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:
Oct. 03, 1989
Filed:
Mar. 23, 1988
Jurgen Wittlinger, Boblingen, DE;
Johann Greschner, Pliezhausen, DE;
Thomas Bayer, Sindelfingen, DE;
Johann W Bartha, Sindelfingen, DE;
International Business Machines Corporation, Armonk, NY (US);
Abstract
According to a preferred embodiment, arbitrarily shaped holes are fabricated in 0.1 to 2 mm thick plates of polyoxymethylene homo- or copolymers. For that purpose, the polymeric substrate is photoresist-coated on either side; the desired pattern is simultaneously applied to both the front and the back side of the photoresist layers by imagewise exposure at optimum mask alignment; the photoresist layers are developed and blanket-exposed; the resultant photoresist structures are treated with a cyclic organosilicon compound and postbaked; the through holes are produced by sequential reactive ion etching of the polyoxymethylene from the front and the back side, each time down to a depth of about 2/3 of the substrate thickness; and the silylated photoresist masks are stripped from the front and the back side of the substrate.