Handling Ultra-Pure Chemicals with Teflon®
According to Interox, supplier of semiconductor grade H202, in 1993 semi-conductor manufacturers began to shy away from PVDF piping systems for handling ultra-pure chemicals.
The trend pushed toward Teflon. Interox tested Halar samples in their lab for stability. If the test proved acceptable, Interox would replace Teflon diaphragm pumps with Vanton centrifugal pumps.
It should be noted that Interox tested a Vanton PVDF Shaft sleeve and found it was acceptable (stability maintained for period of test) but because of the industry trend and some conflicting public data which indicated that PVDF may shed traces of Florine over the long run, selected the Halar instead.
AMD a national producer of semiconductors placed ECTFE on its “marginally acceptable” list. AMD also wants to replace throbbing, noisy, vibrating, air operated diaphragm (AOD) pumps with quiet, smooth operating centrifugal pumps.
AMD’s ideal pump at the time was a fully Teflon mag drive pump, with Teflon coated magnets and rear casing.