High-Pressure, High-Flow Purifier

The high-pressure, high-flow Hydrogen Chloride (HCl) Purifier is designed to be installed in the flow train of an HCl Bulk Specialty Gas System (BSGS)- to deliver extremely dry and consistently pure HCl into an electronics manufacturing facility.

Bulk HCl is used in various semiconductor processing operations, such as cleaning susceptors and pre-clean for oxidation processes. It is also used in dry etching of silicon, polysilicon, and gallium arsenide layers prior to epitaxy. The degree of dryness of HCl is considered critical to the quality of semiconductor devices, since moisture contamination at low parts-per-million levels in HCl can cause problems, both in the gas distribution system and in the manufacturing process. For example, in cleaning susceptors, water contaminants in HCl can result in the formation of undesired oxide on the susceptor. In etching applications, a trace amount of water can lead to a sudden loss of etch selectivity. A purification system can be employed to effectively remove moisture contamination in the HCl gas stream. It also precludes any downtime or other issues that may occur during container changeouts.

The Purifier, with load-bearing capability for a maximum HCl flow of 1,200 SLPM, not only minimizes moisture contamination, but also ensures a consistent moisture level in the HCl delivered, reducing the variation from trailer to trailer and tube to tube. The Purifier also reduces the variation caused by vaporization of the liquid HCl inside a container. With a maximum operating pressure of 2,000 psig at 50 degrees Celsius, the HCl Purifier is a 28" long by 4.5" diameter vessel with 0.5" VCR(R) inlet and outlet connections. The Purifier media are contained by 20 micro filters at the inlet and outlet.

Air Products and Chemicals, Inc., 7201 Hamilton Blvd., Allentown, PA 18195-1501. Tel: (610) 481-4911. Fax: (610) 481-5900.