Warning! This is the archived 1999 Fabweb site! Here is the latest site
3. Spin on Photoresist: Following oxidation, several drops of an expensive (>$1,000/gal.) liquid called PHOTORESIST are
placed on the wafer. The wafer is then spun at 3,000rpm reducing the puddle
to an amazingly uniform layer about 3 microns thick. (1 micron = 1 millionth
of a meter.) (We use positive PR in the ece344 process.)
4. Bake and Expose the Photoresist: After baking the wafer on a hotplate so the photoresist hardens a little,
it's exposed to UltraViolet (UV) light shining through a mask plate with
a chrome patern on it. A photosensitive component of the photoresist
undergoes a chemical change in the exposed areas, creating some acid.
This screen is maintained by
Kevin Beernink - U of Illinois ECE Dept. - beernink@uiuc.edu
E-mail comments and suggestions to ece344@uiuc.edu or use the
FEEDBACK FORM.
overview1.html
Warning! This is the archived 1999 Fabweb site! Here is the latest site