Structure and photoluminescence of Ge nanoclusters embedded in GeOx films deposited using laser assistance at low temperature

Abstract

Crystalline Ge nanocluster-embedded GeOx films were deposited at low temperature using a laser-assisted plasma enhanced chemical-vapor deposition system. The structural and optical properties of the films deposited under various power densities of the assisting CO2 laser beam were investigated. The size of the Ge nanoclusters decreased and the number density of the Ge nanoclusters increased with an increase in the laser power used in the film deposition. The Ge nanoclusters crystallization was improved with an increase in the assisting laser power. The observed photoluminescence (PL) characteristics, including the spectral position, decay curve, and intensity of the emission bands, can be attributed to the quantum confinement effect. These experimental results verified that the PL emission originated from the recombination of electron-hole pairs in the Ge nanoclusters. Furthermore, the growth process of the Ge nanoclusters was qualitatively studied.

Freestanding Ge/GeO2 Core‐Shell Nanocrystals with Varying Sizes and Shell Thicknesses: Microstructure and Photoluminescence Studies

“…Such high temperature processing is not compatible for the fabrication of electronic devices and also it can degrade the device performance. Recently, Tsai et al [13] synthesized Ge NCs embedded in GeO x film at low temperature without postannealing by using CO 2 laser-assisted chemical vapour deposition technique and studied its microstructure and light emission property. Here we synthesized isolated freestanding Ge/GeO 2 core-shell NCs with varying shell thicknesses by employing simple mechanical ball milling.…”