EBARA 80?25 Installation Operation & Maintenance page 38

EBARA Multi-Stage Dry Vacuum Pumps
service representative for assistance in determining the appropriate inspection and
cleaning interval.
Process
Metal Etch
SiN (PECVD)
SiN (LPCVD)
TEOS /SiO2
Asher
Cleaning
Cooler cleaning involves removing the coolers from the pump and soaking the coolers
in water or weak acid solutions (depending on the process) to dissolve away any
chemical deposits. Down-time can be minimized by having a set of exchange coolers
available. Coolers can be removed and reinstalled in about 2-3 hours.
After soaking, the coolers need to be leak-checked using either a Helium leak test,
Hydrostatic leak test using 10.5 kgf/cm
compressed air to the cooler tubes. After the soundness of the cooler tubes is
confirmed, the coolers should be dried in an oven.
The following list summarizes the recommended cooler cleaning procedures for several
common semiconductor processes. If not listed below, please contact the local Ebara
service representative for assistance in determining the appropriate cleaning procedure.
Aluminum Etch Processes: Clean the coolers by soaking them in water for 2-3 hours.
PECVD Processes: Cooler cleaning can be accomplished without removing the coolers
form the pump. Remove both end caps from each cooler and remove the loose
powdery chemical build-up using a vacuum cleaner.
WARNING
!
Wear protective gloves when performing maintenance on the coolers. Review
safety precautions to be taken when using HF Acid before attempting to clean the
coolers.
Nitride LPCVD: For Nitride LPCVD service, the coolers should be examined after two
months of service. Clean the coolers by dipping them briefly in a 5-10% solution of HF
acid and then rinsing them in water. Continue this process until the process chemicals
have been completely removed.
The coolers can be damaged if they are left in the solution for any extended
length of time.
930601-P
Recommended Interval
3 - 6 Months (a function of chemistry)
2 - 3 Months
2 Months
Cooler Cleaning normally not required
Cooler Cleaning normally not Required.
2
(150 psi pressure), or immersion in water with
Pump Maintenance
30