Impacts of Tapered Sidewall Profiles With High Aspect Ratio on Subwavelength Grating Structure

We have numerically demonstrated the significant impacts on the resonance mode characteristics of subwavelength grating structures due to tapered sidewall profile and high aspect ratio, which is normally obtained due to the practical CMOS-compatible fabrication and etching processes. Our simulation results have revealed that the tapered sidewall profile with high aspect ratio plays important roles on the resonance mode behavior of subwavelength grating photonic devices. The coupling mechanism between the guided mode resonance and the grating cavity is also emphasized. Our numerical studies can be utilized for a series of integrated photonic devices applications, such as compact optical filter, photonic amplifier, and lasers, while considering realistic subwavelength grating structures due to current nanoelectronics fabrication process.