FPC flexible circuit board etching process

Principle: Etching is a process in which an etching solution is uniformly sprayed onto the surface of a copper box through a nozzle under certain temperature conditions (45, 45). The solution undergoes an oxidation-reduction reaction with steel that is not protected by an etching inhibitor, and the unwanted steel is removed from the surface. The substrate is then exposed and treated to form a circuit. The main components of etching solution are copper oxide, hydrogen peroxide, hydrochloric acid, and soft water (with strict requirements for clarity)

Quality requirements and control points:

1. There should be no residual copper, especially on double-sided panels, which should be taken into account.

2. There should be no residual adhesive present, otherwise it may cause exposed steel or poor adhesion of the coating.

3. The timing speed should be appropriate, and it is not allowed to have line changes caused by excessive etching. The timing line width and total pitch should be the focus of this station's control.

4. The dry film on the solder joints of the circuit shall not be separated or broken by punching.

5. After peeling the film at all times, the board must not have any oil stains, impurities, steel peeling or other poor quality.

6. When placing the board, attention should be paid to avoiding jamming and oxidation.

7. It should be ensured that the distribution of the medicine solution is uniform at all times to avoid uneven etching of different parts on the same side or front.

Brushing process control parameters:

Temperature of the sword etching potion: 45/-5C solubility of hydrogen peroxide; 1. 952050mol/L shaving solution temperature ↓ 55/-5C safe use temperature of etching machine 55C drying temperature: 75/-50 front and rear plate spacing: 5 ^ 10cm

Specific gravity of copper chloride solution: 1.2~1.3g/cm3, plate angle. Guide plate. The switch status of the upper and lower nozzles. Hydrochloric acid solubility: 1.9 205mol/L

Quality confirmation:

Line room: Etching standard line is 2rm & 0. 25m. After etching, it must be within -0.02m. Surface quality: There should be no wrinkles, folds, scratches, etc.

Check for no residual copper by following the light.

The circuit cannot be deformed