FINFET manufacturing method

Abstract

A FINFET manufacturing method, comprising: a. providing a semiconductor substrate, and forming a first fin on the substrate; b. covering the first fin with a mask layer; c. forming a punch-through barrier layer in the semiconductor substrate; d. etching the punch-through barrier layer and a part of the semiconductor substrate in sequence by taking the first fin and the mask layer as masks, expanding the first fin into a second fin, and removing the masks; and e. forming a trench isolation structure on the semiconductor substrate, forming a source-drain region on the second fin, and forming a gate laminate and an interlayer dielectric layer on the semiconductor substrate and the second fin. A punch-through barrier layer is formed by means of lateral scattering, and at the same time, an isolation layer is formed after the punch-through barrier layer is formed using a substrate material as a carrier of scattering impurities, thereby effectively solving the problems of impurities and damage introduced during lateral scattering, and greatly improving the performance of a device.

Description

technical field [0001] The invention relates to a method for manufacturing a semiconductor device, in particular to a method for manufacturing a FINFET. technical background [0002] As the size of the semiconductor device is scaled down, there arises a problem that the threshold voltage decreases with the decrease of the channel length, that is, a short channel effect is generated in the semiconductor device. To meet the challenges from semiconductor design and manufacturing, led to the development of Fin Field Effect Transistor, or FinFET. [0003] Channel punch-through effect (Channelpunch-througheffect) is a phenomenon that the source junction and the depletion region of the drain junction of the field effect transistor are connected. When the channel is penetrated, the potential barrier between the source and the drain is significantly reduced, and a large number of carriers are injected from the source to the channel, and drift through the space charge region between ...

AI Technical Summary

Problems solved by technology

This method effectively reduces the defects and impurities introduced in the channel by direct ion implantation, and improves the performance of the device. However, due to the relatively large ion implantation energy and dose required to form scattering, this method will inevitably Dielectric properties of the damage-forming isolation layer

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