The PLADE solvents bench is used for development of ZEP and MMA/PMMA resist, for lift-off process using acetone, and for cleaning of the spin coater chucks, tweezers, and ZEP and MMA/PMMA glassware. It is located in the processing room of the ebeam zone (zone 7), and is dedicated to ebeam lithography ONLY !!! Following resists and solvents are currently authorized to be used there: MMA, PMMA, ZEP, CSAR, Acetone, IPA, MiBK, n-Amylacetate. Please do not bring in any other material and do not try to process any other resist or substance there. If you have any special request, please, talk to Zdenek first.
To use the solvents bench, you must were additional protective gloves.
High level solvent warning light
All waste solvent that is poured down the bench (through the steel metal grid of the bench top surface) is collected in a 10L waste canister under the bench. When the canister is full, the warning red light “HIGH LEVEL SOLVENT” lights up. Please, notify CMi staff immediately and DO NOT USE THE BENCH WHEN THE RED LIGHT IS ON !!! Anything you pour down the drain from this moment on will result in overflow of the waste tank!
Disposal of waste acetone after lift-off
The solvents bench serves as a safe place to carry on lift-off process with acetone in smaller or larger glass beakers. All beakers need to be properly sealed to prevent the acetone from evaporating, and they need to be labeled with users name and with a date. Please, do not disturb beakers of others, and do not keep your own process going for longer than necessary. Clean as soon as you are done with the lift-off. DO NOT FORGET to rinse your wafer with IPA after you remove it from the acetone bath before you dry it!
To clean the glass beaker DO NOT pour its acetone content down the bench. The glass beaker contains plenty of lifted off metal as well as the acetone, and the metal would inevitably clog the bench pipes. To empty the glass beaker, use the plastic canister standing next to the solvents bench. Remove the black cup, place in a large funnel (available on the bench next to the canister), pour the content of your lift-off beaker into the canister via the funnel. Afterwards rinse off the beaker with acetone and IPA on the bench, dry it with nitrogen gun, and place it to the white plastic try with the “dirty” glassware. Remove the funnel and close the canister with the black lid.
Empty bottles and use of sonicator
Place any empty bottles into the white “EMPTY BOTTLES” tray on the top of the coater.
Sometimes, it may be advantageous to use the sonicator/heat-bath to facilitate the lift-off process. Please, do not leave the room while using the heat-bath/sonicator. If you need to re-fill the water in the sonicator, use DI water from the water bench and some unlabeled glassware from the top right shelf of the nitrogen dry cabinet.