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:
May. 29, 2001
Filed:
Mar. 08, 2000
Applicant:
Inventors:
Leslie Michael Lea, Oxfordshire, GB;
Edward Guibarra, Cardiff, GB;
Assignee:
Surface Technology Systems Limited, Gwent, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B23K 1/000 ;
U.S. Cl.
CPC ...
B23K 1/000 ;
Abstract
Plasma processing apparatus frequently incorporates an antenna fed from a power supply and in this invention a power supply feeds a conventional matching circuit (,), which in turn is connected to the primary (,) of a transformer (,). The antenna (,) is coupled across the secondary winding (,) of the transformer (,) and that winding is tapped to ground at (,). This creates a virtual earth (,) near the mid point of the antenna (,) significantly reducing the variation, along the length of the antenna, in the power supplied to the plasma.