11:15 〜 11:30
▼ [16a-421-10] Fabrication of High Q-Factor Ring Resonator using LSCVD Si3N4 Film
キーワード：Ring Resonator, High Q-factor, Liquid Source CVD
In this work, we investigate the fabrication of a high Q-factor Si3N4 ring resonator by improving the propagation loss and controlling the precise control of the coupling intensity. Generally, the Si3N4 film was deposited on the SiO2/Si substrate by using PECVD or LPCVD technique. However, as-deposited Si3N4 has dangling H and O bonds with Si and N in the films. These bonds have an intense absorption centered at 1520 nm, which overlaps with c-band and causes the excess propagation losses. In order to overcome this problem, we prepared Si3N4 films using the liquid source CVD (LSCVD). It turns out to be both refractive index and propagation loss can be effective optimized. In the fabrication of the Si3N4 ring resonator, different parameters of the ring structure are discussed in order to obtain a high- Q resonance. The measured Q factor was 70,800 and it can be further improved with increased optical confinement and film deposition optimization. When the effective refractive index assumed to change 10-4, a resonance spectral shift of 0.093 nm can be theoretically obtained with the corresponding extinction ratio of 6 dB. Thus, a modulated depth of 3 dB within the wavelength shift of 0.046 nm is also achieved. The proposed device shows potential for high-speed, low-energy, and small-footprint optical switch and modulator application.