Shi Xiaodong, Lu Yaoqin, Chaussende Didier, Rottwitt Karsten, Ou Haiyan
Department of Electrical and Photonics Engineering, Technical University of Denmark, rsteds Plads, Building 343, 2800 Lyngby, Denmark.
Université Grenoble Alpes, CNRS, Grenoble INP, SIMaP, 38000 Grenoble, France.
Materials (Basel). 2023 Mar 14;16(6):2324. doi: 10.3390/ma16062324.
Silicon carbide (SiC) has become a promising optical material for quantum photonics and nonlinear photonics during the past decade. In this work, we propose two methods to improve the 4H-SiC thin film quality for SiC integrated photonic chips. Firstly, we develop a wet-oxidation-assisted chemical mechanical polishing (CMP) process for 4H-SiC, which can significantly decrease the surface roughness from 3.67 nm to 0.15 nm, thus mitigating the light scattering loss. Secondly, we find that the thermal annealing of the 4H-SiC devices at 1300 °C can help to decrease the material absorption loss. We experimentally demonstrate that the wet-oxidation-assisted CMP and the high-temperature annealing can effectively increase the intrinsic quality factor of the 4H-SiC optical microring resonators.
在过去十年中，碳化硅（SiC）已成为用于量子光子学和非线性光子学的一种很有前景的光学材料。在这项工作中，我们提出了两种方法来提高用于SiC集成光子芯片的4H-SiC薄膜质量。首先，我们开发了一种用于4H-SiC的湿氧化辅助化学机械抛光（CMP）工艺，该工艺可将表面粗糙度从3.67纳米显著降低至0.15纳米，从而减轻光散射损耗。其次，我们发现4H-SiC器件在1300°C下进行热退火有助于降低材料吸收损耗。我们通过实验证明，湿氧化辅助CMP和高温退火可以有效地提高4H-SiC光学微环谐振器的本征品质因数。
