[bArray]

> Those with a bit of silicon savvy would note that it’s not cheap to produce such a chip, yet, I have not raised a dollar of venture capital. I’m also not independently wealthy. So how is this possible?

What kind of order of magnitude of cost are we talking about?

What are the next steps - is there some service to cut the wafer and put into a package for you?

[bunnie]

The masks alone are single digit millions, but with all the design tools and staff costs typically tens of millions is the benchmark number for a tape out in this node.

After coming out of the fab, the chips go through probing, packaging and reeling.

[eqvinox]

> The masks alone are single digit millions,

Ah, another reason why hardware erratas get fixed so rarely (I assume - along with retesting of course).

[drob518]

Yes, exactly. A lot depends on your expected volume. Essentially, masks are your fixed tooling cost for chips. You then amortize that over your full volume. It’s easier to justify another mask set to fix bugs if you are going to be selling oodles of chips and the cost ends up being negligible and much harder to justify it if the volume is low. Years ago, I was CTO at a startup when our chips came back from fab. Everything looked good except for a silly error that our chief architect had made. He felt horrible for a couple weeks. He was a great architect (meticulous and precise) and I kept telling him that it was no use crying over spilled milk. Engineering is hard. But there went another few million dollars of precious venture capital up in smoke for the replacement mask sets.

[eqvinox]

I knew the masks were expensive, but not that they were that expensive. Of course it's all a question of total quantity you use that mask for, but still...

[bunnie]

It all depends on the node. Masks in 130nm are maybe in the $10k's-$100k's range. Masks for the latest TSMC nodes might cost you $30-40 million per set. The masks are pretty much a modern marvel in their own right - I'd wager they are some of the most precisely manufactured human objects in existence.

[pjc50]

Most chips have basically one revision after first tapeout, because it's hard to get everything right first time. Small revisions can sometimes be done in the metal layer only, which is cheaper.

[crote]

Can you share something about the subsequent per-chip manufacturing costs?

[bunnie]

Rule of thumb is that a processed wafer from 28nm and older is around $3k/wafer and the cost goes up kind of exponentially towards the smaller nodes. Also, in general, the fab wants you to order a "FOUP" of wafers at a time - that's 25 wafers at a go.

[bArray]

So a little out of the budget of a hobbyist!

Is there a service to get on a FOUP with a group of people? I know for example of Tiny Tape Out [1], but I'm wondering where you might explore for larger designs.

[1] https://tinytapeout.com/