Method of making a semiconductor device with residual amine group free multilayer interconnection
The present invention provides a semiconductor device that can restrict the dissolution hindering phenomenon in a chemically amplified resist film. More specifically, after the formation of a contact pattern on a semiconductor substrate, a wiring pattern is formed on the contact pattern. A SiC film, a first SiOC film, a SiC film, a second SiOC film, a USG film as a diffusion preventing film, and a silicon nitride film as a reflection preventing film, are formed on the wiring pattern. A dual damascene structure is then formed using the chemically amplified resist film and another chemically amplified resist film. In this manner, the N 2 gas generated during the formation of the silicon nitride film as a reflection preventing film can be prevented from diffusing into the second SiOC film formed under the silicon nitride film. Accordingly, the reaction of the N 2 gas with the H group contained in the second SiOC film and the generation of an amine group such as NH in the second SiOC film can be prevented. Thus, the dissolution hindering phenomenon in the chemically amplified resist film can be avoided.
1 . A method of manufacturing a semiconductor device having a multilayered interconnection structure,
the method comprising the steps of:
forming an interlayer insulating film made of an oxide film containing carbon on a substrate;
forming an insulating film on the interlayer insulating film, using a gas not containing nitrogen;
forming a reflection preventing film on the insulating film;
forming a chemically amplified resist film on the reflection preventing film; and
patterning the chemically amplified resist film.
2 . A method of manufacturing a semiconductor device, comprising the steps of:
forming a first interlayer insulating film on a substrate;
forming a second interlayer insulating film made of a silicon oxide film containing carbon on the first interlayer insulating film;
forming an insulating film on the second interlayer insulating film, using a gas not containing nitrogen;
forming a reflection preventing film on the insulating film;
forming a first opening through the first interlayer insulating film and the second interlayer insulating film; and
forming a second opening through the second interlayer insulating film, with a chemically amplified resist film formed on the reflection preventing film being a mask.
3 . The method as claimed in claim 2 , wherein the first interlayer insulating film and the second interlayer insulating film are made of silicon oxide films containing carbon.
4 . The method as claimed in claim 2 , wherein the silicon oxide film containing carbon is a porous film.
5 . The method as claimed in claim 2 , wherein the insulating film is formed by a CVD method using a TEOS gas.
6 . The method as claimed in claim 2 , wherein the insulating film is formed with a SiC film using tetramethylsilane (Si(CH 3 ) 4 ) and CO 2 as growth gases.
7 . The method as claimed in claim 2 , wherein the insulating film is formed with a PSG film.
8 . The method as claimed in claim 2 , wherein the insulating film is formed with a SiOC film having a higher density than the first and second interlayer insulating films, using tetramethylcyclotetrasiloxane (CH 3 (H)SiO 4 ), CO 2 , and O 2 , as growth gases.
9 . The method as claimed in claim 2 , wherein the reflection preventing film is formed with a SiN film using SiH 4 , NH 3 , and N 2 as growth gases.
10 . The method as claimed in claim 2 , wherein the insulating film has a film thickness of 100 nm or smaller.
11 . The method as claimed in claim 2 , wherein the insulating film has a film thickness of 30 nm or smaller.