Surface organometallic chemistry in the chemical vapor deposition of aluminum films using triisobutylaluminum: /beta/-hydride and /beta/-alkyl elimination reactions of surface alkyl intermediates

Journal Article · Wed Mar 01 04:00:00 EST 1989 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00187a016· OSTI ID:5889717

Bent, B E; Nuzzo, R G; Dubois, L H

Thermal decomposition of triisobutylaluminum (TIBA) to deposit aluminum films shows promise as a way to form conductive contacts on silicon-based electronic devices. An important step in the steady-state deposition is the reaction of TIBA with the growing aluminum surface. The authors have studied this chemistry by reacting TIBA with single-crystal Al(111) and Al(100) surfaces. A combination of effusive molecular beam scattering, thermal desorption spectroscopy, Auger electron spectroscopy, low-energy electron diffraction, high-resolution electron energy loss spectroscopy, and scanning electron microscopy was used in these studies. The authors find that TIBA decomposes on both of these aluminum surfaces above /approximately/ 470 K by /beta/-hydride elimination reactions to deposit aluminum and evolve hydrogen and isobutylene. This surface /beta/-hydride elimination reaction is the rate-determining step. The authors find that the reaction is 2-5 times faster on Al(111) than on Al(100). In the temperature range of 470-600 K, the growing film is carbon-free, crystalline, and adopts the orientation of the single-crystal substrate. At higher temperatures, the deposited aluminum contains carbon, and they present evidence that a surface /beta/-methyl elimination reaction is responsible, at least in part, for this contamination. Using the kinetic parameters determined from monolayer thermal deposition experiments for this reaction, they are able to predict the rate of steady-state aluminum deposition for TIBA pressures between 10/sup /minus/6/ and 1 Torr.

• Research Organization: AT and T Bell Labs., Murray Hill, NJ (USA)
• OSTI ID: 5889717
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 111:5; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601* -- Other Materials-- Preparation & Manufacture
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
ALUMINIUM
ALUMINIUM COMPOUNDS
AUGER ELECTRON SPECTROSCOPY
BEAMS
CHEMICAL COATING
CHEMICAL REACTION KINETICS
CHEMICAL VAPOR DEPOSITION
COHERENT SCATTERING
DATA
DEPOSITION
DESORPTION
DIFFRACTION
ELECTRON DIFFRACTION
ELECTRON MICROSCOPY
ELECTRON SPECTROSCOPY
ELEMENTS
ENERGY-LOSS SPECTROSCOPY
EQUATIONS
EXPERIMENTAL DATA
FILMS
HIGH TEMPERATURE
HYDRIDES
HYDROGEN COMPOUNDS
INFORMATION
KINETICS
METALS
MICROSCOPY
MOLECULAR BEAMS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
PREDICTION EQUATIONS
REACTION INTERMEDIATES
REACTION KINETICS
SCANNING ELECTRON MICROSCOPY
SCATTERING
SPECTROSCOPY
STEADY-STATE CONDITIONS
SURFACE COATING
SURFACES
THERMAL DEGRADATION
THIN FILMS