Semiconductor device and method of fabricating the same
A semiconductor device includes a semiconductor substrate, an ONO film that is provided on the semiconductor substrate and has a contact hole, and an interlayer insulating film that is provided directly on the ONO film and contains phosphorus. The interlayer insulating film contains 4.5 wt % of phosphorus or more in an interface portion that interfaces with the ONO film. The interlayer insulating film comprises a first portion that contacts the ONO film, and a second portion provided on the first portion. The first portion has a phosphorus concentration more than that of the second portion.
1 . A semiconductor device comprising:
a semiconductor substrate;
an ONO film that is provided on the semiconductor substrate and has a contact hole; and
an interlayer insulating film that is provided on the ONO film and includes first and second portions;
wherein the first portion comprises a PSG film that is provided directly on the ONO film and has a phosphorus concentration in the range of 4.5 wt % to 10.0 wt %; and
wherein the second portion comprises a BPSG film that is provided on the first portion and has a total of a phosphorus concentration and a boron concentration equal to or less than 10.0 wt %.
2 . The semiconductor device as claimed in claim 1 , further comprising a gate electrode provided on the ONO film, wherein the interlayer insulating film is provided directly on the gate electrode.
3 . The semiconductor device as claimed in claim 1 , further comprising a gate electrode provided on the ONO film, wherein the interlayer insulating film is in contact with a silicide region formed on top of the gate electrode.
4 . (canceled)
5 . (canceled)
6 . The semiconductor device as claimed in claim 1 , wherein the first portion has a phosphorus concentration more than that of the second portion.
7 . (canceled)
8 . The semiconductor device as claimed in claim 1 wherein the interlayer insulating film is an oxide film.
9 . The semiconductor device as claimed in claim 1 wherein the interlayer insulating film is one of a CVD oxide film and a SOD (Spin On Dielectric) film.
10 . The semiconductor device as claimed in claim 1 wherein the interlayer insulating film is one of a TEOS oxide film and a HDP oxide film.
11 . A method of fabricating a semiconductor device comprising the steps of:
forming an ONO film on a semiconductor substrate in which a diffused region is formed;
forming an interlayer insulating film containing phosphorus on the ONO film;
forming a contact hole in the interlayer insulating film and the ONO film; and
forming a metal interconnection line on the interlayer insulating film, the metal interconnection line contacting the diffused region via the contact hole, wherein the step of forming the interlayer insulating film includes the steps of:
forming a first portion of the interlayer insulating film comprising a PSG film provided directly on the ONO film and containing phosphorus in the range of 4.5 wt % to 10.0 wt %; and
forming a second portion of the interlayer insulating film comprising a BPSG film provided on the first portion and containing a total of a phosphorus concentration and a boron concentration equal to or less than 10.0 wt %.
12 . (canceled)