Method for fabricating a semiconductor device including fin relaxation, and related structures

摘要

Methods of fabricating semiconductor structures involve the formation of fins for finFET transistors having different stress/strain states. Fins of one stress/strain state may be employed to form n-type finFETS, while fins of another stress/strain state may be employed to form p-type finFETs. The fins having different stress/strain states may be fabricated from a common layer of semiconductor material. Semiconductor structures and devices are fabricated using such methods.

主权项

1. A method of fabricating a semiconductor device, comprising:
forming at least one strained first fin in a layer of strained semiconductor material overlying an insulating layer on a base substrate, the at least one strained first fin having a first length below a critical length Lc below which the strained semiconductor material of the at least one strained first fin relaxes upon subsequently conducting a heat treatment between 950° C. and 1250° C.; after forming the at least one strained first fin, conducting the heat treatment between 950° C. and 1250° C., the heat treatment causing relaxation of stress within the at least one strained first fin so as to form at least one relaxed first fin; and forming at least one strained second fin in the layer of strained semiconductor material; wherein the at least one strained second fin has a second length above the critical length Lc such that the at least one strained second fin does not relax while conducting the heat treatment between 950° C. and 1250° C., or the at least one strained second fin is formed after conducting the heat treatment.