Etching method and semiconductor manufacturing method
An etching method which includes treating a workpiece having a stacked film ( 5 ) of a silicon oxide layer ( 2 ) and a silicon nitride layer ( 3 ) with an etching gas containing an unsaturated halon represented by the chemical formula: C 2 H x F (3−x) Br (in the chemical formula, x stands for 0, 1, or 2) so as to control the respective etch rates of the silicon nitride layer and the silicon oxide layer to the same level and form a high-aspect-ratio hole having a desirable profile at a high etch rate. Also disclosed is a method of manufacturing a semiconductor which includes by carrying out the etching method.
1. An etching method, comprising treating a workpiece having a stacked film of a silicon oxide layer and a silicon nitride layer with an etching gas containing an unsaturated halon represented by the following chemical formula: C 2 H x F (3−x) Br (in the chemical formula, x stands for 0, 1, or 2) to etch both the silicon oxide layer and the silicon nitride layer.
2. The etching method according to claim 1 , wherein the unsaturated halon is at least one selected from the group consisting of bromotrifluoroethylene, (E)-1-bromo-2-fluoroethylene, and 1-bromo-1-fluoroethylene.
3. The etching method according to claim 1 , wherein the etching gas further contains an inert gas.
4. The etching method according to claim 1 , wherein in the etching step, etching is performed with a plasma gas made from the etching gas.
5. A method of manufacturing a semiconductor, comprising performing etching by the etching method as claimed in claim 1 .
6. The etching method according to claim 2 , wherein the etching gas further contains an inert gas.
7. The etching method according to claim 2 , wherein in the etching step, etching is performed with a plasma gas made from the etching gas.
8. The etching method according to claim 3 , wherein in the etching step, etching is performed with a plasma gas made from the etching gas.
9. A method of manufacturing a semiconductor, comprising performing etching by the etching method as claimed in claim 2 .
10. A method of manufacturing a semiconductor, comprising performing etching by the etching method as claimed in claim 3 .
11. A method of manufacturing a semiconductor, comprising performing etching by the etching method as claimed in claim 4 .