TPU Scrubbers for Fluorides Featuring four abatement stages for CVD (AP-, LP-, PE-) reactors, with fluorinated gases like NF3, XeF2, Freon ... plus insoluble metal Hydrides: typically in the selective etching processes. Like the EPI scrubbers, these units guarantee TWA emissions below 20 ppb, maintaining a programmable constant vacuum level in the reactors exhaust lines for gas flowrate variations within 0 to 100% rated values. In the first stage the incoming gas enters in intimate contact with the neutralizing solution, passing in the plate sieves turret: here, the source decomposes forming SiO2 flakes that incorporate most of the dopants. The flakes are then evacuated through the overflow liquid trap in the base tank, and the gas enters the thermodestruction section. Here the gas is first heated to 250 ÷ 400 °C, then its cracking ends at 400 ÷ 700 °C; both phases are independently programmable for insertion and temperature, as a function of inlet gas type and flowrate. The third stage is a turret with packing rings and sprayers, where the absorption of slow soluble Hydrides and Hydrochoric takes place: the remaining humid gas flow is drawn to the fourth stage. The latter is a Venturi jet ejector, fed by the neutralizing solution pump: this stage abates the residual solutes and forces the gas to the exhaust chimney.

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