Browse Prior Art Database

Improved Metal/Polymer Adhesion Durability by Ion Beam Modification

IP.com Disclosure Number: IPCOM000109148D
Original Publication Date: 1992-Jul-01
Included in the Prior Art Database: 2005-Mar-23
Document File: 1 page(s) / 59K

Publishing Venue

IBM

Related People

Anschel, M: AUTHOR [+4]

Abstract

Although surface precleaning by ions in a radiofrequency plasma or from an ion gun has been used in practice to achieve initially good adhesion of deposited metals on polyimides, the adhesion strength tends to degrade to low levels when these structures are subjected to elevated temperature process cycles (up to 400~C for several hours), or temperature/humidity (T&H) cycles simulating service environments. In this article, a method is described that will not only enable a high metal/polyimide adhesion but also its durability under the above described exposure stresses. The method involves bombardment of the surface of the polyimide with low energy (0.5 to 2 keV) inert gas (Ar, Xe, etc.) ions to modify (carbon enrich and densify) the polymer surface prior to the deposition of the adhesion layer metal, typically chromium.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 68% of the total text.

Improved Metal/Polymer Adhesion Durability by Ion Beam Modification

      Although surface precleaning by ions in a radiofrequency plasma
or from an ion gun has been used in practice to achieve initially
good adhesion of deposited metals on polyimides, the adhesion
strength tends to degrade to low levels when these structures are
subjected to elevated temperature process cycles (up to 400~C for
several hours), or temperature/humidity (T&H) cycles simulating
service environments.  In this article, a method is described that
will not only enable a high metal/polyimide adhesion but also its
durability under the above described exposure stresses.  The method
involves bombardment of the surface of the polyimide with low energy
(0.5 to 2 keV) inert gas (Ar, Xe, etc.) ions to modify (carbon enrich
and densify) the polymer surface prior to the deposition of the
adhesion layer metal, typically chromium.  Significant benefits can
be gained if this modified layer contains metallic  elements such as
Cu or Au to the extent of 5 to 15 atomic % implanted close to
the metal/polyimide interface.  Although the specific role of these
species is not fully understood, the net result is that such a
modified region acts as a barrier to water transport.  This, in turn,
leads to the retardation of the kinetics of the oxidation of the
metal adhesion layer by the water absorbed in the polyimide during
thermal and T&H cycles which is one of the primary mechanisms of
adhesion degradation.  A...