Plating process (4)

Principle of Chemical Plating

(However, the specific chemicals used, designs, and principles can vary depending on the chemicals used.)

 

Utilizing the tendency of metals to ionize, Cu ions are reduced and deposited onto the product using Pd as a catalyst.

 

Formaldehyde (HCHO) is oxidized to emit electrons on the Pd surface, supplying Cu+ ions to facilitate the deposition of Cu on the Pd surface.

 

Pre-treatment: Removes surface oxide layers and creates a favorable environment for Pd ion adsorption (soft-etching / cleaning with degreasing treatment).

 

Catalyst Treatment: Pd is adsorbed onto the epoxy resin and metalized through reduction.

 

Plating Bath: Supplies HCHO to the catalyst surface to emit electrons and initiates a reaction where Cu is deposited (deposited) on the surface by combining with Cu+ ions (chemical composition: Cu+, HCHO, NaOH).

 

Key Point: Depending on the material, there can be variations in the level of Pd ion adsorption, requiring condition adjustments according to the material. Factors such as chemical temperature, concentration, and processing time are crucial for management.

 

Detailed Chemical Plating Process

cleaner/conditioner - soft etching - pre-dip - catalyst - reducer - electroless copper

 

Cleaner/Conditioner (Degreasing)

 

Provides wetting property inside holes to facilitate attachment of catalyst particles in the catalyst process.

Removes minor oxide layers and impurities from the copper surface.

Coats conditioning agent on hole walls and surfaces.

Reinforces conditioning to achieve flawless coverage and prevent void formation.

Facilitates the removal of oxides and contaminants on the substrate surface.

Soft etching and subsequent steps will be covered in Part 5.