1>Mechanical engraving
This method is to use physical engraving to separate the leads and pads on the PCB from the unnecessary copper. Of course, if not so expensive
For professional equipment, you can also use a utility knife to draw by yourself, and it is still possible for some very simple circuits. In special cases, high-power lasers can also be used to engrave the copper layer of the PCB, which is suitable for some special substrate circuit boards, such as the production of ceramic substrate PCBs and aluminum substrate PCBs.
2>Chemical corrosion
The principle adopted by this category of methods is similar to the traditional PCB production process. They are all on the copper-clad surface of the PCB. The leads are covered, and then the remaining copper is removed by chemical etching to form a usable PCB.
Corrosion of circuit boards by ferric chloride where:
. Exposure method: A PCB board with special pre-applied photosensitive glue is required, and the exposure is completed using an ultraviolet lamp. After that, two steps of development and corrosion are required to obtain the circuit board;
. Thermal transfer method: just print the PCB circuit diagram on the thermal transfer paper by a laser printer, and then fix the toner on the copper clad layer of the PCB through a specific thermal transfer machine, and the required circuit can be obtained after corrosion plate;
. Inkjet printing: it is an inkjet printer that needs special modification [11, and the circuit is printed directly on the PCB;
·Oil pen drawing: the simplest, only need to use ordinary oil-based marker pen, coupled with ingenious drawing, you can.
3>Paste the circuit
For some circuits with relatively simple leads and relatively large currents, they can be pasted with copper foil tape.
4>Conductive ink
This is to add some nano-silver particles to the ink, so that the ink can dry quickly and conduct electricity, forming a conductive metal film. On this basis, it is possible to form
into the required circuit.
The advantage of the circuit formed in this way is that the required circuit can be formed on the surface of any object, but the width of the circuit is relatively large, and the resistance of the circuit is relatively large, which is suitable for making some simple control signal circuits.
5>Castle in the Air
Realize the highest state of the circuit, that is, a circuit without a circuit board. In fact, in the early circuit production, due to the relatively large size of electronic components, the circuit used leads to solder directly between the pins of the components. The current device ratio is relatively small. In special cases, removing the circuit board can greatly reduce the size of the circuit.
