Browse Prior Art Database

Hydrogen Peroxide/Nitric Oxide Etch Solution

IP.com Disclosure Number: IPCOM000041710D
Original Publication Date: 1984-Mar-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 2 page(s) / 32K

Publishing Venue

IBM

Related People

Greene, KF: AUTHOR

Abstract

During an electroless nickel plating process, the plating rack also becomes nickel plated. It has been found that a hydrogen peroxide (H2O2) and nitric oxide (HNO3) solution provides superior etching of nickel without any deleterious side effects. Prior to this discovery, a 50% HNO2 solution (¼ hour immersion at room temperature) was employed, with less than satisfactory results (i.e., variability and slow etch rate). Higher HNO3 solutions and higher operating temperatures increased harmful fuming. It was found that the addition of small quantities of H2O2 (which by itself is not a nickel etchant) to an HNO3 solution has a marked effect on the etch rate of nickel.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Hydrogen Peroxide/Nitric Oxide Etch Solution

During an electroless nickel plating process, the plating rack also becomes nickel plated. It has been found that a hydrogen peroxide (H2O2) and nitric oxide (HNO3) solution provides superior etching of nickel without any deleterious side effects. Prior to this discovery, a 50% HNO2 solution (1/4 hour immersion at room temperature) was employed, with less than satisfactory results (i.e., variability and slow etch rate). Higher HNO3 solutions and higher operating temperatures increased harmful fuming. It was found that the addition of small quantities of H2O2 (which by itself is not a nickel etchant) to an HNO3 solution has a marked effect on the etch rate of nickel. The figure illustrates this effect by plotting the ratio of H2O2 (Volume %, 30% H2O2 solution) and HNO3 (Volume %, 70% HNO3 solution) versus nickel etch rate in 70 H2O solutions. From the figure it may be seen that the H2O2-HNO3 combination greatly increases the nickel etch rate, particularly in the range where H2O2 represents from zero percent to five times the volume of HNO3 in the total solution (the latter being the 25% H2O2/5% HNO3 point in the figure).

1

Page 2 of 2

2

[This page contains 3 pictures or other non-text objects]