Table of Contents
Laser Chemistry
Volume 5, Issue 1, Pages 1-10
http://dx.doi.org/10.1155/LC.5.1

Neutral and Ionic Particle Emission Produced by Laser Irradiation of a GaAs Surface

Akzo Research Laboratories Arnhem, Corporate Research Department, Postbox 60, Arnhem 6800 AB, The Netherlands

Received 28 October 1983; Accepted 1 February 1984

Copyright © 1984 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The emission of gas phase particles from a GaAs surface, due to irradiation at 1064 nm by an unfocussed Q-switched Nd:YAG laser beam, has been studied. Mass spectra have been recorded with the aid of a quadrupole mass spectrometer, and the ion-neutral ratio of the emitted particles has been measured with an electrical diode set up. The applied incident laser radiation power density was varied in the range 1.2–9.6 × 107 Watts/cm2 and was delivered as 10 ns (fwhm) long pulses. It appeared that mainly Ga atoms and As2 molecules were emitted, together with minor amounts (<1%) of Ga2 and GaAs molecules. Besides the emission of neutral particles, the formation of Ga+ atomic ions was observed. By measuring the ratio of Ga+ ions and Ga neutral atoms it could be shown that the (ionic) particle emission is governed by a thermal mechanism for 1064 nm incident radiation. This latter experimental result differs from that obtained if a ruby laser (694 nm) is used as the radiation source.