PLASMA GENERATION AND PULSED PLASMA ETCHING

摘要

One or more plasma etching techniques are provided. Selective plasma etching is achieved by introducing a gas into a chamber containing a photoresist over a substrate, establishing a bias at a frequency to convert the gas to a plasma at the frequency, and using the plasma to etch the photoresist. The frequency controls an electron density of the plasma and by maintaining a low electron density causes free radicals of the plasma to chemically etch the photoresist, rather than physically etching using ion bombardment. A mechanism is thus provided for chemically etching a photoresist under what are typically physical etching conditions.

主权项

1. A method for plasma etching, comprising:
treating a photoresist that is over a substrate, the substrate situated between a first electrode and a second electrode in a chamber, the treating comprising:
introducing a first gas into the chamber such that the photoresist is exposed to the first gas;establishing a bias between the first electrode and the second electrode at a frequency using a power supply such that the first gas is converted to plasma at the frequency to etch the photoresist.