Optical properties of nitride-rich SiNx and its use in CMOS-compatible near-UV Bragg filter fabrication

Nitride-rich silicon-nitride (SiNx) is being explored for its potential as a suitable optical material for use in microsystems operating in the near-UV spectral range. Although silicon-rich SiNx is widely accepted as a CMOS-compatible dielectric and micromechanical material, its optical absorption l...

Full description

Saved in:
Bibliographic Details
Main Authors: Reinoud F. Wolffenbuttel, Declan Winship, Yutao Qin, Yogesh Gianchandani, David Bilby, Jaco H. Visser
Format: Article
Language:English
Published: Elsevier 2024-12-01
Series:Optical Materials: X
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2590147824000603
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Nitride-rich silicon-nitride (SiNx) is being explored for its potential as a suitable optical material for use in microsystems operating in the near-UV spectral range. Although silicon-rich SiNx is widely accepted as a CMOS-compatible dielectric and micromechanical material, its optical absorption limits application to the visible to near-IR spectral range. However, this work shows that a balance can be achieved between a sufficiently high index of refraction (n> 2) and an acceptable optical loss (k<10−3) in nitride-rich SiNx of appropriate composition (x∼1.45). Bragg reflectors with a design wavelength at λo= 330 nm are used for validation. PECVD is used for sample preparation and experiments confirm that the spectral range available for use of SiNx-based optical microsystems extends to wavelengths as low as 300 nm.
ISSN:2590-1478