Method for preparing nickel silicide by laser annealing

Abstract

The invention discloses a method for preparing a nickel silicide by laser annealing. The nickel silicide is prepared by twice laser annealing processes, it is ensured that the temperatures of the twice laser annealing are kept within a certain range, and finally the nickel silicide with a relatively low resistivity can be obtained. Annealing is implemented through laser, so that compared with the traditional technology, the speed is higher, the working efficiency is greatly improved, and the production cost is reduced; and laser can be used to heat necessary positions of a silicon chip but not other positions, thereby avoiding that nickel is diffused at unnecessary positions and reacts with silicon to generate nickel silicide peaks which cause current leakage, and improving the performance of devices.

Description

technical field [0001] The invention relates to a process for forming nickel silicide in the semiconductor wafer production industry, in particular to a method for forming nickel silicide by laser annealing. Background technique [0002] As the integration of semiconductor devices continues to increase and the critical dimensions associated with these devices continue to decrease, how to manufacture semiconductor devices with low-resistance materials to maintain or reduce signal delay has become the focus of attention, while the gate conductors and The reduction of the sheet resistance and contact resistance of the source / drain region is equally important as the subsequent interconnection. Silicide and salicide materials and processes have been widely used to reduce the sheet resistance and contact resistance of gate conductors and source / drain regions of CMOS devices. [0003] Metals and alloys including titanium, cobalt and nickel have been used to form silicide layers on...

AI Technical Summary

Problems solved by technology

However, this patent also uses the traditional annealing process for annealing. Since the traditional annealing is to place the entire silicon wafer in a reaction furnace to heat all parts of the silicon wafer, it inevitably requires a large amount of energy for heating, and the annealing The speed is also slow. At the same time, because the nickel in the source and drain regions of the silicon wafer and the bottom of the gate stays at high temperature for a long time, it is easy to produce vertical diffusion or lateral diffusion, and it combines with deep Si to form a nickel silicide peak, which leads to leakage. current, which affects device performance

Images