| CPC H01L 21/324 (2013.01) [H01L 21/76832 (2013.01); H01L 29/161 (2013.01); H01L 29/517 (2013.01); H01L 29/66545 (2013.01); H01L 29/66795 (2013.01); H01L 29/785 (2013.01)] | 17 Claims |

|
1. A semiconductor device, comprising:
a substrate that contains a semiconductive material;
a fin structure that protrudes out of the substrate, wherein the fin structure is a fin structure for a p-type FinFET transistor;
a silicon cap layer disposed on the fin structure, wherein the silicon cap layer is a single continuous structure, wherein a first segment of the silicon cap layer is disposed directly on an upper surface of the fin structure, wherein a second segment of the silicon cap layer is disposed directly on a side surface of the fin structure, and wherein the first segment and the second segment have a same material composition; and
a gate dielectric layer disposed over the silicon cap layer;
wherein:
the fin structure has a line width roughness (LWR) between about 1.7 nanometers (nm) and about 1.9 nm; or
the fin structure has a line edge roughness (LER) between about 1.5 nanometers (nm) and about 1.7 nm;
the fin structure has an average width Finwidth-average;
a ratio of LWR:Fin_width_average is in a range between about 1:4 and about 1:5; and
a ratio of LER:Fin_width_average is in a range between about 1:4 and about 1:5.
|