Once a chip design is complete, it is taped out for manufacturing.
This means sending the GDS2 files to the foundry.
The term “tape out” was coined in 70’s. There are 2 theories from where the name comes from:
- Early ICs were made in a very similar process to PCBs, where sticky tape was used to create the shapes, followed by shrinking the design down with an optical photograpy process.
- ASIC design files were stored on magnetic tape. The event of carrying out the tape to the foundry was thus called “tape out”.
I now have pretty good evidence that #1 is the correct answer, as I’ve spoken to people who were designing chips in the early days of VLSI and they used paper tape before magnetic tape.
I think the reason #2 got popular was because it was described this way in an influential (and highly recommended book): CMOS/VLSI design by Weste & Harris.
So far we have made 4 tapeouts:
Matt Venn's Zero To ASIC course is a real eye-opener to the possibilities of open source hardware. The course itself is a tour-de-force overview of almost all aspects of ASIC development from concept to GDSII. It's also great fun and regardless of your background or previous experience, you'll learn a lot and have a great deal of fun doing it. This course has inspired me to take the next step and submit my own design to efabless.