Method for dry etching Al2O3 film
AssigneeHitachi High-Technologies Corporation
InventorsKentaro Yamada, Takeshi Shimada, Kotaro Fujimoto
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Abstract
The invention provides a dry etching method for processing a wafer having an Ru film formed on a thick Al2O3 film to be used for a magnetic head, capable of realizing high selectivity. In the etching of a wafer having disposed on an NiCr film 15 an Al2O3 film 14, an Ru film 13, an SiO2 film 12 and a resist mask 11, the Ru film 13 is etched via plasma using a processing gas containing Cl2 and O2 (FIG. 1(c)), and thereafter, the Ru film 13 is used as a mask to etch the Al2O3 film 14 via plasma using a gas mixture mainly containing BCl3 and also containing Cl2 and Ar (FIG. 1(d)).
Claims2
A method for dry etching an Al2O3 film which has a thickness of 200 nm to 1,000 nm, and is arranged on a nickel chrome alloy film of a sample having a ruthenium film arranged on the Al2O3 film, comprising the steps of:
- dry etching the ruthenium film using a gas mixture containing Cl2 O2 and Ar, so as to form an etched ruthenium film;
- and
- dry etching the Al2O3 film, using a gas mixture containing BCl3, Cl2 and Ar, so as to form at etched Al2O3 film,
- wherein the ruthenium film is dry etched using a patterned silicon oxide film and a patterned resist film as a mask, so as to form the etched ruthenium film;
- and
- wherein the Al2O3 film is dry etched using a patterned ruthenium film and the patterned silicon oxide film as a mask, so as to form the etched Al2O3 film.
Dependencies are inferred from the claim text.