For ESD, you might implement an N-Diode by placing an n-well in the p-sub A P-Diode by placing a P-diff within an N-well (within P-sub). But this isn’t a rule, you can make both in poly too. Another definition of N-diode and P-diode is whichever terminal is more heavily doped (matches ESD requirement)

Hey Anthony! I just came across this message in the thread. Can you please help me understand how to make a polysilicon diode in the SKY130 process? I am trying to figure out which layers I need to use to create the layout of this diode. I have inserted a figure of what I am trying to achieve below.Best, Shubham