Patent ID: 11373910

Abstract:
A method of forming a semiconductor device including a fin field effect transistor (FinFET), the method includes forming a first sacrificial layer over a source/drain structure of a FinFET structure and an isolation insulating layer. The first sacrificial layer is patterned, thereby forming an opening. A first liner layer is formed on the isolation insulating layer in a bottom of the opening and on at least side faces of the patterned first sacrificial layer. After the first liner layer is formed, forming a dielectric layer in the opening. After the dielectric layer is formed, removing the patterned first sacrificial layer, thereby forming a contact opening over the source/drain structure. A conductive layer is formed in the contact opening. The FinFET is an n-type FET, and the source/drain structure includes an epitaxial layer made of Si1-y-a-bGeaSnbM2y, wherein 0<a, 0<b, 0.01≤(a+b)≤0.1, 0.01≤y≤0.1, and M2 is P or As.