Accession Number : ADP007904

Title :   Oxide Layer Growth on Gallium Arsenide using a High Kinetic Energy Atomic Oxygen Beam,

Corporate Author : LOS ALAMOS NATIONAL LAB NM

Personal Author(s) : Hoffbauer, M. A. ; Cross, J. B. ; Farr, J. D. ; Bermudez, V. M.

Report Date : 22 MAY 1992

Pagination or Media Count : 3

Abstract : The inherent theoretical advantages of GaAs electronic devices over those employing Si technology are severely limited in practice by the difficulty of forming passivating oxide layers. Problems encountered with oxide stoichiometry, crystallinity, interface defects, and chemical stability have been the subjects of numerous studies over the last 15 years. One of the major factors contributing to these problems is the differing rates of oxidation of Ga and As and the volatility of the As2O3 and As2O5 products at temperatures above -100 deg C. A number of different approaches to the growth of device-quality native oxides at low temperatures on GaAs have been attempted including: the use of ozone; simultaneous 02 and electron beam exposure ; photoexcitation of electron-hole'pairs in the GaAs, ; the use of more reactive oxidizers such as N2O; photochemical excitation of the gas-phase molecular species. addition of H2O to the excitation of 02 with a hot filament or a Tesla discharge; and plasma excitation of the 02. Although, many of these techniques can greatly increase the rate of formation of the first few monolayers of oxide, they are generally unsuccessful in the growth of >100 Angstrom thick oxide layers. Further, the oxidation reactions do not result in Ga or As in their highest formal oxidation state, and the resulting oxide is usually deficient in Ga or As. Recently, we have began investigating the oxidation of GaAs with a high kinetic energy beam of atomic oxygen and using x-ray photoemission (XPS) and Raman spectroscopies to characterize the thickness and stoichiometry of the oxide and to probe the oxide/GaAs interface.

Descriptors :   *OXIDATION, *GALLIUM ARSENIDES, ADDITION, APPROACH, ELECTRONICS, ENERGY, EXCITATION, FILAMENTS, INTERFACES, KINETIC ENERGY, KINETICS, LAYERS, OXIDES, OXYGEN, OZONE, PHASE, PHOTOELECTRIC EMISSION, PROBES, QUALITY, RATES, STABILITY, STOICHIOMETRY, TEMPERATURE, THICKNESS, VOLATILITY, MOLECULAR BEAMS, X RAY PHOTOELECTRON SPECTROSCOPY.

Subject Categories : Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE