US 8,076,192 B2 · Method of manufacturing a semiconductor device

Abstract

Provided is a manufacturing method of a semiconductor device, which comprises forming a film stack of a gate insulating film, a charge storage film, insulating film, polysilicon film, silicon oxide film, silicon nitride film and cap insulating film over a semiconductor substrate; removing the film stack by photolithography and etching from a low breakdown voltage MISFET formation region and a high breakdown voltage MISFET formation region; forming gate insulating films, polysilicon film and cap insulating film over the semiconductor substrate, forming a gate electrode in the low breakdown voltage MISFET formation region and high breakdown voltage MISFET formation region, and then forming a gate electrode in a memory cell formation region. By the manufacturing technology of a semiconductor device for forming the gate electrodes of a first MISFET and a second MISFET in different steps, the present invention makes it possible to provide the first MISFET and the second MISFET each having improved reliability.

Claims21

Dependent claims

A manufacturing method of a semiconductor device for forming a first MISFET over a first region of a semiconductor substrate and a second MISFET over a second region of the semiconductor substrate, which comprises the steps of:

(a) forming a first insulating film over the first region and the second region;
(b) forming a first metal film over the first insulating film;
(c) removing the first metal film and the first insulating film formed over the second region;
(d) after the step (c), forming a second insulating film over the second region and the first metal film over the first region;
(e) forming a second metal film over the second insulating film, wherein a second material composing the second metal film is different from a first material composing the first metal film;
(f) patterning the second metal film and the second insulating film formed over the second region to form a second gate electrode and a second gate insulating film of the second MISFET;
and
(g) after the step (f), patterning the first metal film and the first insulating film formed over the first region to form a first gate electrode and a first gate insulating film of the first MISFET.

5 more elements

Dependencies are inferred from the claim text.

Method of manufacturing a semiconductor device

Life of this patent

Method of manufacturing a semiconductor device

Life of this patent

Abstract

Claims21