Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Cleaning and Activation Solution for Parts which are Plated in Electroless Goldbaths

IP.com Disclosure Number: IPCOM000112956D
Original Publication Date: 1994-Jun-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 31K

Publishing Venue

IBM

Related People

Schuster, U: AUTHOR

Abstract

Electroless goldbaths comprising a reduction agent for the gold deposition are used for plating bondable gold-layers on printed circuits and MCMs (organic/ceramic).

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 98% of the total text.

Cleaning and Activation Solution for Parts which are Plated in Electroless
Goldbaths

      Electroless goldbaths comprising a reduction agent for the gold
deposition are used for plating bondable gold-layers on printed
circuits and MCMs (organic/ceramic).

      Due to the fact that these goldbaths are relatively unstable
regarding overplating and throwing power, it is necessary that no
surface contamination of organic or metallic origin can occur.

The following pretreatment can be used to clean and activate surfaces
before the gold plating.

Chemical Composition:
 NaCN/KCN       2-5 g/l
 H[2]O[2]       1-5 g/l
 Air bubbling
 Wetting Agent  0.05-0.1 g/l (perfluorite type agent)
 Temperature    20-40ºC
 Time           0.5-4 min.

      Instead of using peroxide, bubbling air could be used as an
oxidation agent.  When peroxide is used, the life time of the
solution is limited to 2-3 hours.  After that time the cyanide will
be oxidized.

      The life time of the bath can be increased by using air only
when there are parts in the activtion tank.

      Cyanide forms soluble complex-compounds with Nickel, Copper and
Gold (mostly base materials) and is removing this metallic
contamination from insulated areas, so that problems with overplating
could be reduced.  Also the base material is partially attacked by
the cyanide.  Thus, the surface of the part becomes more active and
the throwing power of the electroless goldbath...