Method for fabricating MOS transistor

A method for fabricating metal-oxide semiconductor (MOS) transistor, comprising:

• providing a semiconductor substrate, wherein the semiconductor substrate comprises a source/drain region thereon;
• forming a Ni—Pt layer and a barrier layer on the source/drain region;
• performing a first rapid thermal process to form part of the Ni—Pt layer and the source/drain region into a silicide;
• removing un-reacted nickel and barrier layer from the first thermal process;
• performing a second rapid thermal process to drive-in platinum from a surface of the silicide into the silicide;
• removing un-reacted platinum from the second rapid thermal process;
• and
• performing a third rapid thermal process for lowering the resistance of the silicide.