Plasma etching method and plasma etching apparatus

摘要

A plasma etching method deposits a silicon-containing deposit by a plasma processing using a Si-containing gas on an object to be processed that includes a film to be processed, an organic film formed in a plurality of narrow linear portions on the film to be processed, and a rigid film that covers both the film to be processed which is exposed between the linear portions and the linear portions. In the plasma etching method, each of the plurality of narrow linear portions of the organic film and the film to be processed between the linear portions are exposed by etching the silicon-containing deposit by plasma of CF-based gas and CHF-based gas after the silicon-containing deposit is deposited.

主权项

1. A plasma processing method comprising:
preparing an object to be processed in a processing chamber, the object to be processed including a film to be processed, an organic film formed in a plurality of first narrow linear portions on the film to be processed, and a rigid film that covers both the plurality of first narrow linear portions and the film to be processed which is exposed between the plurality of first narrow linear portions; depositing a silicon-containing deposit on a surface of the rigid film within the processing chamber by a plasma process with plasma being generated by introducing Si-containing gas on the surface of the rigid film; first etching the silicon-containing deposit and the rigid film by a plasma process with plasma being generated by introducing a processing gas including CF-based gas and CHF-based gas into the processing chamber, thereby exposing a top of each of the plurality of first narrow linear portions of the organic film and the film to be processed in first openings between the plurality of first narrow linear portions; ashing and selectively removing the organic film so as to form a plurality of second linear portions and spaces between the second linear portions; second etching the rigid film in each of the plurality of second linear portions; and third etching the film to be processed using the rigid film of each of the second linear portions as a mask so as to form third openings, wherein, the plurality of second linear portions are formed in a regular width in the second etching process, and the cross-section of each of the third openings is formed in a rectangular shape perpendicular to the film to be processed in the third etching process.