METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE

摘要

A method of manufacturing a semiconductor device is provided. The method includes the following steps. A substrate including a first transistor having a first conductivity type, a second transistor having a second conductivity type and a third transistor having the first conductivity type is formed. An inner-layer dielectric layer is formed on the substrate, and includes a first gate trench corresponding to the first transistor, a second gate trench corresponding to the second transistor and a third gate trench corresponding to the third transistor. A work function metal layer is formed on the inner-layer dielectric layer. An anti-reflective layer is coated on the work function metal layer. The anti-reflective layer on the second transistor and on the top portion of the third gate trench is removed to expose the work function metal layer. The exposed work function metal layer is removed.

主权项

1. A method of manufacturing a semiconductor device, comprising:
forming a substrate including a first transistor having a first conductivity type, a second transistor having a second conductivity type and a third transistor having the first conductivity type, wherein the first conductivity type and the second conductivity type are complementary; forming an inner-layer dielectric layer on the substrate, wherein the inner-layer dielectric layer comprises a first gate trench corresponding to the first transistor, a second gate trench corresponding to the second transistor and a third gate trench corresponding to the third transistor; forming a work function metal layer on the inner-layer dielectric layer; coating an anti-reflective layer on the work function metal layer to fill the first gate trench, the second gate trench and the third gate trench; removing a portion of the anti-reflective layer that is filled in the second gate trench to expose a portion of the work function metal layer and to leave a first capping portion and a second capping portion of the anti-reflective layer with different levels respectively in the first gate trench and the third gate trench; and removing the exposed portions of the work function metal layer to form a U-shaped work function metal layer in the third gate trench.