Etching for manufacture of semiconductor devices
AssigneeKabushiki Kaisha Toshiba
InventorsMami Saito, Hiroshi Tomita, Kunihiro Miyazaki, Soichi Nadahara
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Abstract
A method of manufacture of semiconductor devices is disclosed, which includes an etching process carried out by using an undiluted etching solution containing H2SO4 and NH4F or H2SO4 and HF as main components, and having an H2O content set to 5 wt % or lower. Moreover, a method of manufacture of semiconductor devices is disclosed, which includes selective etching an SiN film by using a mixed solution of H2SO4 and H2O, or an etching solution obtained by adding a small amount of hydrofluoric acid to the mixed solution.
Claims23
A method of manufacture of semiconductor devices, comprising:
- etching carried out by using a solution containing H2SO4 and NH4F, or H2SO4 and HF, as main components, and having an H2O content in the solution set to 5 wt % or lower as an undiluted etching solution.
A method of manufacture of semiconductor devices, comprising:
- selective etching carried out for one of an SiN film and an SiON film formed by a CVD method with respect to one selected from an SiO2 film, an Si substrate, and an Si film at an etching solution temperature of 150° C. or higher, by using a mixed solution of H2SO4 and H2O having an H2O content set at 10 wt % to 40 wt % with respect to the H2SO4 as an etching solution.
A method of manufacture of semiconductor devices, comprising:
- selective etching carried out for one of an SiN film and an SiON film formed by a CVD method with respect to one selected from an SiO2 film, an Si substrate, and an Si film at an azeotropic point temperature, by using a solution obtained by adding HF of 0.1 wt % or lower to a mixed solution of H2SO4 and H2O having an azeotropic point set at 100° C. or higher as an etching solution.
A method of manufacture of semiconductor devices, comprising:
- selective etching carried out for one of an SiN film and an SiON film formed by a CVD method with respect to one selected from an SiO2 film, an Si substrate, and an Si film at an etching solution temperature of 100° C. or higher, by using a solution obtained by adding HF of 0.1 wt % or lower to a mixed solution of H2SO4 and H2O having an H2O content set at 10 wt % to 50 wt % with respect to the H2SO4 as an etching solution.
A method of manufacture of semiconductor devices, comprising:
- selective etching a specific one or a plurality of insulating films among a plurality of films different from one another in a property and exposed to a surface of a semiconductor substrate, with respect to another film, by using an undiluted etching solution or a solution obtained by diluting the undiluted etching solution with a sulfuric acid solution having an H2O content set at 5 wt % or lower, as a first etching solution, the undiluted etching solution containing H2SO4 and NH4F or containing H2SO4 and HF, as main components, and has an H2O content set to 5 wt % or lower;
- selective etching a specific one or a plurality of insulating films among a plurality of films different from one another in a property and exposed to the surface of the semiconductor substrate, by using the undiluted etching solution or a solution obtained by diluting the undiluted etching solution with the sulfuric acid solution having the H2O content set at 5 wt % or lower, as a second etching solution;
- and
- unselective etching a plurality of insulating films exposed to the surface of the semiconductor substrate, by using the undiluted etching solution, or a solution obtained by diluting the undiluted etching solution with the sulfuric acid solution having the H2O content set at 5 wt % or lower, as a third etching solution.
A method of manufacture of semiconductor devices, comprising:
- etching an insulating film exposed to a surface of a semiconductor substrate, by using an undiluted etching solution containing H2SO4 and NH4F, or H2SO4 and HF as main components, and having an H2O content set to 5 wt % or lower, or by using a solution obtained by diluting the undiluted etching solution with a sulfuric acid solution having an H2O content set at 5 wt % or lower, as an etching solution;
- subjecting the surface of the semiconductor substrate after the etching to preliminary cleaning by a sulfuric acid solution having an H2O content set at 5 wt % or lower;
- and
- subjecting the surface of the semiconductor substrate after the preliminary cleaning to real cleaning by pure water.
Dependencies are inferred from the claim text.