Inner layer dry film is the process of transferring the inner layer circuit pattern to the FPC circuit board, including several key steps: inner layer film, exposure and development, inner layer etching, etc. Specifically, the inner layer dry film is a special photosensitive film attached to the surface of the copper plate. This film will solidify when exposed to light to form a protective film. During the exposure and development process, the transparent part is solidified, and the non-transparent part is removed, and finally the circuit pattern is transferred to the board through etching.
Process flow of inner layer dry film
Inner layer film: A special photosensitive film is attached to the surface of the copper plate.
Exposure and development: Expose the board with the film attached, the transparent part is solidified, and the non-transparent part is removed.
Inner layer etching: Etch the board with the cured protective film and transfer the circuit pattern to the board.
Defilming process: Remove the uncured dry film to complete the transfer of the circuit pattern.
The role and importance of the inner layer dry film in the manufacture of FPC circuit boards
The inner layer dry film plays an important role in the manufacture of FPC circuit boards. It ensures the precise production of conductive patterns through the pattern transfer process, which is the basis of FPC production. When designing wiring, it is necessary to consider the control of the minimum line width, spacing and the uniformity of wiring to ensure safe spacing during production and avoid problems such as short circuits or open circuits.
The relationship between the inner layer dry film and other manufacturing processes
The inner layer dry film is closely related to other manufacturing processes such as HDI board manufacturing. HDI boards use laser drilling technology to make the line distribution more dense, adapting to and promoting the development of the PCB industry. The process flow and quality control of the inner layer dry film are crucial to the manufacture of HDI boards.
