Browse Prior Art Database

Process to Remove Residual Aqueous Photoresist

IP.com Disclosure Number: IPCOM000103433D
Original Publication Date: 1990-Nov-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 1 page(s) / 32K

Publishing Venue

IBM

Related People

Albrechta, SM: AUTHOR [+3]

Abstract

A process is disclosed that allows the removal of residual aqueous dry film photoresist that may occur in fabricating printed circuits.

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

Process to Remove Residual Aqueous Photoresist

      A process is disclosed that allows the removal of residual
aqueous dry film photoresist that may occur in fabricating printed
circuits.

      Typical dry film aqueous photoresists are stripped using
aqueous alkaline solutions (NaOH, KOH) at elevated temperatures.
Under certain circumstances, especially where fine-line geometries
are being defined, such solutions fail to completely remove the
photoresist.

      This residual photoresist is effectively removed by alternately
cycling the affected parts through aqueous solutions of alkaline
potassium permanganate, oxalic acid and the original stripping
solution (all at elevated temperature).  Water rinses are used
between each process chemical.

      The essentials of the process are shown in the figure. As
indicated, the process may be repeated.

      Disclosed anonymously.