Method of forming wire interconnection wire
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorTokuhiko Tamaki
Life of this patent
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Abstract
A silicon substrate on which a silicon dioxide film having a groove is formed is placed on a sample stage disposed in a vacuum chamber. Subsequently, a titanium film and a tungsten film are deposited sequentially on the silicon dioxide film. The surface of the tungsten film is nitrided by using a plasma under the pressure maintained at 10 Pa or higher inside the vacuum chamber, so as to form a tungsten nitride film. After a copper film is deposited on the tungsten nitride film, the portions of the titanium film, tungsten film, tungsten nitride film, and copper film located outside the groove are removed, thus forming a buried interconnecting wire made of copper.
Claims6
A method of forming an interconnect, comprising the steps of:
- forming a first recessed portion in an insulating film deposited on a semiconductor substrate;
- forming a first conductive film on each of a bottom face and side faces of said first recessed portion by chemical vapor deposition, said first conductive film comprising a conductive material and having a second recessed portion in a position corresponding to said first recessed portion of said insulating film;
- forming a second conductive film in an upper portion of each of a bottom face and side faces of said second recessed portion of said first conductive film by performing plasma nitriding on a surface of said first conductive film with said semiconductor substrate being held in a vacuum chamber maintained at a pressure of 10 Pa or higher, said second conductive film comprising a nitride of said conductive material and having a third recessed portion in a position corresponding to said second recessed portion of said first conductive film;
- forming a metal film by depositing a metal on said second conductive film and said insulating film such that said metal is filled in said third recessed portion of said second conductive film, said metal film comprising said metal;
- and
- forming an interconnect formed of said metal in said third recessed portion of said second conductive film by removing a portion of said metal film which is located above said insulating film,
- wherein the chemical vapor deposition in the step of forming said first conductive film is performed at a temperature within such a range as to suppress crystallization of said conductive material and make at least a part thereof amorphous.
Dependencies are inferred from the claim text.