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. 27, 1990
Filed:
Dec. 23, 1988
Bernd Hensel, Frankfurt am Main, DE;
Dieter Hofmann, Bruchkobel, DE;
Leybold Aktiengesellschaft, Hanau, DE;
Abstract
An etching method whereby a sufficiently high etching rate is attained, in a uniform surface treatment that is very gentle on projecting edges of the substrates. Also the substrates are held at or brought to a sufficiently high temperature by the etching process. The method for etching substrates with a magnetic-field supported low-pressure discharge is characterized in that the magnetic field is decoupled from the substrates such that the magnetic field strength at the substrates is less than 6000 A/m. In the space between the substrates and the magnet system at least one electron emitter is disposed at a location at which a magnetic field strength is present that is greater than the field strength at the substrates but equal to or less than 12,000 A/m. On the side of the substrates facing away from the at least one electron emitter, at least one anode is disposed with an anode potential of +10 to +250 V with respect to ground. An etching potential between -100 V and -1000 V with respect to ground is applied to the substrates. The ratio of the gaps between the substrates and the surfaces of the substrates projected onto a projection plane carried through the gaps amounts to at least 0.1. The potential difference between the at least one emitter and the at least one anode is selected so high that an electron current (primary and secondary electrons) flows through the substrate gaps to the anode.