Li Gaoyuan, Fu Meicheng, Zheng Yi, Guan Xiaowei
Opt Lett. 2020 Sep 15;45(18):5012-5015. doi: 10.1364/OL.400644.
Titanium dioxide () microring resonators (MRRs) with high quality factors (Qs) are demonstrated by using a new, to the best of our knowledge, bottom-up fabrication method. Pattern platforms with a T-shaped cross section are first defined by etching a thin top layer of silicon nitride and a thick bottom layer of silica and partially undercutting the silica. Then, is deposited on the platforms to form the waveguides and devices. MRRs with different bending radii, waveguide widths, and gaps in the bus waveguide are fabricated and measured. The intrinsic () is achieved to be ∼1.1×10 at the telecommunication wavelengths, corresponding to a bend waveguide loss of 3.9 dB/cm while the compact MRR with a radius of 10 µm can still sustain a of ∼10. These results not only unfold the feasibilities of the proposed bottom-up method for fabricating waveguides and MRRs with high Qs and compact footprints but also suggest a new approach for fabricating waveguides in other materials, of which direct etching is not easily accessible.
据我们所知，通过使用一种全新的自下而上的制造方法，展示了具有高品质因数（Qs）的二氧化钛（）微环谐振器（MRRs）。首先通过蚀刻氮化硅薄顶层和二氧化硅厚底层并对二氧化硅进行部分底切来定义具有T形横截面的图案平台。然后，在平台上沉积以形成波导和器件。制造并测量了具有不同弯曲半径、波导宽度和总线波导间隙的MRRs。在电信波长下，本征（）达到约1.1×10，对应弯曲波导损耗为3.9 dB/cm，而半径为10 µm的紧凑型MRR仍可维持约10的。这些结果不仅揭示了所提出的自下而上方法用于制造具有高Qs和紧凑尺寸的波导和MRRs的可行性，还为在其他难以进行直接蚀刻的材料中制造波导提出了一种新方法。
