Spin-Coated Erbium-Doped Silica Sol-Gel Films on Silicon

TL;DR

This paper demonstrates the fabrication of erbium-doped silica thin films on silicon using a sol-gel spin-coating process, which exhibit infrared emission and enhance silicon's band-gap emission, with implications for opto-electronic devices.

Contribution

It introduces a novel sol-gel spin-coating method for creating erbium-doped silica films on silicon with enhanced optical properties.

Findings

Infrared emission at 1.5 microns from erbium ions

~100X enhancement of silicon band-gap emission

Successful fabrication of ~130 nm thick erbium-doped silica films

Abstract

This work reports optical functionality contained in, as well as and produced by, thin film coatings. A sol-gel process, formulated with precursor active ingredients of erbium oxide and tetraethylorthosilicate (TEOS), was used for spin-coating thin (~130 nm) erbium-doped (~6 at. %) silica films on single-crystal silicon. Annealed films produce infrared emission in the 1.5-micron band from erbium ions in the film, as well as greatly enhancing (~100X) band-gap emission from the underlying silicon. The distinctly different mechanisms for the two modes of optical activities are interpreted in terms of optical emission theory and modeling; prospects for opto-electronic applications are discussed.