Patent ID: 9288890
Filing Date: 2016-03-15
CPC Classification: H05H

Claim Text:
1. A method for treating a substrate, the method comprising: disposing a substrate in a chemical processing apparatus configured to treat the substrate with plasma products; flowing a first process gas at a first pressure into a first plasma region of a plasma generation chamber of the chemical processing apparatus; maintaining a first plasma in the first plasma region at a first plasma potential; flowing a second process gas at a second pressure into a second plasma region of the plasma generation chamber; maintaining a second plasma in the second plasma region at a second plasma potential by using a DC accelerator that maintains the second plasma potential sufficiently greater than the first plasma potential such that the second plasma potential causes an electron flux from the first plasma region towards the second plasma region, the second plasma being maintained using the electron flux from the first plasma region, the second plasma region being separated from the first plasma region via a separation member disposed there between, the separation member defining an array of openings sufficient to allow the electron flux from the first plasma region to the second plasma region; accelerating positive ions from the second plasma region towards a neutralizer grid disposed between the substrate and the second plasma region, the positive ions being accelerated by maintaining the second plasma such that the second plasma has a potential drop across a sheath boundary adjacent to the neutralizer grid, the neutralizer grid defining a plurality of channels oriented perpendicular to a surface of the substrate, a surface material of the plurality of channels being a material that temporarily holds electrons from the electron flux on surfaces of the plurality of channels such that positive ions traveling through the neutralizer grid receive electrons from the surfaces of the plurality of channels and continue traveling toward the substrate as a neutral particle; and exposing the substrate to a substantially anisotropic beam of neutral particles traveling from the neutralizer grid.