Semiconductor device and its manufacturing method

Abstract

A semiconductor component includes a substrate, a grid structure, a gapping place wall, and a first polysilicon germanium layer with boron dope and a second polysilicon germanium layer. The substrate has two opening, and the grid structure are placed at the substrate between two openings. The gapping wall is configured at the lateral wall of the grid structure, and situated above the two openings. In addition, first polysilicon germanium layer is configured at the surface of the two opening of the substrate, moreover second polysilicon germanium layer is configured at first polysilicon germanium layer, and the top of second polysilicon germanium layer is higher than the surface of the substrate. Wherein, boron concentration of first polysilicon germanium layer is lower than that of second polysilicon germanium layer.

Description

technical field [0001] The invention relates to an element structure of an integrated circuit, and in particular to a semiconductor element and a manufacturing method thereof. Background technique [0002] For silicon metal oxide semiconductor transistor devices, when the gate length is reduced to a deep sub-micron range, better device performance can be obtained because the carrier transit time decreases as the channel length shortens. However, there are still many technical difficulties to be overcome in the development of this kind of process. [0003] At present, in order to obtain better device performance, metal-oxide-semiconductor transistors in which source / drain regions are fabricated by silicon germanium technology are being actively developed. SiGe material can be selectively grown in the source / drain regions, and SiGe material can be selectively etched relative to silicon and silicon oxide. [0004] Usually, a high concentration of boron (boron) is doped into t...

AI Technical Summary

Problems solved by technology

However, the boron doped in the polysilicon germanium layer will inevitably diffuse out

If the boron dopant diffuses vertically, the junction depth will be too deep, which will easily cause problems such as electrical breakdown (punchthrough) effect; if the boron dopant diffuses laterally, it will easily cause short channel effect, which will affect the Component performance

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