200 microcomputers in 3 hours, or small-scale production of microelectronics in Shenzhen (on the example of the VoCore project)

Everyone knows that China is the world leader in electronics manufacturing. We use this electronics daily. But how is it produced? I think many would be interested to look at this "kitchen" from the inside - how does the "preparation" of this electronics in reality.

With the help of this post, we will visit a real factory (one of several hundred in the city), which is engaged in the production of micro-electronics in the city of Shenzhen. We will see the stages of production - we will see the transformation of ideas from schemes and files into a ready-to-use board - a microcomputer.
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This microcomputer is a VoCore project, about which we just recently talked about - a microcomputer the size of a coin (25x25 mm) with Wi-Fi and Linux (OpenWRT).

Well, the workers were waiting for us, let's start.

Brief prehistory about the manufacture of boards

To communicate with workers in the same language (that is, to understand what they generally do), a small excursion about the production of electronic circuit boards.

VoCore project

Let me remind you that on the crowdfunding service indiegogo from May to June 2014, there was a campaign to raise funds for the VoCore project - the campaign was successfully completed (almost 3000 contributors), and VoCore is now released in the release version - and the production and expulsion stage begins.

That's how we are witnessing the production of these VoCore.

Production

The full production cycle includes the following steps (we consider SMD production technology, that is, surface mounting):

1. Manufacturing of printed circuit boards (PCB)
2. Purchase of all necessary components (BOM)
3. Making a stencil for solder paste (mask)
4. Applying paste through a stencil to the PCB
5. Installation of components
6. Oven (for melting pasta)
7. Control

The factory itself is a large room with a set of various equipment necessary to perform one of the stages in the technological production cycle.

The beginning of the usual working day in Shenzhen - workers come to the factory


Well, when the working day begins with a smile :)

Small workshop


By the way, in the white coat on the right is Wu Tong - one of the participants of the VoCore project (the founder is Qin Wei - Vonger ).

Board making

The first step should be the manufacture of the PCB, but in our example the PCBs have already been manufactured.

Solder paste application

Meet - this is GKG G5 - automatic screen printer . His task is to apply the solder paste through a stencil (in which sootv. Holes) on the pads of the printed circuit board.



Solder paste - this is what components will eventually be soldered to the board. The composition also includes solder, flux and tackiness agents. In the case of surface mounting, solder paste applied to the contacts on the board ensures gluing of the SMD components to the board, and after heating, the resins (flux, adhesive components) evaporate (after completing their task), the solder melts — wets the contacts of the component and the board — and freezes pin connection and mounting component on the board.

In order for the paste to be placed on the contact pads, a stencil is pre-made (in the photo above, the worker applies printing paste to the stencil).

The distribution of pasta on the stencil


This is what happened (below is our PCB, with 10 VoCore boards - two rows of five):


Stencil thickness is a fraction of a millimeter (it is exactly this height that the paste will be on contact pads after removing the PCB from the stencil).

And running ahead (when there will be a stove) - you can watch this video (29 seconds) to understand how this “solder paste” is transformed - into solder.


After automatic application of the paste, a printed circuit board (with freshly applied paste on the contacts) leaves the screen printer and goes to the neighboring machine (from left to right) through the conveyor:


And on the right we have the most interesting thing - a surface mounting robot.

Automatic assembly of components

Well, this is the most interesting stage - when the robotized system arranges components (sometimes smaller than a millimeter) - on the board, on contact pads (where printing paste is already located) - and the components are glued to the pads on the paste.

Meet in the photo (top left) - automatic installation of surface-mounted components . By sledding, it is fed to the board, onto which the robotic system installs SMD components, from reels of tape. By the way, such machines are installed one by one by conveyor - if the number of components is large - then they are installed on the next one (from its reels).



In the photo above - the system performs positioning according to the board.



In the work zone of the robot - go "telegraph tapes" - on these tapes are placed the components that are placed on the board.



After placing the elements on the board, the next stage is the stove.

Ready for the oven:

Stove

Here we come to the final process - get acquainted - this is JT NS-800 reflow oven - in our furnace for reflow of soldering paste . A conveyor board with installed components on it is fed to it and it is necessary to ensure the temperature for melting the solder paste.

[pay attention to the rack cartridges with reels SMD components]

Our freshly baked bread is our ready pay.


After the stove fees fall into the hands of Chinese girls to sort

Control

At the end of production - there is a visual inspection of each board. Let's pay attention to the antistatic bracelet - without this it is better not to work with microelectronics in production.

Finished result

Here is the result of the whole process! In 3 hours a batch of 200 VoCore pieces (20 slats) was made.

Together

And now you can combine everything together. In fact, the whole process runs along the same line, starting from the screen printer with printing paste, then several surface-mounted robots, and ending with the stove and control.

Here is a combined photo, and the arrow shows the direction of the process:

Application Form

Recall that we have an idea to order the manufacture of VoCore in a factory (possibly the same one) - for a small batch for Russia - in this regard - if you are interested in a microcomputer - then check our questionnaire .



Also, if you have an interesting project based on OpenWRT, then you can participate in the contest and get VoCore for your project right now free of charge - the terms and conditions of the contest are indicated at the end of the article (we will accept applications until October 12).

Thanks

Once again, thanks to targence for providing the photos.