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20 August 2009


Johnson Matthey ships hydrogen and nitrogen purifiers for PV manufacturing

Johnson Matthey of West Chester, PA, USA, which designs and manufactures bulk and point-of-use hydrogen and nitrogen purifiers, has recently shipped several palladium and getter purifiers that should enable further advances in photovoltaic (PV) manufacturing.

“These latest shipments reaffirm our commitment to support the ongoing growth of the global electronics industry, particularly the rapidly expanding demand for PV applications,” says Stuart Bestrom, sales manager for Johnson Matthey’s Gas Purification Technology (GPT) group.

A major North American semiconductor company is using JM HP Series V-purge purifiers to support its diversification into indium nitride (InN) high-efficiency solar cells. A purifier is installed on each MOCVD reactor to provide high-purity hydrogen during the growth process. The purifiers use palladium membrane technology to allow selective diffusion of hydrogen in a compact system with continuous monitoring of operating status.

Incorporating Johnson Matthey’s palladium membrane technology (as well as patented V-purge technology to ensure quick start-up and rapid removal of hydrogen during power failure and other alarm conditions), the PSH Series hydrogen purifiers offer a single-system solution for hydrogen flow rates of 10-60Nm3/hr. They accept inlet gases with a purity of 99.9% or better and employ a catalytic pre-purifier to protect against oxygen impurity spikes. Designed for installation in Class I, Division II environments, they are PLC-controlled with a color touch-screen HMI interface and provide continuous monitoring of purged electrical bays to ensure safety compliance.

Bestrom also says that a major US-based manufacturer of thin-film solar cells and modules (suited to large-scale utility applications, including solar farms) has installed several PSH-40 JM hydrogen purifiers at its fab in Shenzen, China for purifying hydrogen used in amorphous silicon thin-film manufacturing. “The China PV market is projected to grow 30% annually for the next several years, so JM expects to see ongoing orders for PV applications,” says Sean Peng, Asian sales manager of Gas Purification for the GPT group, which handles JM’s GPT sales, training and service throughout China.

Palladium membrane technology is preferred by PV and semiconductor fabs for use with the compressed hydrogen supply common in Asia and particularly China, says Bestrom. “Purification of compressed hydrogen is challenging because it has ppm (parts per million) levels of oxygen, hydrocarbon and nitrogen impurities that are difficult to remove using catalytic or getter purifiers,” he adds. “Customers have reported premature breakthrough and shortened lifetimes with regenerable and heated getter purifiers and this unanticipated maintenance means increased cost-of-ownership,” he explains. “Palladium purifiers remove these ppm-level impurities (O2, H2O, CO, CO2, N2 and THC) without affecting lifetime, yet still provide outlet purity less than one ppb (parts per billion).”

Another application for GPT’s hydrogen and nitrogen purifiers is in the production of silicon powder used to manufacture solar wafers. A large Europe-based renewable energy company is using multiple HP Series V-Purge hydrogen purifiers and PureGuard heated getter nitrogen purifiers to eliminate oxygen and nitrogen contamination during powder production. “The company requires ppt (parts per trillion) purity to prevent even the smallest contamination that can compromise wafer quality,” says Bestrom. “This process was developed in R&D and then transferred to a higher-volume production line,” he adds.

See related items:

JM-GPT supplies second hydrogen purifier to Taiwan’s Epileds

Super Nova Optoelectronics opts for JM-GPT PSH-30 hydrogen purifier

Johnson Matthey appoints Teratech as Korean distributor

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