Oxidation of hydrogen doped tantalum films on silicon

Journal Article · Thu May 01 04:00:00 EDT 1986 · J. Vac. Sci. Technol., B; (United States)

DOI:https://doi.org/10.1116/1.583602· OSTI ID:5851745

Ohfuji, S; Hashimoto, C

Hydrogen doping of Ta films before thermal oxidation affects the dc leakage current in oxidized Ta films. Metal-insulator-semiconductor (MIS) capacitors of Al/Ta/sub 2/O/sub 5/ (40 nm thick)/Si-substrate structures have been prepared for the electrical measurements. The Ta films were reactively sputtered on p-type Si substrates in a mixture of Ar and H/sub 2/ gases suitable for hydrogen doping. The hydrogen doping was found to be effective in reducing the leakage current in the Ta/sub 2/O/sub 5/ films to be less than 10/sup -3/ times that of undoped films, especially after low temperature oxidation at 400 /sup 0/C. Secondary ion mass spectrometry (SIMS) analysis showed that the incorporation in the Ta/sub 2/O/sub 5/ films of Si from the substrate was decreased by the presence of hydrogen during sputtering. A possible explanation for the reduction of leakage current caused by hydrogen doping is that the prevention of Si entry into Ta/sub 2/O/sub 5/ films reduces the density of oxygen vacancies induced by unsaturated SiO/sub x/(x<2). This is thought to suppress the Poole--Frenkel-type conduction in the Ta/sub 2/O/sub 5/ films.

• Research Organization: NTT Atsugi Electrical Communication Laboratories, 3-1, Morinosato Wakamiya, Atsugi-shi, Kanagawa Prefecture, 243-01 Japan
• OSTI ID: 5851745
• Journal Information: J. Vac. Sci. Technol., B; (United States), Journal Name: J. Vac. Sci. Technol., B; (United States) Vol. 4:3; ISSN JVTBD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105* -- Metals &amp; Alloys-- Corrosion &amp; Erosion
360204 -- Ceramics
Cermets
&amp; Refractories-- Physical Properties
ALUMINIUM
CHALCOGENIDES
CHEMICAL REACTIONS
CRYSTAL DEFECTS
CRYSTAL DOPING
CRYSTAL STRUCTURE
CURRENTS
DATA
ELECTRIC CURRENTS
ELEMENTS
EXPERIMENTAL DATA
INFORMATION
LEAKAGE CURRENT
METALS
NUMERICAL DATA
OXIDATION
OXIDES
OXYGEN COMPOUNDS
POINT DEFECTS
REFRACTORY METAL COMPOUNDS
SEMIMETALS
SILICON
TANTALUM
TANTALUM COMPOUNDS
TANTALUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
VACANCIES