Full silicidation process for making CoSi2 on SiO2

Applied Physics Letters (Impact Factor: 3.3). 04/2004; 84(17). DOI: 10.1063/1.1728299
Source: OAI


A silicidation process was developed to produce high-quality CoSi2 directly on SiO2, which can be used for metal gates of metal-oxide-semiconductor field-effect transistors (MOSFETs). Normally, the formation of a CoSi2 layer on SiO2 is very difficult because of the requirement for an exact Co/Si thickness ratio. In our process, an additional Si layer was deposited after the first rapid thermal processing (RTP) at 500 degreesC and selective etching of the unreacted Co. The additional Si layer provided a Si supply for the second RTP at a higher temperature. This method allows the Co layer thickness to be varied over a fairly large range, and in addition, the microstructure of the silicide layer and the CoSi2/SiO2 interface were substantially improved. (C) 2004 American Institute of Physics.

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