CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority from Japanese Patent Application No. 2019-237331 filed on Dec. 26, 2019 with the Japan Patent Office, the disclosure of which is incorporated herein in its entirety by reference.

TECHNICAL FIELD

The present disclosure relates to an etching method and an etching apparatus.

BACKGROUND

There is a technology for forming a deep hole in a silicon oxide film formed on a workpiece, or in a multilayer film in which a silicon oxide film and a silicon nitride film are alternately laminated on a workpiece. See, for example, Japanese Patent Laid-Open Publication No. 2016-039310.

SUMMARY

An etching method according to an aspect of the present disclosure includes a step of providing, a step of setting, and a step of etching. In the step of providing, a substrate including an etching film including a silicon oxide film, and a mask formed on the etching film is provided on a stage. In the step of setting, a temperature of the stage is set to be 0° C. or less. In the step of etching, the silicon oxide film is etched through the mask by generating plasma from a gas containing fluorine, nitrogen, and carbon, and having a ratio of the number of fluorine to the number of nitrogen (F/N) in a range of 0.5 to 10.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

