But it's not just about cost, the amount of extra resource -- meaning, engineers! -- needed to support both BSPD and FSPD processes is huge because so many things are different. For starters the layouts are completely different so all IP (both internally and externally sourced) has to be rebuilt from scratch, and it's not just a few layout tweaks it's a major rethink -- plus the extraction is different, thermal properties are very different, libraries (standard cell and SRAM) have to be redone from scratch, tool costs double, customer support effort doubles. You also have to duplicate all the process qualification/reliability analysis because the processes are physically fundamentally different, and this alone is a massive effort and takes a lot of time and wafers to do.Not sure I agree with the logic here. Intel's biggest need right now is to fill the fabs. Choosing not to even try to serve a large portion of the potential market doesn't seem like a winning prospect to me. Yes the upfront expense is high, but the cost of underutilized fab space is astronomical. Just like interest, the cost of unused fab space never rests, it just keeps sucking up money.
Intel's plan is for these new nodes to run for over a decade plus. That is a lot of time to recover the upfront investment. I think being too concerned about a short term up front cost is short sighted and will cost Intel more in the long run.
I also don't think Intel wants to paint themselves out of the picture to manufacture the designs that their new ASIC design business will potentially generate. With BSPD being primarily aimed at HPC applications it seems to me front side power will be more desirable for many ASIC applications. Including the option in the foundry offerings gives these ASIC customers an easy on-ramp to work with Intel foundry.
Intel are already likely to be stretched in all these areas just to support BSPD because traditionally they only had to support internal design teams (so crappy documentation is "OK"), much more effort/resource is needed to properly support external customers -- been there in the past, got the T-shirt. Suggesting that they could easily do all this again for FSPD is not credible, they'd end up with terrible support for both processes instead of barely adequate support for one -- TSMC have being doing all this for years on multiple processes, but that doesn't mean Intel can do the same...
It doesn't matter how much Intel might *want* do support both, the question is whether they *can* support both -- and I don't think they can, at least not today.
There's also the question of why they would realistically want to do this, because all the things that FSPD customers are looking for -- fast TTM, strong IP ecosystem, low cost, high yield, high density, quick TAT -- are the things that TSMC is *very* good at (which is why everyone uses them) and Intel is historically bad at (and still not competitive today). Fighting an opponent on a battleground where they're strong and you're weak is never going to end well... :-(
People who don't understand the huge differences between the two processes are grossly underestimating the cost and difficulty of supporting both, see post from @MKWVentures above... ;-)
