how is a pcb manufactured step by step2020-08-08
how is a pcb manufactured step by step
Today, we will play a unique role for ourselves. We will not talk about gadgets, but about the technology behind them. A month ago, we were in Kazan, where we met guys from the Shenzhen campus. At the same time, we visited the nearby (relatively close) PCB manufacturing factory miraclepwb. This article is trying to understand how to produce the same printed circuit board. So, how to make a printed circuit board for our favorite gadget?
The factory knows how to make circuit boards from start to finish-design circuit boards according to your technical specifications, manufacture fiberglass, produce single-sided and double-sided printed circuit boards, produce multilayer printed circuit boards, marking, inspection, manual and automatic assembly, and soldering Circuit board.
First, I will show you how to make a double panel. Their technical process is no different from the production of single-sided printed circuit boards, except that the second side is not operated during the OPP manufacturing process.
About PCB manufacturing method
Generally, all methods of manufacturing printed circuit boards can be divided into two major categories: addition (from Latin addition-addition) and subtraction (from Latin subtraction-subtraction). An example of subtraction technology is the well-known LUT (Laser Ironing Technology) and its variants. In the process of using this technology to create printed circuit boards, we use the toner in the laser printer to protect the future trajectory on the glass fiber board, and then ooze out all the unnecessary things in the ferric chloride.
In contrast, in the add-on method, conductive traces are applied to the dielectric surface in one way or another.
Semi-addition (sometimes called combined method)-a cross between classical addition and subtraction. In the process of producing PCBs using this method, part of the conductive coating can be etched away (sometimes it is corroded almost immediately after coating), but generally, this is faster/easier/cheaper than the subtractive method. In most cases, this is due to the fact that most of the thickness of the track is formed by electroplating or chemical methods, and the etched layer is very thin and only serves as a conductive coating for electroplating.
I will show exactly how to combine.
Use positive composite method (semi-additive method) to manufacture two-layer printed circuit boards
Glass fiber manufacturing
The process begins with the manufacture of foil-clad glass fibers. Fiberglass is a material composed of glass fiber sheets (looks like dense, shiny fabrics) that are impregnated with epoxy resin and laminated into one piece.
Fiberglass canvas itself is not too simple-they are woven with thin glass threads (just like ordinary fabric on shirts). They are so thin that they can be easily bent in any direction. It looks like this:
It’s too long, I have to sew this photo from a few frames. This is a Swiss machine from Posalux. Unfortunately, I don’t know the exact model. According to its characteristics, it is close to this. It consumes a three-phase voltage of 400V, which is three times that of a three-phase power supply, and consumes 20 kW during operation. The weight of the machine is about 8 tons. It can process four batches simultaneously using different programs, which provides a total of 12 plates per cycle (naturally, all workpieces in a batch will be drilled in the same way). Drilling cycle-from 5 minutes to several hours, depending on the complexity and number of holes. The average time is about 20 minutes. Technotech has three such machines.