AVS 46th International Symposium
    Electronic Materials and Processing Division Wednesday Sessions
       Session EM-WeP

Paper EM-WeP6
Formation of Ni-silicides on (001)Si with a Thin Interposing Pt Layer

Wednesday, October 27, 1999, 5:30 pm, Room 4C

Session: Poster Session
Presenter: L.-W. Cheng, National Tsing Hua University, Taiwan, R.O.C.
Authors: L.-W. Cheng, National Tsing Hua University, Taiwan, R.O.C.
S.-L. Cheng, National Tsing Hua University, Taiwan, R.O.C.
L.-J. Chen, National Tsing Hua University, Taiwan, R.O.C.
Correspondent: Click to Email
As devices dimensions scale down to deep sub-micron regime, a linewidth dependence of sheet resistance was observe for TiSi@sub 2@. Among metal silicides, low resistivity NiSi is currently one of the two most promising silicides to replace TiSi@sub 2@ for the self-aligned technology of ULSI. NiSi possesses low resistivity, low silicon consumption, low processing temperature and relative insensitivity to the linewidth of the silicide. Previous works showed that the process window of NiSi can be extended to higher temperatures by nitrogen ion implantation. In the present work, the formation of Ni-silicides on (001)Si with a thin interposing Pt layer have investigated. TEM, XRD, SIMS and four point probe were used to analyze the characteristics of nickel silicide thin films. Pt addition was found to retard significantly the formation of nickel silicides on (001)Si. The process window of NiSi was extended to a higher temperature and the sheet resistance maintained the same low level in a wide temperature range. NiSi was observed to be the dominant phase for the samples annealed at 400-800 0C with a thin interposing Pt layer. Since nickel atoms are the dominant diffusing species in the Ni/Si binary system, the results implied that the diffusion of nickel atoms through Ni/Si interface is retarded by the presence of a thin interposing Pt layer.