PCB circuit board design to engage people to understand that design is a product of the highest things tech . Design board considered the most troublesome cases making processes. While all this trouble thing to the manufacturers, but each time the plate are required to wait for a three to seven days , the time not too long, because this new design inspiration often tedious and abandoned.
Let me introduce fast -plate approach it, Rapid Banzhu have two methods of physical and chemical methods . Physical methods : by using a variety of tools and power tools , hand the unwanted copper circuit board carved out. This method is laborious and low accuracy , only a relatively simple circuit can be used.
Chemical: by a protective layer covering the blank CCL, where the caustic solution to remove unnecessary copper etched , the method is currently used by most developers . Protective layer covering a variety of methods , mainly the traditional manual method described paint , paste stickers customized approach , methods, and thermal transfer printing photographic film PCB board method was developed in recent years .
Physical methods : the traditional method of physical carving process is relatively simple, just hand-carved and drilling can be. But because all manual operation, its main drawback is laborious and time-consuming , difficult to control the precision drilling is difficult to align the two- panel , and there is unrecoverable , the operator demanding. Currently, the traditional physical methods have rarely been adopted .
Chemical methods: process is relatively complex, but the precision is controlled , is currently the most widely used method for rapid system board . The main problem is :
a. Print accuracy depends on the accuracy of printer ink cartridges used . Poor performance of the printer to print out the uneven lines , the corrosion process is likely to cause breakage , adhesions.
b. Photographic plate exposure and development time is not easy to control , and each batch of plates optimal exposure time will be different , you need to master through repeated trials .
c. High corrosion process difficult to control : a monolithic plate corrosion impossible with mass production line factory specialized control equipment used , and the temperature of the etching solution , concentration, pH will have a greater impact on the quality of corrosion . Want to do a circuit board , there must be many times the accumulation of experience . Otherwise, the material is scrapped very serious.
d. Photographic plates for higher environmental requirements must be stored under low temperature conditions all black , the exposure process must be carried out under darkroom conditions .
e. Silver ( photosensitive material ) and copper ( corrosion products ) are toxic , corrosive process operation to be very careful , personal or stained clothing difficult to clean , and because of environmental reasons , the corrosion of waste treatment is too much trouble .
f. Etched out of the finished board must use the manual work, and hand punch to control precision is difficult.
From the aspect of the finished plate adhesion to compare :
Chemical etching method because it is the entire board soak in solution corrosion, must be cleaned and dried after etching . In this process , the board after a hot and cold , wet thousand one , greatly affects the adhesion of the copper , the debugging process may be due to experimental electronics components caused by changing different parameters of copper stripped off. The method eliminates the need for physical engraving process . Thus , the physical aspects of carving methods in the adhesion properties of the finished board is better than chemical etching .
Compare the lines from the edge : the chemical etching method to make circuit boards, due to the characteristics of dissolution , the lines can be seen under a microscope, inverted trapezoidal cross section , irregular edges. The physical carved out of the lines under the microscope cross-section of a positive trapezoidal knife edge angle and the angle of the same , good linearity. This is another example of the method is better than the adhesion of physical chemistry .
From the finished plate precision comparison: the traditional physical methods because it is full manual operation, accuracy is difficult to control , can only produce relatively low accuracy and less complex circuit board . The chemical methods due to the help of many devices , the accuracy can be basically guaranteed.
From the production speed comparison: traditional carving methods of physical and chemical methods produced a similar plate , used almost the same time .
