Method for detecting scratch of an insulating film
AssigneeOki Electric Industry Co., Ltd.
InventorHiroyuki Kawano
Life of this patent
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Abstract
In a device having a structure in which a silicon oxide film, a silicon nitride film, and a silicon oxide film are layered on a silicon substrate in that order from a bottom position, CMP polishing is performed in order for a top layer of a silicon oxide film to residually exist. An etchant for selectively etching a silicon nitride film only is then used. Only a nitride film in a scratched portion, the depth of which is deeper than the depth of the silicon oxide film, is selectively etched, and only the scratch, the depth of which is deeper than the depth of the residual film of the silicon oxide film, is exposed.
Claims11
A method for detecting a scratch of an insulating film in a semiconductor device, comprising:
- preparing a silicon substrate on which a first insulating film, a silicon nitride film, and a second insulating film are layered in that order, wherein the silicon nitride film is thinner than the first insulating film in thickness;
- polishing the second insulating film by a chemical mechanical polishing process;
- and
- removing the silicon nitride film exposed by the scratch after the chemical mechanical polishing process.
A method for detecting a scratch of an insulating film in a semiconductor device, comprising:
- preparing a silicon substrate on which a first insulating film, a plurality of intermediate films, and a second insulating film are layered in that order, wherein the plurality of intermediate films includes two or more silicon nitride films with an insulating film formed between each pair of silicon nitride films, and the plurality of intermediate films is thinner the first insulating film in thickness;
- polishing the second insulating film by a chemical mechanical polishing process;
- and
- removing the silicon nitride films exposed by the scratch after the chemical mechanical polishing process.
Dependencies are inferred from the claim text.