Method of manufacturing semiconductor device
View Patent ↗To improve a semiconductor device having a nonvolatile memory. A first MISFET, a second MISFET, and a memory cell are formed, and a stopper film made of a silicon oxide film is formed thereover. Then, over the stopper film, a stress application film made of a silicon nitride film is formed, and the stress application film over the second MISFET and the memory cell is removed. Thereafter, heat treatment is performed to apply a stress to the first MISFET. Thus, a SMT is not applied to each of elements, but is applied selectively. This can reduce the degree of degradation of the second MISFET due to H (hydrogen) in the silicon nitride film forming the stress application film. This can also reduce the degree of degradation of the characteristics of the memory cell due to the H (hydrogen) in the silicon nitride film forming the stress application film.
1. A method of manufacturing a semiconductor device, comprising the steps of:
(a) providing a semiconductor substrate having a first MISFET formed in a first region, and a nonvolatile memory having a charge storage portion formed in a second region;
(b) forming a first insulating film over the first MISFET and the nonvolatile memory cell;
(c) selectively removing the first insulating film in the second region and leaving the first insulating film in the first region; and
(d) after the step (c), performing heat treatment to both the first and second regions of the semiconductor substrate, with the first insulating film in the first region, to memorize a stress in the first MISFET.
2. A method of manufacturing a semiconductor device according to claim 1 , further comprising the step of:
(e) after the step (d), removing the first insulating film in the first region.
3. A method of manufacturing a semiconductor device according to claim 2 , further comprising the step of:
(f) after the step (e), forming a silicide film over each of source/drain regions of the first MISFET or the nonvolatile memory cell formed in the semiconductor substrate made of a silicon substrate.
4. A method of manufacturing a semiconductor device according to claim 1 , wherein the first insulating film is a silicon nitride film.
5. A method of manufacturing a semiconductor device according to claim 1 , wherein the nonvolatile memory cell has a first gate electrode formed over the semiconductor substrate, and a first gate insulating film formed between the first gate electrode and the semiconductor substrate and having the charge storage portion in the inside thereof.
6. A method of manufacturing a semiconductor device according to claim 1 , further comprising the step of:
(g) after the step (a) and prior to (b), forming the second insulating film over the first MISFET and the nonvolatile memory cell.
7. A method of manufacturing a semiconductor device according to claim 6 , (h) after the step (e) and prior to the step (f), removing the second insulating film.
8. A method of manufacturing a semiconductor device according to claim 6 , wherein the second insulating film is a silicon oxide film.