Improved CMOS-compatible ultra-silicon-rich nitride for non-linear optics

Doris K. T. Ng; P. Xing; George F. R. Chen; H. Gao; Y. Cao; Dawn T. H. Tan

doi:10.1117/12.2582841

5 March 2021 Improved CMOS-compatible ultra-silicon-rich nitride for non-linear optics

Doris K. T. Ng, P. Xing, George F. R. Chen, H. Gao, Y. Cao, Dawn T. H. Tan

Proceedings Volume 11682, Optical Components and Materials XVIII; 116820L (2021) https://doi.org/10.1117/12.2582841
Event: SPIE OPTO, 2021, Online Only

Abstract

We present an improved CMOS-compatible USRN material prepared using DCS-based chemistry deposited at a low temperature of ~300°C. Morphology and composition of these USRN films are characterized using SEM, TEM, EDS and AFM. Surface profilometer is also used to estimate the film stress over an 8-inch wafer. TEM shows that the USRN film is amorphous and AFM measures a low roughness RMS of ~0.4 nm over a scan window of 3 μm x 3 μm. Optical properties of these USRN films are studied using variable-angle spectroscopic ellipsometry and FTIR spectroscopy. A prism coupler is used to estimate the film propagation loss. Ellipsometry measurement shows refractive index of around 3.09 at 1550 nm wavelength, which is our wavelength of interest. Comparing with USRN films prepared using SiH_4- based chemistry, FTIR characterization shows reduced absorbance for films prepared using DCS-based chemistry at wavenumber region where Si-H bonds are located. The absorbance caused by N-H bonds are comparable for USRN films prepared using both DCS-based and SiH_4-based chemistries. Si-H bonds and N-H bonds are expected to be the main sources of material absorption near 1550 nm in the USRN material. Characterization results of waveguides fabricated using USRN deposited by this DCS-based chemistry shows propagation loss of ~4.9 dB/cm for waveguide width of 1.5 μm at 1550 nm wavelength. The improved results of DCS-based USRN will help to further cut losses and therefore enhance the performance of CMOS compatible USRN devices in nonlinear signal processing.

Conference Presentation

Citation Download Citation

Doris K. T. Ng, P. Xing, George F. R. Chen, H. Gao, Y. Cao, and Dawn T. H. Tan "Improved CMOS-compatible ultra-silicon-rich nitride for non-linear optics", Proc. SPIE 11682, Optical Components and Materials XVIII, 116820L (5 March 2021); https://doi.org/10.1117/12.2582841

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available