Developper – Pill
![Developper – Pill](https://www.epfl.ch/schools/sti/ateliers/wp-content/uploads/2019/09/Developpeuse-1024x576.jpg)
This equipment realizes the development of the photoresist. It removes the non-exposed photoresist by projecting a NaCO3 solution onto the film.
Electroplating chain
![Chaîne galvanoplastie](https://www.epfl.ch/schools/sti/ateliers/wp-content/uploads/2019/09/Chaine-galvanoplastie-1024x576.jpg)
This installation operates electrolytically and allows the following operations:
- Metallization of holes by chemical preparation and electrolytic copper
- Copper deposit of about 20 µm on the tracks and in the holes
- Deposit of tin acting as a saving when etching
Stripping – Pill
![Stripping - Pill](https://www.epfl.ch/schools/sti/ateliers/wp-content/uploads/2019/09/Strippeuse-Pill-1024x576.jpg)
Used to remove the resist covering the unwanted copper. This is done generally using soda or potash.
Etching – Pill
![Etching - Pill](https://www.epfl.ch/schools/sti/ateliers/wp-content/uploads/2019/09/Etching-Pill-1024x576.jpg)
The copper parts which have not been protected by protective tin are now etch away. For this we use a powerful alkaline solution. This process is quite critical because we need to ensure that we do not etch tracks sideways so they are exactly as requested by the designer.