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:
Mar. 30, 2004
Filed:
Nov. 02, 2001
Akira Nakano, Miyagi-ken, JP;
Tadahiro Ohmi, Miyagi-ken, JP;
Alps Electric Co., Ltd., Tokyo, JP;
Abstract
A plasma processing apparatus includes a plurality of plasma processing units. Each of the plasma processing units has a plasma excitation electrode, a radiofrequency generator connected to the plasma excitation electrode, and a matching circuit which matches the impedance between the radiofrequency generator and the plasma processing unit. The absolute value |&Dgr;RA| of the difference &Dgr;RA between the AC resistance RA at a time t and the AC resistance RA at a later time t and the absolute value |&Dgr;RB| of the difference &Dgr;RB between the AC resistance RB at the time t and the AC resistance RB at the later time t are maintained at a value less than an upper limit. Based on these values, whether or not the plasma processing apparatus which is reassembled or used at a user site maintains a required level of performance is evaluated.