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:
Jul. 18, 1995
Filed:
Jan. 28, 1993
Yutaka Kakehi, Hikari, JP;
Yoshinao Kawasaki, Kumage, JP;
Keizo Suzuki, Kodaira, JP;
Kazuo Nojiri, Higashimurayama, JP;
Hiromichi Enami, Tachikawa, JP;
Tetsunori Kaji, Tokuyama, JP;
Seiichi Watanabe, Kudamatsu, JP;
Yoshifumi Ogawa, Kudamatsu, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A plasma processing apparatus has a waveguide along which microwaves are propagated from a microwave generator to a plasma-forming region in a low-pressure processing chamber. The waveguide has a large cross-sectional area, to enable a large region of plasma to be achieved. Uniformity and stability of the plasma are improved by a mode restrictor which inhibits mixing of propagation modes which is otherwise liable to occur in a wide waveguide. The mode restrictor consists of electrically-conductive dividers which divide the waveguide cross-section into an array of sub-guides before the plasma-forming region.