Semiconductor device and manufacturing method therefor

Abstract

A semiconductor device is provided. The semiconductor device includes a semiconductor substrate including a conducting layer, a first insulating film formed on the semiconductor substrate and having a via hole formed therein, a lower barrier film formed on an inside wall of the via hole, a first metal wiring formed on the lower barrier film, a second insulating film formed on the first metal wiring and the first insulating film, the second insulating film being provided with a trench which has a width greater than a width of the via hole, an upper barrier film formed on a lower surface of the trench, a second metal wiring formed on the upper barrier film, and a sidewall barrier film formed on sidewalls of the upper barrier film and the second metal wiring. The sidewall barrier film has an L-shaped mirror-symmetrical structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above features and advantages will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a sectional view illustrating a structure of a semiconductor device consistent with the present invention; and

FIGS. 2 to 11 are views illustrating a method for manufacturing a semiconductor device in a sequence of manufacturing processes consistent with the present invention.

Claims

1. A semiconductor device comprising: a semiconductor substrate including a conducting layer;a first insulating film formed on the semiconductor substrate and having a via hole formed therein;a lower barrier film formed on an inside wall of the via hole;a first metal wiring formed on the lower barrier film;a second insulating film formed on the first metal wiring and the first insulating film, the second insulating film being provided with a trench which has a width greater than a width of the via hole;an upper barrier film formed on a lower surface of the trench;a second metal wiring formed on the upper barrier film; anda sidewall barrier film formed on sidewalls of the upper barrier film and the second metal wiring, wherein the sidewall barrier film has an L-shaped mirror-symmetrical structure.

2. The semiconductor device as claimed in claim 1, wherein the first insulating film has a thickness of at least 1,000 Å.

3. The semiconductor device as claimed in claim 1, wherein the first insulating film is composed of a material selected from the group consisting of FSG(fluoride-doped silicate glass), PSG(phosphorous-doped silicate glass), USG(undoped silicate glass), BPSG(boron phosphorous doped silicate glass) or silicon oxide material.

4. A method of manufacturing a semiconductor device comprising: forming a first insulating film on a semiconductor substrate;embedding a first metal wiring in the first insulating film;forming a first photosensitive film on the first insulating film, the first photosensitive film having a first trench for exposing the first metal wiring and a portion of the first insulating film;forming a second barrier film on a resulting upper structure of the semiconductor substrate;forming a metal thin film on the second barrier film;forming a second metal wiring by removing the first photosensitive film;forming a second photosensitive film on the first insulating film, wherein a region corresponding to the second metal wiring serves as a second trench;forming a third barrier film on a resulting upper structure of the semiconductor substrate;removing the second photosensitive film; andforming a second insulating film on the first insulating film and the second metal wiring.

5. The manufacturing method as claimed in claim 4, further comprising the step of hardening an outer surface of the first photosensitive film prior to the step of forming the second barrier film.

6. The manufacturing method as claimed in claim 4, further comprising the step of hardening an outer surface of the second photosensitive film prior to the step of forming the third barrier film.

7. The manufacturing method as claimed in claim 5, comprising hardening an outer surface of the first photosensitive film by immersion in trichloroethylene (TCE) for a predetermined amount of time.

8. The manufacturing method as claimed in claim 6, comprising hardening an outer surface of the second photosensitive film by immersion in trichloroethylene (TCE) for a predetermined amount of time.

9. The manufacturing method as claimed in claim 4, comprising removing the second barrier film and the metal thin film when the first photosensitive film is removed.

10. The manufacturing method as claimed in claim 4, comprising removing a portion of the third barrier film positioned on the second photosensitive film when the second photosensitive film is removed.

11. The manufacturing method as claimed in claim 4, where the widths of the first and the second trenches are tapered from their lower potions to their upper portions.

12. The manufacturing method as claimed in claim 4, wherein embedding the first metal comprises: forming a first insulating film having via holes on the semiconductor substrate;forming a first barrier film on an inside surface of the via holes;forming a metal layer on the first barrier film; and planarizing the metal layer.

13. The manufacturing method as claimed in claim 4, further comprising the step of planarizing the second insulating film.