Institute for Materials Chemistry and Engineering, Kyushu University, 6-1 Kasuga, Fukuoka 810-8580, Japan.
Opt Lett. 2012 Oct 1;37(19):4086-8. doi: 10.1364/OL.37.004086.
To fabricate athermal silicon nitride waveguides, the dimensions of both the core and cladding, refractive index, and thermo-optic coefficients must be controlled precisely. We present a simple and effective method for the postfabrication trimming of silicon nitride ring resonators that overcomes the highly demanding fabrication. In order to manipulate the polymer's refractive index and thermo-optic coefficient, we bleached the Disperse Red 1-doped poly(methyl methacrylate) (DR1/PMMA) top cladding using UV irradiation. After a suitable bleaching time, the temperature-dependent wavelength shift of the ring resonator was reduced from -9.8 to -0.018 pm/°C, which is the lowest shift that we are aware of for an athermal waveguide realized by overlaying a polymer cladding to date.
为了制造无热硅氮化物波导，必须精确控制芯层和包层的尺寸、折射率和热光系数。我们提出了一种简单有效的后制造硅氮化物环形谐振器修整方法，克服了高要求的制造工艺。为了控制聚合物的折射率和热光系数，我们使用紫外线辐照对掺有分散红 1 的聚甲基丙烯酸甲酯（DR1/PMMA）上包层进行漂白。在适当的漂白时间后，环形谐振器的温度相关波长漂移从-9.8 降低到-0.018 pm/°C，这是我们迄今为止所知的通过在聚合物包层上覆盖来实现无热波导的最低漂移。
