This article presents the results of the study of the influence of the most significant parameters of the side wall roughness of an ultra-thin silicon nitride lightguide layer of multimode integrated optical waveguides with widths of 3 and 8 microns. The choice of the waveguide width was made due to the need to provide multimode operation for telecommunication wavelengths, which is necessary to ensure high integration density. Scattering in waveguide structures was measured by optical frequency domain reflectometry (OFDR) of a backscattering reflectometer. The finite difference time domain method (FDTD) was used to study the effect of roughness parameters on optical losses in fabricated waveguides, the roughness parameters that most strongly affect optical scattering were determined, and methods of its significant reduction were specified. The prospects for implementing such structures on a quartz substrate are justified.
This article presents the results of a computer simulation of whispering gallery modes in the structure of a silicon disk resonator with a wedge-shaped profile made on a silicon-on-isolator base (SOI). The rationale for the choice of silicon as a material for its manufacturing is given. The results of the study of the influence of the wedge angle on the whispering gallery mode parameters (WGM) are presented. The optimum wedge angle of a silicon disk resonator is determined, which ensures the minimum loss and maximum mode stability. The technological aspects of plasma-chemical etching processes for forming a wedge-shaped profile of the edge of a silicon disk resonator are studied.
This article presents a silicon disk resonator of the whispering-gallery-mode (WGM) type. The calculated Q-factor of the silicon WGM resonator was 107. Two methods of studying the surface roughness of a silicon WGM resonator with a nonlinear profile by means of Helios 650 scanning electron microscope and Bruker atomic force microscope (AFM) are presented. The results obtained by the two methods agreed well with each other. A comparison of the surface roughness values of WGM resonators manufactured using different technological approaches is presented. Based on the obtained data, a preliminary estimated Q-factor calculation of the resonators was performed, which was refined by numerical calculation using the finite-difference time-domain (FDTD) method. The effect of the surface roughness of the resonator on its Q-factor was found. Reducing the surface roughness of the resonator from 30 nm to 1–2 nm led to an increase in its Q-factor from 104 to 107.
Представлены основные конструктивно-технологические методы создания
интегрально-оптических элементов. Показано, что современные базовые оптические логические элементы («И», «ИЛИ», «И-НЕ», «ИЛИ-НЕ») могут быть реализованы двумя основными методами: на интегрально-оптических структурах, содержащих в своем составе интерферометры Маха-Цендера и микрорезонаторы, и на двумерных
фотонных кристаллах. Перечислены основные преимущества и конструктивно-технологические особенности каждого из методов создания интегрально-оптических
логических элементов (ИОЛЭ) для создания перспективных фотонных интегральных схем (ФИС).