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Title: Thermo-optic properties of silicon-rich silicon nitride for on-chip applications

We demonstrate the thermo-optic properties of silicon-rich silicon nitride (SRN) films deposited using plasma-enhanced chemical vapor deposition (PECVD). Shifts in the spectral response of Mach-Zehnder interferometers (MZIs) as a function of temperature were used to characterize the thermo-optic coefficients of silicon nitride films with varying silicon contents. A clear relation is demonstrated between the silicon content and the exhibited thermo-optic coefficient in silicon nitride films, with the highest achievable coefficient being as high as (1.65±0.08) ×10−4K-1. Furthermore, we realize an SRN multi-mode interferometer (MMI) based thermo-optic switch with over 20 dB extinction ratio and total power consumption for two-port switching of 50 mW.

 
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Award ID(s):
1707641 1901844
NSF-PAR ID:
10182715
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Express
Volume:
28
Issue:
17
ISSN:
1094-4087; OPEXFF
Page Range / eLocation ID:
Article No. 24951
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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