TWO-DIMENSIONAL CONDENSATION FOR UNIAXIALLY STRAINED SEMICONDUCTOR FINS

摘要

Techniques are disclosed for enabling multi-sided condensation of semiconductor fins The techniques can be employed, for instance, in fabricating fin-based transistors. In one example case, a strain layer is provided on a bulk substrate. The strain layer is associated with a critical thickness that is dependent on a component of the strain layer, and the strain layer has a thickness lower than or equal to the critical thickness. A fin is formed in the substrate and strain layer, such that the fin includes a substrate portion and a strain layer portion. The fin is oxidized to condense the strain layer portion of the fin, so that a concentration of the component in the strain layer changes from a pre-condensation concentration to a higher post-condensation concentration, thereby causing the critical thickness to be exceeded.

主权项

1. A fin-based transistor device, comprising:
a silicon germanium layer provided on a silicon bulk substrate; and a fin formed in the substrate and silicon germanium layer, such that the fin includes a silicon bulk substrate portion and a silicon germanium layer portion, the silicon germanium layer portion having an upper surface and sidewall surfaces around an inner portion, wherein the upper surface and sidewall surfaces comprise a higher concentration of germanium than the inner portion, the silicon germanium layer portion having an uppermost lateral thickness less than a lateral thickness of the silicon germanium layer portion where the silicon germanium layer portion contacts the silicon bulk substrate portion.