Improvement of the interface quality during thermal oxidation of Al0.98Ga0.02As layers due to the presence of low-temperature-grown GaAs

Abstract

The role of a low-temperature-grown GaAs (LT GaAs) layer on the lateral oxidation of an Al0.98Ga0.02As/GaAs layer structure has been studied by transmission electron microscopy. Results show that structures incorporating LT GaAs develop better quality oxide/GaAs interfaces compared to reference samples without LT GaAs. While the latter have As accumulation in the vicinity of these interfaces, the structures with LT layers display sharper oxide–GaAs interfaces with a reduced concentration of As. These results are explained in terms of the high Ga vacancy concentration in the LT GaAs and the possible influence of those vacancies in enhancing As diffusion away from the oxide–semiconductor interface.

Observation of the Purcell effect in high-index-contrast micropillars

“…Large variations in quality factors and mode wavelengths between nominally identical pillars result from susceptibility of these structures to variations in pillar diameter and/or spacer layer thickness. Future improvements could be made through refining our processing or by utilising growth techniques which can reduce variations in layer thickness across the sample [16,17]. CCD intensity (arb units)…”

GaAs metal–oxide–semiconductor field-effect transistor with nanometer-thin dielectric grown by atomic layer deposition

“…͓DOI: 10.1063/1.1590743͔ GaAs metal-oxide-semiconductor field-effect transistor ͑MOSFET͒ has attracted great interest for decades. [1][2][3][4][5][6][7][8][9][10][11][12][13] GaAs-based devices potentially have great advantages over Si-based devices for high-speed and high-power applications, in part from an electron mobility in GaAs that is ϳ5ϫ greater than that in Si, the availability of semi-insulating GaAs substrates, and higher breakdown field. Currently, the metal-semiconductor field-effect transistor ͑MESFET͒ is the dominant GaAs device for high-speed and microwave circuits.…”

Ultralow-threshold cryogenic vertical-cavity surface-emitting laser with AlAsoxide–GaAs distributed Bragg reflectors

“…Using ternary A1 0.95 Ga 0.05 As alloy and thin AlGaAs buffer layers is shown to enhance the quality and stability of oxide DBRs. [18][19][20] The top DBR is completed by phase matching 46 nm GaAs layer and metal layer the wavelength ϳ930 nm and a stop band of 500 nm. The bottom output DBR consists of 24.5 periods of AlAs and GaAs / 4 layers uniformly doped with Si ͑2 ϫ 10 18 cm −3 ͒.…”