Yes there are services where you can get custom ICs made - they’re called ‘multi project wafer’ services. They start around $10K (e.g. efabless does one about that much with the SkyWater 130 nm proces) which is pretty good given how much it costs to do the lithography, not to mention actually making the ICs!

But in general it’s a very difficult process. The cleanliness required, the scale at which all this happens, etc. are just orders of magnitude harder than a regular PCB. That’s not even considering the nasty chemicals needed to etch silicon which are way worse than PCB etching chemicals!