Copper thickness 4.5oz aluminum substrate, manufacturing will encounter the following problems:
1. Engineering design width compensation: copper thickness, certain width compensation, or line width tolerance after etching, which is not accepted by customers, empirical heap of line width compensation value.
2. Uniformity of printed solder: Since the copper thickness of the etched line is beyond the conventional mode, printing solder is very difficult, no, too thick, too thin, the client does not bear. How to print a layer is also this green difficulty.
3: During etching, it is necessary to etch the line width to meet the needs of customers. Copper is not allowed, and there is no knife scraper, which scratches the insulating layer, and thus leaks sparks during the pressure test. ? 4. Mechanical processing: drilling aluminum plate, but no burr is allowed in the drilling, which will affect the pressure test. Processing and appearance are very difficult. Punching requires the use of high-end molds. What is the mold manufacturing? This is a difficult aluminum substrate. Brief introduction, the marginal requirements are very neat, no burrs, no contact with the welding board edge. Cao Bing's general use, punching lines, drawing shapes from the aluminum surface, the punching force of the circuit board is reduced, so prompt. Stamping, plate bending should be less than 0.5%.
5. The entire production process does not scratch the aluminum base: the aluminum base will change color through contact, or through certain chemicals, and the black appearance will definitely not be accepted. Some customers who polish the aluminum surface are unacceptable, so the entire The process is unharmed and does not touch the aluminum-based surface is a difficult production of aluminum substrates. Some companies use passivation technology to apply a protective film to each before and after hot air leveling (HASL) ... There are many methods, eight immortal crossing the sea, each showing their magic.
6. High voltage test: 100% high voltage test is required for the aluminum plate of the communication power supply, some customers require DC, AC voltage requirements, 1500V, 1600V, time 5 seconds, 10 seconds, 100% PCB test. Dirt on the surface, pores and jagged edges on the aluminum base, wires, and any point on the block insulation will produce high voltage test, leakage current, and breakdown fire. The pressure test board layer, foamed, was rejected.
