A combination of rapid thermal processing and photochemical deposition for the growth of SiO2 suitable for InP device applications

Abstract

A combination of ultraviolet and infrared lamps is used to obtain the growth of SiO2 on InP substrates at low temperature under rapid thermal processing conditions. Thorough infrared spectroscopy characterization of the dielectric layers shows that the ultraviolet-assisted growth process without mercury sensitization leads to good quality silica interspersed with oxygen-deficient inclusions. Rapid annealing improves them so as to be suitable for InP-based field-effect devices, with interface trap density around 5×1011 cm−2. A study of the interface trap density made with this technique shows the relevance of fast thermal processing, even at low growth temperatures, for the improvement of these devices.