles/20310

2378-0967

Institute of Materials Research & Engineering

https://doi.org/10.1063/5.0208517