(1)What is photo electroforming

"Photo electroforming" is an electroforming method developed by applying the photomechanical technology. This method has enabled ultra-fine processing at ultrahigh precision. Compared to the other processing methods, photo electroforming can reproduce a number of same images on a broader area at high precision. Owing to this superior feature, photo electroforming has been developed as a processing method for precision electronic components.

The photoresist technology has been applied to the production of CD and DVD discs. They are produced by applying photoresist on the glass master disc, followed by perforation using physical energy to record data and nickel electroforming. This processing method is frequently used for manufacturing plates with precise perforation.

The other method of using photoresists besides photo electroforming is called photo etching, which uses chemical reactions to dissolve and corrode the surface. This method is applied for precise processing of thin plates and films. Yet, photo electroforming is a better choice for fine processing of complex-shaped objects at higher precision.

Photo electroforming is similar to photo etching and chemical milling processes. The difference is that electroforming electronically deposits a metal layer on an area not covered by protective films (photoresist) whereas the latter uses etching (corrosive liquid) to dissolve the surface chemically.

Photo-electroforming can be used for more complex processing by integrating another precision processing method called photo etching.

Photo electroforming produces higher precision than the etching method, but it uses the plating technology to electroform thin metal plates into a desired shape. For this reason, this method can be used for certain types of metals, such as nickel, copper, gold, silver, nickel-copper lamination layer, nickel alloy and so on. The difference from the conventional electroforming is the process of creating an original plate and forming a photoresist layer.

Stamping (metal pressing) requires high precision molds. The mold production is not only time-consuming but also expensive, less accurate, and prone to processing strains or burrs. Compared to this, the photo electroforming method is less expensive, resistant to processing strains, and highly accurate. Although it requires an original plate that takes days to complete, you can create precise and sharp objects that you were not able to produce using stamping or electro-discharge machining.

The electroforming method is applied for production of electronic components and precision machinery parts for its excellent precision. However, the longer electrolysis time is not suitable for mass production, which makes this method less appropriate than etching. The electrodeposited layer must have at least 4 µm. Otherwise, it will fracture or crack when you separate the layer from the base material.