Thermally stable ohmic contacts to n-type GaAs. V. Metal-semiconductor field-effect transistors with NiInW ohmic contacts

Journal Article · Mon May 01 00:00:00 EDT 1989 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.342629· OSTI ID:6409528

Murakami, M; Price, W H; Greiner, J H; Feder, J D; Parks, C C

Thermal stability of self-aligned refractory metal-semiconductor field-effect transistors (MESFETs) with the universally used AuNiGe ohmic contact metallurgy or the recently developed NiInW ohmic contact metallurgy has been studied. In these devices WSi/sub 0.1/ films with length down to 1 ..mu..m were used as the gate material, and AlCu was used as the overlayer material on the ohmic contacts, where a very thin Ti layer was deposited prior to the AlCu deposition. The performance of the as-fabricated devices with the NiInW ohmic contacts was as good as those with the AuNiGe ohmic contacts. During subsequent annealing at 400 /sup 0/C, deterioration of the device performance (defined by the decrease in the FET square-law coefficient) was observed after annealing at 400 /sup 0/C for 2 h in the devices with the AuNiGe ohmic contacts. However, excellent stability was observed in the devices with the NiInW ohmic contacts; no deterioration was observed at 400 /sup 0/C for 180 h, 450 /sup 0/C for 18 h, and 500 /sup 0/C for 2 h. The device deterioration with NiInW contacts, which was observed after annealing for longer times, is believed to be due to an increase in the contact resistances caused by In movement away from the metal/GaAs interfaces. Based on this assumption, an activation energy for In diffusion in GaAs was determined from onset times of the device deterioration to be /similar to/2.0 eV, which is close to the reported value of 1.9 eV.

• Research Organization: IBM Research Division, T. J. Watson Research Center, Yorktown Heights, New York 10598
• OSTI ID: 6409528
• Journal Information: J. Appl. Phys.; (United States), Vol. 65:9
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
FIELD EFFECT TRANSISTORS
FABRICATION
GALLIUM ARSENIDES
PHYSICAL PROPERTIES
INDIUM
NICKEL
TUNGSTEN
ANNEALING
ELECTRIC CONDUCTIVITY
ELECTRIC CONTACTS
HIGH TEMPERATURE
N-TYPE CONDUCTORS
STABILITY
THERMODYNAMIC PROPERTIES
TUNGSTEN SILICIDES
ARSENIC COMPOUNDS
ARSENIDES
ELECTRICAL EQUIPMENT
ELECTRICAL PROPERTIES
ELEMENTS
EQUIPMENT
GALLIUM COMPOUNDS
HEAT TREATMENTS
MATERIALS
METALS
PNICTIDES
REFRACTORY METAL COMPOUNDS
SEMICONDUCTOR DEVICES
SEMICONDUCTOR MATERIALS
SILICIDES
SILICON COMPOUNDS
TRANSISTORS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TUNGSTEN COMPOUNDS
360104* - Metals & Alloys- Physical Properties
420800 - Engineering- Electronic Circuits & Devices- (-1989)