Semiconductor device and method for manufacturing the same

摘要

A method for manufacturing a semiconductor device comprises forming a first layer on an impurity diffusion region in a semiconductor substrate by a selective epitaxial growth method, forming a second layer on the first layer by the selective epitaxial growth method, forming a contact hole penetrating an interlayer insulating film in a thickness direction thereof and reaching the second layer, and filling a conductive material into the contact hole to form a contact plug including the first and second layers and the conductive material.

主权项

1. A semiconductor device comprising:
a semiconductor substrate; a diffusion layer formed in the semiconductor substrate as a source/drain region of a field effect transistor; a first epitaxial layer formed on the diffusion layer, the first epitaxial layer comprising a first bottom surface in contact with the diffusion layer, and a first top surface; a second epitaxial silicon layer formed on the first epitaxial layer, the second epitaxial silicon layer comprising a second bottom surface which is in contact with the first top surface, and a second top surface; and a contact plug on the second epitaxial silicon layer, the contact plug being in contact with the second top surface of the second epitaxial silicon layer; the first epitaxial layer including a first side surface having an upper end; and the second epitaxial silicon layer including a second side surface projecting from the upper end of the first side surface of the first epitaxial layer so that a step is provided between the first side surface of the first epitaxial layer and the second side surface of the second epitaxial silicon layer.