Semiconductor device and manufacturing method therefor
OwnerMika Ebiharainventor
Life of this patent
Estimating the term…
Abstract
The present invention has an object to provide a MOS type transistor with a simple process, in which a high concentration junction can be stably formed so shallowly as to prevent a high concentration region constituting a drain/source region from extending beyond a contact hole due to a production variation, which cannot be attained by a conventional MOS type transistor of an LDD structure. The present invention having the following feature. That is, in forming the contact hole of the MOS type transistor, a nitride film is used as an etch-stop film to keep an Si substrate from being overetched. By using the contact hole as a mask, ion implantation is carried out to form the high concentration diffusion region constituting the source/drain region.
Claims7
A semiconductor device comprising:
- a field oxide film formed on a semiconductor substrate of one conductivity type;
- a gate electrode formed through a gate oxide film on the semiconductor substrate of one conductivity type, which is surrounded by the field insulation film;
- a low concentration source/drain region of a reverse conductivity type formed in a region surrounded by the field oxide film and the gate electrode;
- an interlayer film for electrically isolating the gate electrode and the low concentration source/drain region of the reverse conductivity type from a wiring formed thereon;
- a contact hole formed in the interlayer film for electrically connecting between the wiring, and the gate electrode and the low concentration source/drain region of the reverse conductivity type;
- a nitride film formed for preventing the semiconductor substrate of one conductivity type from being overetched when forming the contact hole in the interlayer film;
- and
- a high concentration diffusion layer of a reverse conductivity type selectively formed only in the low concentration source/drain region of the reverse conductivity type where the contact hole is formed.
A manufacturing method for a MOS type transistor comprising:
- forming a gate insulating film on a surface of a semiconductor substrate;
- forming a gate electrode on the gate insulating film through patterning;
- forming a low concentration diffusion region by doping an impurity into the surface of the semiconductor substrate using the gate electrode as a mask through ion implantation;
- forming a nitride film over an entire surface;
- forming an interlayer film containing the impurity on the entire surface of the nitride film and leveling the interlayer film through heat treatment;
- selectively etching the interlayer film to form a contact hole onto the low concentration diffusion region and the gate electrode;
- forming a high concentration diffusion region by doping the impurity into the surface of the semiconductor substrate using the contact hole as the mask through the ion implantation;
- performing the heat treatment;
- depositing a metal material into a film on the entire surface by vacuum evaporation or sputtering and patterning the metal material by photolithography or etching;
- and
- covering the entire semiconductor substrate with a surface protective film.
Dependencies are inferred from the claim text.