Browse Prior Art Database

Regenerative Aprotic Polyimide Etching

IP.com Disclosure Number: IPCOM000102967D
Original Publication Date: 1990-Apr-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 1 page(s) / 45K

Publishing Venue

IBM

Related People

Glenning, JJ: AUTHOR [+4]

Abstract

This disclosure describes the tooling (see fig.) which could be used with the electrochemical etching of polyimide (1).

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Regenerative Aprotic Polyimide Etching

      This disclosure describes the tooling (see fig.) which could be
used with the electrochemical etching of polyimide (1).

      Organic anionic reducing agents, as generated in one known
manner, are placed in contact with the surface of the polyimide to be
etched.  In the reaction, the polyimide is reduced to a radical-anion
or dianion form, which are soluble in aprotic solvents.  Concomitant
with the polyimide reduction is oxidation of the organic reducing
agent.  The chemical solution, which contains the soluble polyimide
in an anionic form, is pumped from the etching chamber into a holding
tank.  If oxygen is bubbled through this mixture while in the holding
tank, the soluble polyimide anion is reoxidized back to its neutral
form due to the electron scavenging nature of oxygen.  The resultant
precipitate can be removed from the mixture by either filtration or
centrifugation.  Nitrogen is purged through the system to then remove
the oxygen from solution which is then returned to the etching
chamber so the reduction of polyimide can proceed.  Using this
regenerative technique, no reagents of the electrolysis reactions or
polyimide are consumed by the etching operation.  The only chemical
loss results from dragout on etched product and/or through chemical
exhaust.

      Disclosed anonymously.