A visit at Arduino’s Factory
If you’ve always been curious about how an Arduino board is made, we’ll lead you through the production process at Arduino’s plants in Italy. It’s going to be quite a long journey, although we’ll try and make it simple.
We’ve been, together with the photographer Marco Frigerio, who has taken pictures of the production process, to Strambino, the hometown of the Arduino boards, a couple of days ago and now we’d like to describe how an Arduino is made to all of you who are keen on learning. The very first stages, those regarding the birth of the idea of the board and its design and development, including hardware and software, will be covered in a future post.
Once the idea is ready to become reality, that is, it is decided that a board will become an effective product, the board designer prepares the layout on a Computer Aided Design system. The layout is then transferred to the manufacturing line, and it includes the copper tracking layers, the solder-masks and component notations.
The first step in the manufacturing process is the preparation of the electrical “bed” for the boards to be: a long automated process that is used to fix on inactive materials copper (to lead the current), other layers and silk print the board that is the basis for all of the other components of an Arduino.
Of course, each type of board has a different print, starting from the copper layer to be applied to inactive materials, but we may think of the process as being similar for each type of board.
The boards are combined on larger production panels, easier to handle and more efficient than working each board one by one. Several copies of the same board are therefore on the same production panel for these working stages.
The board data is transferred to a laser-printed film that is then developed and unloaded for the operator.
The inner layers of our Arduino boards are made of a panel of laminate with copper foil pre bonded onto each side.
The copper is cleaned and then coated with a layer of photoresist, a photosensitive (i.e. sensitive to light) film.
The film is loaded into the machine, then the coated panel, then the second film. Through the use of powerful UV lamps, the photoresist is hardened through the clear film to define the copper pattern of the board. Where the film is black, the photoresist remains unhardened. After this stage, the panel goes through machines that use an alkaline solution to remove the unhardened resist. Then it is washed and dried and undergoes a first control to check that everything is as we had planned.
Once the test is over, the excess copper is removed using again an alkaline solution. After etching away the unwanted copper, the photoresist that protected the copper image is removed, too, so that only the image we desired in the beginning is left.
After some other technical passages that allow adding the other layers to the initial panel, the drilling takes place and the end result looks like this:
The plating process can now start. It’s a complex process that, through a series of chemical and rinsing baths, deposits chemically a very thin layer of copper on the hole walls. The line for this part of the process is fully computerized and this passage is necessary to connect the conductors between the layers of the boards. As a next step in the process, the outer layers are imaged and then plated and etched, exactly as the inner layers.
The silk screen with the legend, the name of the company and all of the other details related to the single type of board is applied.
At the end of this printing phase, the control department electrically tests each single board on the production panel against the original board data.
At the end of the tests, the boards are profiled and cut out of the production panel. They’re then packed and sent to the next stages of production.
In the next stages the electronic parts are added to the board. The tiniest parts are on long strips that pass through machines to be added to the single boards:
They’re then soldered to the boards passing through another machine, which is just attached to the one adding the tiniest bits.
Once cooled down, they go to workers who add the larger bits manually:
The boards, still in panels, then go through another soldering machine. This heats slowly the boards, to avoid damages to the electronic components, and then solders at very high temperature the components to the board.
Once cooled down, the boards are ready for another round of testing. The first step is optical, to verify that the soldering has been done the proper way.
The second round of testing includes installation of the boot loader on the chip, so that the makers can program it via USB or how they prefer.
The final step is packaging, which is, once again, done manually, one board at a time:
If we think about the starter kit, the packaging is more complex. The single components of the kit need to be filled in small bags,
which are then weighed to understand if everything that belongs to the kit has been inserted,
and all of the bits and pieces packed and then again inserted in the Starter Kit box,
which is then sealed with a plastic film.
Ready for warehousing and shipping!
All of the manufacturing process for the Made in Italy Arduinos happens in Strambino, the headquarters of Arduino. Here a number of people work on the programming of the machines, on the machines themselves doing the production bit, and on machines testing one by one the boards in their first production step.
The warehouse is of course the core of the shipping business, where all of the boards arrive once their ready and packed, and they get delivered wherever in the world they’ve been purchased.
The warehouse also delivers to distributors, who send them to their customers.
As of today, we’ve shown you the production part of the process and the warehousing and shipping part of it.
by Silvia Bianchi