Photoresist
From Applied Optics Wiki
Photoresists are used to coated and pattern substrates. They are normally spincoated and patterned by exposing to UV light in the mask aligner (through a mask).
They come in postive and negative varieties. In a positive resist holes are made in the film where it has been exposed to UV light, in a negative resist holes are made where it hasn't been exposed to UV light.
The following resists are used in the Fab Lab:
PMMA negative
BPO positive
