The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 07, 2006
Filed:
Apr. 02, 2004
Steven R. Walther, Andover, MA (US);
Rajesh Dorai, Rockport, MA (US);
Harold Persing, Rockport, MA (US);
Jay Scheuer, Rowley, MA (US);
Bon-woong Koo, Andover, MA (US);
Bjorn O. Pedersen, Chelmsford, MA (US);
Chris Leavitt, Gloucester, MA (US);
Timothy Miller, South Hamilton, MA (US);
Steven R. Walther, Andover, MA (US);
Rajesh Dorai, Rockport, MA (US);
Harold Persing, Rockport, MA (US);
Jay Scheuer, Rowley, MA (US);
Bon-Woong Koo, Andover, MA (US);
Bjorn O. Pedersen, Chelmsford, MA (US);
Chris Leavitt, Gloucester, MA (US);
Timothy Miller, South Hamilton, MA (US);
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Abstract
A Faraday dose and uniformity monitor can include a magnetically suppressed annular Faraday cup surrounding a target wafer. A narrow aperture can reduce discharges within Faraday cup opening. The annular Faraday cup can have a continuous cross section to eliminate discharges due to breaks. A plurality of annular Faraday cups at different radii can independently measure current density to monitor changes in plasma uniformity. The magnetic suppression field can be configured to have a very rapid decrease in field strength with distance to minimize plasma and implant perturbations and can include both radial and azimuthal components, or primarily azimuthal components. The azimuthal field component can be generated by multiple vertically oriented magnets of alternating polarity, or by the use of a magnetic field coil. In addition, dose electronics can provide integration of pulsed current at high voltage, and can convert the integrated charge to a series of light pulses coupled optically to a dose controller.