Ion beam doping and epitaxial regrowth of α-quartz

Abstract

Thermally induced epitaxial crystallization of thin a-SiO 2 films represents a promising procedure for removing the ion-beam damage induced during the fabrication of integrated optical devices. In this paper we report on the crystallization of a-SiO 2 films deposited on single crystalline α-quartz substrates, investigated by means of Rutherford backscattering spectrometry in channeling geometry (RBS-C). The epitaxial crystallization was achieved by means of a novel three-step procedure which uses high-fluence Cs +-ion doping of the films and subsequent annealing in air at 800–900°C. Similarly, amorphous SiO 2 layers, created by the ion irradiation of α-quartz samples, were epitaxially regrown after alkali post-implantation and annealing, thus demonstrating that the regrowth is independent of the production history of the amorphous film. Optical spectroscopy in the range 300–1100 nm showed the good optical properties of the regrown layer.