Okay, I'm trying to replicate a diode structure, but it seems to violate the DRC so I must be doing something wrong. The diode consists of a P substrate followed by an N-Well, and finally an N+ on top of the well. I'm assuming the N diffusion layer is the N+ implantation layer. I'm getting DRC error diff/tap.9, n diffusion spacing to n well < 0.34uM. Is there a different layer for N+ implantation were supposed to use or something? Because a lot of PMOS cross sections I've seen have the N+ embedded in the N-well, is it just something the foundry can't do with sky130 pdk?

"N+ in nwell" and "P+ in p-substrate" are called "TAP" in sky130 and differentiated from "DIFF" which is "N+ in p-substrate" and "P+ in nwell". Magic has always made this distinction, plus it always distinguishes between N-diffusion and P-diffusion. So there are four types of diffusion in magic, called "ndiff", "pdiff" (corresponding to "DIFF" in sky130), and "nsd" and "psd" (corresponding to "TAP" in sky130). However, magic also creates different types for extraction of devices, so that if you are trying to create a diode that will be extracted as a diode device, you should use the "ndiode" layer (or "ndiodelvs", "nndiode", or "mvndiode", depending on what you're trying to achieve). Or you can use the parameterized device generator to create a diode structure for you.

Thanks. Is there some kind of legend or something for these names? I can't find Via1 or 2

Names appear in the title bar when you have the mouse pointer over the associated icon in the icon bar on the right-hand side of the layout window. Magic can have multiple aliases for a layer name, and only the first one in the tech file shows up in the title bar. So you would see

m2contact

instead of

via1

, for example.