Fast atomic layer etch process using an electron beam

摘要

An etch process gas is provided to a main process chamber having an electron beam plasma source, and during periodic passivation operations a remote plasma source provides passivation species to the main process chamber while ion energy is limited below an etch ion energy threshold. During periodic etch operations, flow from the remote plasma source is halted and ion energy is set above the etch threshold.

主权项

1. A method of removing an overlying film comprising:
generating a plasma in a chamber by providing an electron beam in said chamber; coupling an RF bias voltage to a workpiece in said chamber, said workpiece comprising said overlying film; performing a passivation process for a time duration corresponding to a desired thickness of a layer of said overlying film, said passivation process comprising:
enabling flow of plasma by-products from a remote plasma source containing a passivating gas;setting energy of ions in said chamber to a first ion energy level less than a first minimum ion energy required for etching said overlying film; after said time duration, halting said passivation process and performing an etching process by:
setting energy of ions in said chamber to a second ion energy level exceeding said first minimum ion energy.