Process for fabricating arbitrarily shaped through holes in a component

US4871418A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Jurgen Wittlinger · Böblingen, DE
• Johann Greschner · Neckartenzlingen, DE
• Thomas Bayer · Igersheim, DE
• Johann W. Bartha · Aidlingen, DE

Key dates

• Filing date: Mar 23, 1988
• Grant date: Oct 3, 1989
• Expiry date: Mar 23, 2008

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S438/928
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

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.