Enchanced reflectance SiN$_x$ / SiO$_x$ DBR mirror based on TEOS precursor fabricated by PECVD method

TL;DR

This study compares the optical qualities of SiN$_x$/SiO$_x$ DBR mirrors fabricated using TEOS and SiH$_4$ precursors, demonstrating that TEOS yields significantly better reflectivity and lower surface roughness.

Contribution

It provides experimental evidence that TEOS precursor improves the optical quality and surface smoothness of SiN$_x$/SiO$_x$ DBR mirrors compared to SiH$_4$.

Findings

TEOS-based mirrors have 20% higher reflectivity.

Optical losses are halved with TEOS.

Surface roughness reduced by a factor of five with TEOS.

Abstract

In this study, we investigated the influence of silicon oxide roughness produced from the gas precursor monosilane (SiH$_4$) and the silicon-organic precursor tetraethoxysilane (TEOS) on the optical qualities of a distributed Bragg reflector (DBR). A significant influence of the precursors from which SiOx is deposited on the optical qualities of DBR mirrors is demonstrated in this study. It has been shown experimentally that a mirror produced from the TEOS precursor is endowed with better qualities than a mirror produced using SiH4, that is, the reflectivity increased by 20% and optical losses decreased by half. The roughness average (Ra) of the SiN$_x$/SiO$_x$ / (TEOS) mirror surface decreased by a factor of five compared to that of the SiN$_x$/SiO$_x$ / (SiH4) mirror