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US 6,646,277 B2Granted
Charging control and dosimetry system for gas cluster ion beam
AssigneeEpion Corporation
InventorsMichael E. Mack, Bruce K. Libby
Life of this patent
Estimating the term…
Abstract
A method and apparatus for gas cluster ion beam (GCIB) processing uses X-Y scanning of the workpiece relative to the GCIB. A neutralizer reduces surface charging of the workpiece by the GCIB. A single Faraday cup sensor is used to measure the GCIB current for dosimetry and scanning control and also to measure and control the degree of surface charging that may be induced in the workpiece during processing.
Claims13
An apparatus utilizing a gas cluster ion beam for processing a surface of a workpiece, the apparatus comprising:
- a vacuum vessel;
- a gas cluster ion beam source within the vacuum vessel for producing a gas cluster ion beam having a beam current;
- an accelerator for accelerating the gas cluster ion beam along a trajectory;
- workpiece holding means for holding the workpiece for gas cluster ion beam processing;
- controllable moving means for selectively scanning said workpiece holding means and the workpiece through said gas cluster ion beam at a location along said trajectory, between said accelerator and said current measurement means, and for selectively removing the workpiece holding means and the workpiece from said gas cluster ion beam trajectory;
- control means for providing signals to said controllable moving means for scanning the workpiece and for removing the workpiece and workpiece holder from said gas cluster ion beam trajectory to allow measurement of said beam current;
- and
- current measurement means disposed along said trajectory for measuring current, said current measuring means having at least two controllable modes, one of said modes selectively measuring a sample of the gas cluster ion beam current and another of said modes selectively measuring a sample of the total current available for charging the workpiece, said control means providing control signals for selecting between the two modes.
5 more elements
A method of processing the surface of a workpiece using a gas cluster ion beam comprising the steps of:
- forming a gas cluster ion beam within a vacuum vessel, said gas cluster ion beam having a gas cluster ion beam current;
- accelerating said gas cluster ion beam along a trajectory;
- controllably holding the workpiece for gas cluster ion beam processing out of the trajectory of said gas cluster ion beam;
- providing a current measurement means having at least two controllable modes, one of said modes for selectively measuring a sample of the gas cluster ion beam current and another of said modes selectively measuring a sample of the total current available for charging the workpiece;
- selecting said mode for measuring a sample of the gas cluster ion beam current;
- measuring, at least once, a sample of the gas cluster ion beam current;
- moving, at least once, the workpiece into the trajectory of said gas cluster ion beam for processing;
- and
- using said at least one measurement of a sample of the gas cluster ion beam current to control a dosage of said gas cluster ion beam applied to the workpiece during said processing.
6 more elements
A method of processing the surface of a workpiece using a gas cluster ion beam comprising the steps of:
- forming a gas cluster ion beam within a vacuum vessel, said gas cluster ion beam having a gas cluster ion beam current;
- accelerating said gas cluster ion beam along a trajectory;
- controllably holding the workpiece for gas cluster ion beam processing out of the trajectory of said gas cluster ion beam;
- providing a current measurement means having at least two controllable modes, one of said modes for selectively measuring a sample of the gas cluster ion beam current and another of said modes selectively measuring a sample of the total current available for charging the workpiece;
- selecting said mode for measuring a sample of the total current;
- measuring a sample of total current available for workpiece charging;
- using said sample of said total current available as a basis for reducing said total current available for workpiece charging to a predetermined safe level;
- and
- moving the workpiece into the trajectory of said gas cluster ion beam for processing.
6 more elements
A method of processing the surface of a workpiece using a gas cluster ion beam comprising the steps of:
- forming a gas cluster ion beam within a vacuum vessel, said gas cluster ion beam having a gas cluster ion beam current;
- accelerating said gas cluster ion beam along a trajectory;
- controllably holding the workpiece for gas cluster ion beam processing out of the trajectory of said gas cluster ion beam;
- providing a current measurement means having at least two controllable modes, one of said modes for selectively measuring a sample of the gas cluster ion beam current and another of said modes selectively measuring a sample of the total current available for charging the workpiece;
- selecting said mode for measuring a sample of the total current;
- measuring a sample of total current available for workpiece charging;
- using said sample of said total current available as a basis for reducing said total current available for workpiece charging to a predetermined safe level;
- selecting said mode for measuring a sample of the gas cluster ion beam current;
- measuring, at least once, a sample of the gas cluster ion beam current;
- moving, at least once, the workpiece into the trajectory of said gas cluster ion beam for processing;
- and
- using said at least one measurement of a sample of the gas cluster ion beam current to control a dosage of said gas cluster ion beam applied to the workpiece during processing.
9 more elements
Dependencies are inferred from the claim text.