PCB Tech - Process flow for making circuit board

circuit boardmaking process: trimming board peripheral dimensions--duplicate--drill hole positioning--sticker--corrosion--cleaning--de-glue--fine sandpaper polishing--rosin.

1. First polish the surface of the copperplate that meets the size requirements with fine sand paper, then copy the wiring diagram onto the copperplate with the copperplate paper.

2. Drill holes and locations with a 1.0 mm diameter drill, then apply glue (or paint).

3. After gluing, place a thick sheet on the board and press it with your palm. The purpose is to make the whole glue stick to the copper clad plate more firmly. When necessary, the dryer can also be used to heat up, and the viscosity can be enhanced by using the right glue. Because the glue used is very sticky and the glue paper is thin, this kind of glue can be used to make boards with good results, generally without heating treatment.

4. Ferric trichloride is generally used as the corrosion liquid. The corrosion speed is related to the concentration of the corrosion liquid, temperature and dithering during the corrosion process. In order to ensure the quality of plate making and improve the corrosion speed, dithering and heating can be used.

5. After the corrosion is finished, rinse it with tap water, remove the adhesive paper and dry the printed board.

6. Rub the copper-clad surface of the printed board with a fine sand cloth until it is bright, and then immediately coat it with a rosin solution. (When applying rosin fragrance, tilt the printed circuit board and put it on the wall before applying rosin fragrance to prevent the rosin from flowing through the holes to the back).

Notes: (1) Rose perfume is used to prevent oxidation, aid welding and increase the brightness of solder joints, etc. Rosin solution is made of rosin powder mixed with alcohol or Tianxun water in a certain proportion, and its concentration should be moderate, so that it can feel a certain stickiness.

(2) Ferric trichloride solution has no adverse effect on human skin, but if it is found on clothes or on the floor, it is difficult to wash it off, so special care must be taken when using it.