Small Size Silicide Technology Optimization And Defects In Semiconductor Device Improvement Research

Metal silicides play a very important role in semiconductor manufacturing technology. Metal silicides are used as a contactor between the CMOS electrode and metal lines. The technology of self-aligned silicide is one of the most important processes in VLSI manufacturing now. The resistance has been decrease between semiconductors and metal by silicide. at the same time, RC delay in integrated circuit is shorten by metal silicides technology. With the development of semiconductor devices’technology, in order to match the down-scaling device width size. Process of metal silicide is continual improving. For45nm and the following technologies node of the semiconductor technology, Nickel silicide is becoming the mainstream. Relative to other materials which were used before, Nickel silicide has little width effect, and less consumption of silicon, etc.Compared the silicides which were used before, a lot of advantages has been found by Nickel silicide. But Nickel silicide gives process control and integration strict requirements. High sensitive of temperature, limited the following process temperature after silicide completed. Process thermal budget is must be exact than before. Another challenging of Nickel silicide process integration is the increasing current of contact interface. The root cause is the roughness silicon before silicide reaction. The wafer pre-clean includes silicon surface which is contacted to Nickel, must be clean clearly, softly and carefully. poor clean process of silicon may cause piping defect, and it kill IC yield finally. The thesis is focus on the new technology of silicon surface pre-clean. and improvements of Nickel silicide piping defect by dosing Pt element in Nickel alloy which is use to Form the silicides.