Method for fabricating semiconductor device with metal gate

Abstract

The present invention provides a method for manufacturing a semiconductor device with a metal gate. After removing the portion of the dummy gate corresponding to the PMOS transistor region or the NMOS transistor region, the method adds cleaning and forming metal on the sidewalls of the remaining dummy gate. The step of silicide can prevent the formation of a non-conductive interface layer at the contact position between the PMOS transistor metal gate and the NMOS transistor metal gate, avoiding the entire metal gate composed of the PMOS transistor metal gate and the NMOS transistor metal gate. The sheet resistance of the pole increases, and the electron movement speed in the metal gate of the PMOS transistor and the metal gate of the NMOS transistor slows down, thereby preventing the operating speed of the semiconductor device from decreasing. The metal silicide formed at the contact position between the metal gate of the PMOS transistor and the metal gate of the NMOS transistor in the present invention is conductive and will not reduce the operating speed of the semiconductor device.

Description

technical field [0001] The invention belongs to the field of semiconductor manufacturing, in particular to a method for manufacturing a semiconductor device with a metal gate. Background technique [0002] A common trend in existing integrated circuit manufacturing is to produce transistors with very small feature sizes, and most transistors include a gate dielectric layer made of silicon oxide (or silicon oxynitride, etc.) and a gate made of polysilicon. laminated structure. As the transistor size becomes smaller and smaller, there are many problems in the transistor, such as gate leakage, poly depletion, boron penetration effect, etc., which affect the integration further development of the circuit. In order to solve the above problems, a new type of transistor has been studied: it replaces the material of the gate dielectric layer from silicon oxide to a high-K dielectric layer (K ​​here refers to a dielectric constant), and the material of the gate is changed from Pol...

AI Technical Summary

Problems solved by technology

[0010] However, in practical applications, it is found that the semiconductor devices made by the above-mentioned manufacturing method have a low operating speed.

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