SEMICONDUCTOR DEVICE AND SEMICONDUCTOR DEVICE MANUFACTURING METHOD

• Main Authors: SAMESHIMA KATSUMI, NAKAO YUICHI, NAKAGAWA RYOSUKE, YAMAHA TAKAHISA, KAGEYAMA SATOSHI
• Format: Patent
• Language: English
• Published: 11.02.2010
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

A semiconductor device according to the present invention includes: a semiconductor substrate; a first copper interconnection provided on the semiconductor substrate; an insulating layer provided over the first copper interconnection and having a hole extending therethrough to the first copper interconnection; a barrier layer composed of a tantalum-containing material and covering at least a sidewall of the hole and a part of the first copper interconnection exposed in the hole; and a second copper interconnection provided in intimate contact with the barrier layer and electrically connected to the first copper interconnection via the barrier layer; wherein the barrier layer has a nitrogen concentration profile such that the concentration of nitrogen contained in the material varies to be lower in a boundary portion of the barrier layer adjacent to the first copper interconnection and in a boundary portion of the barrier layer adjacent to the second copper interconnection and higher in an intermediate portion of the barrier layer defined between the boundary portions.