Tantalum nitride and tungsten as diffusion barriers for palladium and cobalt silicides in multilayer metallization schemes

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:7154817

Farooq, M S

The efficiency of two thin-film diffusion barriers to be used in silicide/aluminum metallization schemes for silicon integrated circuits were evaluated. Control samples of Si/CoSi{sub 2}/Al and Si/Pd{sub 2}Si/Al, and test samples of Si/CoSi{sub 2}/Ta{sub 2}N/Al, Si/CoSi{sub 2}/W/Al and Si/Pd{sub 2}Si/Ta{sub 2}N/Al were used for sheet resistance, X-ray diffraction, Rutherford backscattering, and Auger-electron spectroscopic measurements. TEM studies were carried out on representative samples to examine the nature of the interfaces. Results from the analytical tests indicated that all three types of test samples are resistant to gross diffusion and intermixing of Co, Pd, Al and Si. They also showed that in the control samples, annealing causes interdiffusion of these species, necessitating the presence of a diffusion barrier. For test contacts, results demonstrated that although diffusion barriers may be successful in preventing metallurgical interdiffusion, they may not be viable in integrated circuit technology. Possible modifications were identified to eliminate the high contact resistance in the CoSi{sub 2} devices. It was determined that the Si/Pd{sub 2}Si/Ta{sub 2}N/Al devices perform excellently despite annealing, indicating that the scheme may be successfully applied in VLSI technology.

• Research Organization: Rutgers--the State Univ., New Brunswick, NJ (USA)
• OSTI ID: 7154817
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601 -- Other Materials-- Preparation & Manufacture
42 ENGINEERING
426000* -- Engineering-- Components
Electron Devices & Circuits-- (1990-)
COBALT COMPOUNDS
COBALT SILICIDES
DIFFUSION BARRIERS
ELECTRONIC CIRCUITS
ELEMENTS
EVALUATION
FABRICATION
FILMS
INTEGRATED CIRCUITS
METALS
MICROELECTRONIC CIRCUITS
NITRIDES
NITROGEN COMPOUNDS
PALLADIUM COMPOUNDS
PALLADIUM SILICIDES
PNICTIDES
REFRACTORY METAL COMPOUNDS
SILICIDES
SILICON COMPOUNDS
TANTALUM COMPOUNDS
TANTALUM NITRIDES
THIN FILMS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TUNGSTEN