Patent ID: 6464891
Filing Date: 2002-10-15
Classification: C23C,H01J,H01L

Abstract:
A method for repetitive ion beam processing of a surface on a substrate with a carbon containing ion beam using a gridded RF or microwave ion source, the RF or microwave ion source including a vessel having a plurality of walls defining an interior for containing a plasma, the vessel including an inlet communicating with the interior of the vessel and connectable to a source of a precursor gas, an RF or microwave energy generator for communication with the gas in the interior of the vessel and for effecting ionization of the gas in the vessel and creating the plasma, and an ion optics assembly through which an ion beam is dischargable, the optics assembly having a first conductive grid member, the method comprising the steps of:providing a carbon containing plasma in the RF or microwave ion source; generating a carbon containing ion beam from said carbon containing plasma; processing said surface of the substrate with said ion beam under predetermined conditions including a discharge power level, a flow of precursor gas and an application of a potential to the plasma; and generating in the RF or microwave ion source a plasma formed from a mixture of an inert gas and oxygen having a ratio of mass flow rates of inert gas to oxygen in the range from about 1-to-4 to about 2-to-1 to reactively etch precipitates formed on the grid and source walls with ions and radicals formed in said inert gas and oxygen plasma mixture.