Stable violet cathodoluminescence of α-quartz after Ge+ implantation at elevated temperature

Abstract

Doping single-crystalline α-quartz with 120keV Ge+-ion implantation under the conditions of dynamic solid phase epitaxial regrowth has been studied as function of ion fluence and substrate temperature. In particular, the light emitting properties possibly suitable for optoelectronic devices have been investigated by measuring cathodoluminescence spectra for implantation temperatures from 300 to 1223K and for analyzing temperatures from 10−300K. Rutherford backscattering channeling analysis showed that the Ge implantation produced amorphous layers varying in depth with temperature. At a fluence of 7×1014Ge-ions∕cm2 and an implantation temperature of 1073K, Ge implantation is accompanied by a strong increase in the luminescence intensity of a violet band, which we associate with Ge-related defects or Ge clusters. This violet band is very stable and has a long lifetime of 6μs. All the other bands observed are connected to known oxygen defect centers in the SiO2 network.