Semiconductor device and fabrication method thereof
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorYoshihiro Kusumi
Life of this patent
Estimating the term…
Abstract
A connection hole stopper film such as the silicon nitride film is formed to directly cover a lower interconnection. A lower interlayer insulation film is formed to directly cover that connection hole stopper film. An upper interlayer insulation film differing in etching property from the lower interlayer insulation film is formed to directly cover the lower interlayer insulation film. The upper interlayer insulation film is subjected to anisotropic etching, whereby an upper interconnection trench is formed. An upper interconnection is formed in that upper interconnection trench. A semiconductor device is obtained reduced in capacitance between interconnections and variation in the interconnection resistance.
Claims8
A semiconductor device comprising:
- a semiconductor substrate having a main surface;
- a first interconnection formed on said semiconductor substrate;
- an etching stopper film formed to directly cover said first interconnection;
- a first insulation film formed to directly cover said etching stopper film;
- a second insulation film formed to directly cover said first insulation film;
- an interconnection trench formed in said second insulation film, and exposing an upper surface of said first insulation film;
- and
- a second interconnection formed in said interconnection trench, wherein said first and second insulation films have different anisotropic etching rates such that said second insulation film can be etched without substantially etching the first insulation film.
A semiconductor device comprising:
- a semiconductor substrate having a main surface;
- a first interconnection formed on said semiconductor substrate;
- a conductive etching stopper film formed to directly cover said first interconnection;
- a first insulation film formed to directly cover said conductive etching stopper film;
- a second insulation film formed to directly cover said first insulation film, and having an etching property differing from the etching property of said first insulation film;
- a third insulation film formed to directly cover said second insulation film;
- an interconnection trench formed in said third insulation film, and exposing an uppermost surface of said second insulation film;
- and
- a second interconnection formed in said interconnection trench.
Dependencies are inferred from the claim text.