The influence of residual contamination on the structure and properties of metal/GaAs interfaces

Conference · Sat Oct 01 04:00:00 EDT 1988

DOI:https://doi.org/10.1007/978-1-4684-5709-4_12· OSTI ID:5551131

Liliental-Weber, Z.

This study shows that interface morphology, orientation relationship, and formation of new phases strongly depend on the surface preparation of GaAs before metal deposition and/or on the annealing environment. The metals investigated (Au, Ag, and Al, with lattice parameters close to each other) deposited in situ on a UHV-cleaved GaAs surface show very similar relationships with GaAs upon annealing. This relationship changes when GaAs is exposed to air before metal deposition. All metals investigated, when deposited on UHV-cleaved GaAs substrate, are stable upon annealing. The interface between metal and GaAs remains abrupt upon annealing. In the case of Cr almost perfect matching to GaAs was observed for UHV deposited samples, but random orientation for air-exposed samples. This study shows that impurities at the semiconductor surface can affect the stability of the barrier height of Schottky contacts. These changes in barrier height depend on the metal used, and on the intensity and direction of the potential and current during the electrical aging. The dramatic example of Ag contacts and their change upon current stressing only for air-exposed samples confirms the importance of surface preparation before metalization. 34 refs., 7 figs., 1 tab.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• Sponsoring Organization: DOD; DOE/ER
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5551131
• Report Number(s): LBL-26140; CONF-8811270--1; ON: DE90000549; CNN: N00014-86-K-0668
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602 -- Other Materials-- Structure & Phase Studies
42 ENGINEERING
420800* -- Engineering-- Electronic Circuits & Devices-- (-1989)
ALUMINIUM
ANNEALING
ARSENIC COMPOUNDS
ARSENIDES
CHROMIUM
CRYSTAL STRUCTURE
DEPOSITION
ELECTRIC CONTACTS
ELECTRICAL EQUIPMENT
ELEMENTS
EQUIPMENT
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
GOLD
GRAIN SIZE
HEAT TREATMENTS
IMPURITIES
INTERFACES
MATERIALS
METALS
MICROSTRUCTURE
PNICTIDES
SEMICONDUCTOR DEVICES
SEMICONDUCTOR MATERIALS
SILVER
SIZE
TRANSITION ELEMENTS