# sky130

Connie Duong

04/27/2022, 4:37 PM
Hi, are custom devices allowed on the skywater pdk such as photodiodes? I understand it probably won't be extracted properly in the ext2spice commands, but is it still able to be fabricated if we follow the design rules for sizing of the individual layers? Thanks!

Tim Edwards

04/27/2022, 6:14 PM
The photodiode is a known characterized device and is available in the parameterized device menu in magic, and extracts properly as a photodiode.
The only problem with the photodiode is that it is not really compatible with the Google-sponored open-MPW, as that MPW run gets post-processed with bump bonds, and the chip is expected to be mounted upside down on a board. It would be appropriate for the ChipIgnite run. If you (or anyone) has a design that makes use of photodiodes, we can probably get it put on a ChipIgnite run. You would want to make sure you get bare die back, because even the ChipIgnite projects by default are wirebonded into (opaque) QFN packages, and you would want to have it wirebonded into an open frame package with a removable lid.

Connie Duong

04/27/2022, 6:27 PM
@User Thanks for the reply and advice! Can I find the photodiode characteristics in this document for the skywater pdk ? I only was able to find diodes in the skywater pdk; is the parameterized device menu in magic separate from the pdk files/libraries?