Browse Prior Art Database

Metallizing a Conductor using a Novel Sensitizer Formulation

IP.com Disclosure Number: IPCOM000088356D
Original Publication Date: 1977-Jun-01
Included in the Prior Art Database: 2005-Mar-04
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Depew, JR: AUTHOR [+4]

Abstract

This article describes an improved sensitizing step in the process of metallizing a nonconductive substrate. One conventional metallizing process is a six-step process as follows:. 1. Oxidizing the surface. 2. Removing over treated material from the surface. 3. Neutralizing the surface. 4. Sensitizing the surface. 5. Activating the surface. 6. Electroless plating.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 70% of the total text.

Page 1 of 1

Metallizing a Conductor using a Novel Sensitizer Formulation

This article describes an improved sensitizing step in the process of metallizing a nonconductive substrate. One conventional metallizing process is a six-step process as follows:. 1. Oxidizing the surface. 2. Removing over treated material from the surface. 3. Neutralizing the surface. 4. Sensitizing the surface.
5. Activating the surface. 6. Electroless plating.

In the first step, the surface is oxidized, e.g., by a chrome-sulphuric oxidation, as disclosed in U.S. Patent 3,142,582. The second step is a conditioning step wherein the over-treated material is removed, e.g., by sodium hydroxide, as disclosed in that patent. The next step is a neutralizing step to remove any residual chromate ions and is preferably a dip in hydrochloric acid.

The sensitizing step follows, and an improved sensitizer is used. The sensitizer utilizes both Sn/+2/ and Sn/+4/ ions. The molar ratio of the Sn/+2/ over Sn/+4/ is 0.5 to 1.0 over 1. A preferred sensitizer solution is 0.06M SnCl(4) 5H(2)O; .03 - .06M SnCl(2) Times 2H(2)0; 0.14M NaOH. The SnCl provides the Sn/+4/ ions and the SnCl(2) provides the Sn/+2/ ions. The NaOH is used to adjust the pH to about 0.9 + or = .05. A specific preferred solution is 21 gm/1 of SnCl(4) Times 5H 0; 14 gm/l of SnCl(2) Times 2H(2)0 and 4 gm/1 of NaOH. The ratio of Sn/+2/ to Sn/+4/ ions is derived by varying the SnCl(2) Times 2H(2)0 within the given limits above. The solution is aged for ab...