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. 02, 1989
Filed:
Sep. 08, 1987
Mervyn H Davis, Chichester, GB;
Nordiko Limited, Hampshire, GB;
Abstract
An electrode assembly is described for use in plasma processes, such as reactive dry etching and plasma deposition. This includes a primary electrode which is electrically insulated from the vacuum chamber in which it is mounted in use. The primary electrode may be connected to an r.f. or d.c. power source and has a cylindrical hole with an insulated subsidiary electrode at the bottom of the hole which can be earthed or allowed to adopt a floating voltage in use. Magnets are used to trap electrons adjacent the walls of the hole. These may consist of a plurality of elongate magnets positioned around an annular pole plate with their largest dimension arranged longitudinally with respect to the pole plate and the hole, with their magnetic axes arranged radially, and with alternating polarity around the inner periphery of the pole plate. In use an r.f. frequency (e.g. 13.56 MHz) may be applied to the primary electrode while a reactant gas (e.g. C.sub.2 F.sub.6 or a C.sub.2 F.sub.6 /CHF.sub.3 mixture) is admitted to the vacuum chamber. The silicon wafer or other substrate to be etched is placed on a substrate table within the chamber which can also be connected to an r.f. power source.