Nonvolatile memory and nonvolatile memory manufacturing method
View Patent ↗A nonvolatile memory device includes source and drain regions formed in a semiconductor substrate, and an insulating film formed on a channel region between the source region and the drain region in the semiconductor substrate. The nonvolatile memory device also includes a dielectric film formed above the channel region to store electric charge, and a control gate formed on the dielectric film. Compressive stress in the channel region is equal to or less than 50 MPa.
1. A nonvolatile memory device comprising:
source and drain regions formed in a semiconductor substrate;
an insulating film formed on a channel region between said source region and said drain region in said semiconductor substrate;
a dielectric film formed above said channel region to store electric charge; and
a control gate formed on said dielectric film,
wherein compressive stress in said channel region is equal to or less than 50 MPa.
2. The nonvolatile memory device according to claim 1 , wherein tensile stress in said channel region is equal to or less than 50 MPa.
3. The nonvolatile memory device according to claim 1 , wherein said control gate has a laminate structure in which a conductive semiconductor film and a metal film are laminated in this order from a side of said dielectric film.
4. The nonvolatile memory device according to claim 3 , wherein said metal film contains at least a material selected from the group consisting of tungsten, tantalum, molybdenum, tungsten nitride, tantalum nitride and molybdenum nitride.
5. The nonvolatile memory device according to claim 1 , wherein at least a part of said semiconductor substrate has a laminate structure in which a silicon region and a silicon germanium region are laminated in this order from a side of a surface of said semiconductor substrate.
6. The nonvolatile memory device according to claim 1 , wherein at least one of said source region and said drain region contains one of a carbon added silicon region and a carbon added silicon germanium region.
7. The nonvolatile memory device according to claim 1 , wherein said dielectric film comprises a semiconductor thin film.
8. The nonvolatile memory device according to claim 1 , wherein said dielectric film comprises a charge storage insulating film containing electric charge trap centers.
9. The nonvolatile memory device according to claim 8 , wherein said charge storage insulating film is formed of a material selected from the group consisting of silicon nitride, aluminum oxide, aluminum oxynitride, hafnium oxide, hafnium oxynitride, silicon hafnium oxide, silicon hafnium oxynitride, zirconium oxide, zirconium oxynitride, silicon zirconium oxide and silicon zirconium oxynitride.
10. The nonvolatile memory device according to claim 1 , wherein said dielectric film comprises a charge storage insulating film in which semiconductor particles are dispersed.
11. The nonvolatile memory device according to claim 1 , wherein said dielectric film comprises a ferroelectric film.
12. The nonvolatile memory device according to claim 1 , wherein said dielectric film has a laminate structure in which a metal film and a ferroelectric film are laminated in this order from a side of said insulating film.
13. The nonvolatile memory device according to claim 1 , further comprising:
a first interlayer insulating film formed to cover said insulating film and said control gate.
14. The nonvolatile memory device according to claim 13 , wherein said first interlayer insulating film has tensile stress.
15. The nonvolatile memory device according to claim 13 , wherein said first interlayer insulating film is formed from at least a film selected the group consisting of a SiN film, a SiON film, a SiCN film, an AlO film and an AlSiN film.
16. The nonvolatile memory device according to claim 13 , further comprising:
sidewall insulating films formed to cover side surfaces of said dielectric film and said control gate and to contact said insulating film at a bottom portion of said sidewall insulating films,
wherein said sidewall insulating film comprises:
a first insulating film formed parallel to said insulating film; and
a second insulating film parallel to said side surfaces, and
said first insulating film has tensile stress.
17. The nonvolatile memory device according to claim 16 , wherein said first insulating film contains at least one of a SiN film, a SiON film, a SiCN film, an AlO film and an AlSiN film.
18. The nonvolatile memory device according to claim 1 , further comprising:
device isolation sections formed in said semiconductor substrate.
19. The nonvolatile memory device according to claim 18 , wherein said device isolation section comprises a trench groove which contains a silicon nitride film.
20. A nonvolatile memory device comprising:
source and drain regions formed in a semiconductor substrate;
an insulating film formed on a channel region between said source region and said drain region in said semiconductor substrate;
a storage node formed above said channel region to store electric charge; and
a control gate formed on said dielectric film,
wherein compressive stress in said channel region is equal to or less than 50 Mpa.