Semiconductor structures and methods of forming them

Abstract

The invention provides a semiconductor structure and a formation method thereof. The formation method comprises the following steps: forming a gate medium layer on substrates of a first N region, a second N region, a first P region and a second P region and forming a first work function layer on the gate medium layer; carrying out reduction processing on the gate medium layer, under the first workfunction layer, of the first P region to increase oxygen vacancy content in the gate medium layer of the first P region; after the reduction processing, forming a second work function layer on the first work function layer of the first P region and the second P region; forming a third work function layer on the first work function layer of the second N region and the second work function layer ofthe first P region and the second P region; and forming an N-type work function layer on the first work function layer of the first N region and on the third work function layer respectively. The method reduces complexity of the formation process of the semiconductor structure, saves the process steps and reduces the number of work function layers required by the semiconductor structure.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a semiconductor structure and a forming method thereof. Background technique [0002] The main semiconductor device of an integrated circuit, especially a very large scale integrated circuit, is a metal-oxide-semiconductor field effect transistor (MOS transistor). With the continuous development of integrated circuit manufacturing technology, the technology nodes of semiconductor devices are continuously reduced, and the geometric dimensions of semiconductor structures are continuously reduced following Moore's law. When the size of the semiconductor structure is reduced to a certain extent, various secondary effects caused by the physical limit of the semiconductor structure appear one after another, and it becomes more and more difficult to scale down the feature size of the semiconductor structure. Among them, in the field of semiconductor manufacturing, t...

AI Technical Summary

Problems solved by technology

[0004] Although the introduction of a high-k metal gate can improve the electrical properties of the semiconductor structure to a certain extent, the semiconductor structure formed by the prior art is complex in process, and the number of work function layers required by the semiconductor structure is large, which is not conducive to improving the semiconductor structure formed. performance of the structure

Images