Successes within the PCB market
Periodic Pulse and Periodic Pulse Reverse electrochemical processes are not a new phenomena. These techniques have been in use for approximately 50 years. Pulse techniques were used in the mid 1980's, when gold prices were high and pulse deposition promised less material consumption. Later these promising technologies were revitalized in the early 90's, when an application that was never considered in the previous wave of enthusiasm was investigated. Copper deposition on high-end printed circuit boards (PCB's) was at the very limit of what DC processes could achieve, and it turned out PPR technology could go beyond that. All major process suppliers built business units around the PPR copper technology, thus shielding it from the rest of the electrochemical world and the General Metal Finishing marketplace.

Opportunities within the General Metal Finishing (GMF) market

Until around 2000, when the success of pulse reverse processes in the printed circuit board industry finally convinced many in research that electrochemistry as a whole could benefit from similar processing schemes. An understanding of the comparably diverse GMF marketplace was necessary. A direct technology transfer from the successes of PCB to GMF was extremely limited. This was mainly due to the various types of industries and applications that exist in the GMF industry. With this in mind, knowledge of the processes and various types of metal finishing applications (electroplating, electroforming, anodizing, electrochemical machining, etc.) was required. The process, which includes chemistry, bath configuration and power, needed to be developed prior to implementation into the existing metal finishing marketplace. With this process understanding and development, metal finishers could realize the benefits of implementing
PPR technology into their existing applications almost immediately.

Successes within the GMF Market

As processes are developed, thus allowing for additional materials to become available with PPR, metal finishers can experience the benefits of a broad scope of opportunities. Today opportunities include applications with Copper, Nickel and Nickel electroforming, Silver, Gold, Zinc, etc.

Developing applications include micro electro mechanical systems, or MEMS for short. And not only electro deposition, but also electro chemical machining and anodizing processes are being developed.

Currently it is generally agreed upon that PPR technology is not just a component-wise plug-and-play replacement for DC technology. DC technology was developed during the better part of the last century. This process, over time has been improved and optimized to where it is today. PPR shouldn't be considered a competing technology to DC. It should be looked as an extension and a refinement to a process that is very strong and present in today's Metal Finishing industry.

Advantages of Periodic Pulse Reverse (PPR) Plating

-Improved throwing power

-Improved surface covering / deposit distribution

-Brightening

-Improved ductility / hardness

-Change of morphology, roughness (voids, porosity)

-Control over grain size

-Improved adherence to substrate

Solutions to a successful PPR application include the optimization of the following:
- electrolyte composition
- additive package
- bath agitation
- cell (bath) design
- rectifier design
- pulse pattern

Pulse reverse plating leads to significantly improved surface distribution and throwing power