Browse Prior Art Database

Laser Assisted, Selective Formation of Electroless Plating Seed Material

IP.com Disclosure Number: IPCOM000103457D
Original Publication Date: 1990-Nov-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 1 page(s) / 49K

Publishing Venue

IBM

Related People

Doany, FE: AUTHOR [+4]

Abstract

Disclosed is a method of plating of metals on non-metals using a laser to designate the plating sites.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 75% of the total text.

Laser Assisted, Selective Formation of Electroless Plating Seed Material

      Disclosed is a method of plating of metals on non-metals using
a laser to designate the plating sites.

      It is well known in the art that metal particles such as
palladium can be deposited on a surface by immersing the surface in a
"seed bath".

      It has been shown previously that Pd2+ can be ion-exchanged
onto the surface of a suitable polymer such as polyimide which was
previously hydrolyzed in basic solution. This Pd2+ layer can be
reduced in-situ to catalytically active, metallic Pd in the plating
bath or by heating for a short time in a reducing atmosphere, e.g.
forming gas.  The Pd2+ present on the polymer surface can be
reversibly removed by ion-exchange.  This affords the possibility of
patterning by reduction of the Pd2+ in selected regions of the
surface, followed by removal of the unreduced palladium.

      We disclose that a laser, such as an excimer laser, can be used
to locally heat small areas of the surface of the Pd2+ ion exchanged
polymer, e.g. polyimide, to convert the palladium to the metallic
form in a desired pattern.  The polymer material can act to reduce
the Pd2+, or the laser step can be carried out in the presence of a
reducing gas such as forming gas.  Subsequent treatment of the
surface with a simple salt solution, e.g. Na2SO4 or a dilute acid,
H2SO4, the unreduced Pd2+  is removed by ion-exchange leaving behind
the desired seed pattern....