Do you know the characteristics of dry film in the PCB industry?
1. It has a higher resolution. Generally, the line width can be 4mil;
2. Dry film is used in pattern electroplating process, and electroplating is carried out between the high and vertical clamping walls. hen the thickness of the plating layer is less than the thickness of the resist, the plating layer can be prevented from protruding, and the resist is prevented from being embedded under the plating layer when the film is removed, thereby ensuring the accuracy of the circuit;
3. The thickness and composition of the dry film are consistent, which can avoid discontinuities in the imaging process and has high reliability.
4. The application of dry film greatly simplifies the PCB manufacturing process, which is conducive to the realization of mechanization and automation.
The function of laminated dry film is to adhere the dry film to the rough copper surface. The film laminating machine attaches the dry film to the copper surface by pressing while tearing off the protective film on one side. In the PCB manufacturing process, PCB dry film technology usually encounters some failures. But below we introduced some common problems and solutions when sticking film on PCB.
1. The dry film cannot adhere firmly to the copper foil
(1) The surface of the copper foil is not clean, with oil stains or oxide layers. Please clean the circuit board surface again and operate with gloves.
(2) The solvent in the dry film solvent evaporates and deteriorates. Please store at low temperature, and do not use expired dry film.
(3) Fast transfer speed and low film lamination temperature. Please change the filming speed and film temperature.
(4) The environmental humidity is too low. Please keep the relative humidity of the production environment at 50%.
2. Air bubbles will appear between the dry film and the surface of the copper foil
(1) The surface of the copper foil is uneven, with pits and scratches. The lamination pressure of the film needs to be increased, and the board transport should be handled gently.
(2) The surface of the heat press roller is uneven, with pits and film drilling dirt. Please pay attention to protect the flat surface of the heat press roller.
3. Dry film wrinkling
(1) The dry film is too sticky, please place the board carefully.
(2) The board is too hot before filming. Please do not set the board preheating temperature too high.
4. Residual glue
(1) The quality of the dry film is poor, please replace the dry film.
(2) The exposure time is too long, please shorten the exposure time.
(3) The developer is invalid, please change the developer.
SHENZHEN HOYOGO ELECTRONIC TECHNOLOGY CO., LTD. is an international, professional, reliable PCB manufacturer. We have 2 production bases with a monthly production capacity of 500,000 square meters. One-stop PCB product supply and solution. And HOYOGO have a management team with 25 years of average industry experience and reliable quality assurance.