Wet bench dedicated for Piranha (H2SO4+H2O2) wafer clean. Use only the quartz bath for Piranha clean! The standard composition for Piranha is sulfuric acid:hydrogen peroxide 3:1.
Piranha solutions are used to remove organic residues from substrates. Piranha solutions are extremely energetic and may result in explosion or skin burns if not handled with extreme caution. Use correct PPE!!
The set point of the temperature regulator is 100 °C at the moment, max is 120 °C. For the standard composition the temperature might rise up to >150 °C! So, actually heating is not neccessary. Or if using the composition 4:1, temperature rise to ca 110 °C, which is normally sufficient.
It is important to fill up with H2SO4 first and add the H2O2 afterwards. Typical amounts are 4,5 litre H2SO4 and 1,5 litre H2O2 (will cover 6") or 4 litre H2SO4 + 1 litre H2O2 (will cover 4"). Chemicals must be manually loaded, and also manually drained using the aspirator. It is important to let the bath cool down for many hours (over night) before draining, the bath temperature must be lower than 70 °C.
Contact the tool responsible before use to make sure that the bench ventilation timer is set for 24 hours. Rinsing bath includes variable N2 bubbling. The rinsing bath has only place for single or few wafers, not full 4 or 6" wafer carriers!