| we use nmigen (python-based OO HDL) which through yosys generates verilog as an automatic step. 180nm is still by far and above the world's most heavily-used geometry, because the price-performance (bang per buck, however you want to put it) is so extremely high. an 8in wafer is USD 600 and that's extremely low. any power MOSFET, power transistor, diode or other high current semiconductor you absolutely don't want small "things" (detailed tiny tracks) you want MASSIVE ones. why on earth would you waste money on tiny features, it's like using the latest 0.15mm 3D printing nozzles to 3D print a massive 300x300x300 mm cube that's going to be used for nothing more than a foot-stool. you want a 1.2mm nozzle for that! then any processor below 300 mhz, you can get away with 180nm. need only an 8 mhz 8-bit or 4-bit washing machine or microwave processor, or something to go in a cheap digital watch? 180nm is your best bet: you'll get tens of thousands of < 1 mm^2 ASICs on a single wafer which means you're well below $0.05 per individual die. a 28nm 8in wafer would be about... 10x that cost, you'd end up with exactly the same transistor (or 8 mhz 8-bit processor), why would you pay more money for what you don't need? btw the real reason why there's a chip shortage: the Automotive industry, who are cheap bar-stewards, wanted even lower than $600 per 8in wafer so they went with 360nm and cruder geometry. that's equipment that's even older than the 1990s, like 40+ years in some cases. so then the stupidity hit, and they stopped ordering. then 18 months later they phone up these old Foundries and say, "ok, we're ready to start ordering again". and the Foundries say, "oh, we switched off the equipment, and it cooled down and got damaged (just like that massive Electric plant in S. Australia that was de-commissioned, the concrete cracked when they switched it off, and it's completely unsafe to start up again). you were our only customer for the past 30 years, so we scrapped it all. you'll have to now compete with the consumer-grade smaller geometry Fabs like everyone else". which is something that none of the Automotive companies have told their Governments, because then they can't go crying "boo hoo hoo, we can't make chips any more at the price that we demand, waaa, waaaa, i wannnt myyy monneeeeey" and now of course they can't use the old masks, because those were designed for 360nm and cruder geometries, they have to redesign the entire ASIC for 180nm and that's why you can't now get onto 180nm and other MPW Programmes because the frickin Automotive Industry has jammed them all to hell. |