Photo Forming is a technique that combines the photo resist pattern forming (previous tutorial) and Electro-forming and/or Chemical Plating. This forming technique does not utilize any chemical etching, but uses an identical pattern forming methods as photo-resist patterning and often used in the same field where photo etching is used.

The photo-forming is a process of forming metal parts by building up electro-plating or chemical plating layers on a substrate. A photo resist is applied on a substrate to create a photo etching pattern, and by growing a thick plating layer where photo resist is void (on bear metal portion) a metal part can be harvested.

Photo etching and photo forming are compared in [Fig.1] below.

As can be seen in [Fig.1], the pattern forming techniques are the same with both processes but the substrate materials used are different. With photo etching, the resist material is applied on a metal work piece, where conductive film is applied on a substrate with photo forming. The substrate does not necessarily need to be metal. It can be insulating material such as plastic, glass, and wax where conductive film can be applied and plated. The final product is peeled off of the substrate after desired amount of plating is deposited.

Since the final product is to be peeled off of the substrate after the plating is done, the substrate surface must be pre-processed to promote ease of peeling. Commonly used substrates are made of steel, nickel, stainless steel, aluminum, copper, and brass for workability and economy reasons. These metal substrates are de-greased, pickled, and activated using the standard methods, then photo resist is applied, exposed, and developed. After the desired patterns are formed, thin film of oxide, sulfide, and chromate is deposited, then plated.