Electronics Assembly Knowledge, Vision & Wisdom
Direct Determination of Phosphorus Content in Electroless Nickel Plating
Direct Determination of Phosphorus Content in Electroless Nickel Plating
Developments in XRF instrument hardware and software have extended the measurement application of electroless plating processes to nearly any substrate.
Analysis Lab

Analysis Lab programs cover topics including:
Corrosion, Contamination, Data Acquisition, ESD and EOS, Inspection, Measurement, Profiling, Reliability, R&D, RFID, Solder Defects, Test, Tombstoning, X-ray and more.
Submit A Comment
Comments are reviewed prior to posting. You must include your full name to have your comments posted. We will not post your email address.

Your Name


Your Company


Your E-mail


Your Country


Your Comment



Authored By:
Michael Haller
Jim Bogert, Ryan Boyle
Fischer Technology, Windsor CT, USA

Volker Rößiger, Wolfgang Klöck
Helmut Fischer GmbH, Sindelfingen, Germany

Summary
Electroless plating processes are popular because of their performance, reliability and cost effectiveness. The process combines unique deposit properties such as uniform plating build up regardless of geometry, excellent corrosion resistance, superior hardness and wear and the ability to plate on non-conducting materials. The most commonly used electroless plating process is Electroless Nickel (EN) plating using nickel phosphorus baths.

The phosphorus content plays a fundamental role in all physical properties of the deposit. It is, therefore, critical to control the phosphorus content within a relatively tight range. X-ray fluorescence is an excellent method to not only measure plating thickness but also weight percent elemental composition of coatings. Previously, it was only possible to measure plated phosphorus content on steel substrates. New developments in XRF instrument hardware and software have extended the measurement application of electroless plating processes to nearly any substrate. The simultaneous measurement of thickness and composition is critical.

Conclusions
New developments in XRF hardware and software technology have made it possible to simultaneously measure % phosphorous and NiP coating thickness in air. Being able to measure the phosphorous content directly now allows determination of the % phosphorous in electroless Ni-plantings on substrates in addition to iron, such as, Al or even non metallic substrates. Instruments with SDDs can measure the P-K radiation quite well using soft primary excitation (10 kV, non-filtered). Coating thickness is determined using harder excitation (30 keV or 50 kV).

The information depth for phosphorus is relatively low (<1 m) due to the low energy of P-K fluorescence. Conventional indirect determination of phosphorus can still be regarded as a relatively robust method with proportional counter tube instruments - the only option with these instruments.

Initially Published in the IPC Proceedings

Comments
No comments have been submitted to date.
Free Newsletter Subscription
Every issue of the Circuit Insight email newsletter will bring you the latest information on the issues affecting you and your company.

Insert Your Email Address

Directory Search


Program Search
Related Programs
bullet Use of High Purity Water to Eliminate Contamination And Achieve Cleanliness
bullet Micro Trace Resistive Technology
bullet How Do You Remove Oxidation from PCBs?
bullet Reliability of ENEPIG by Sequential Thermal Cycling and Aging
bullet What is Causing Dimples in Blind Via Pads?
bullet Nanomaterials Performance Advantages
bullet Big Problems with HASL Finish
bullet Room Temperature Fast Flow Reworkable Underfill for LGA
bullet New Phosphorus-based Curing Agents for PWB
bullet Printed Circuit Structures, the Evolution of Printed Circuit Boards
More Related Programs