New patent for Metal Lift-Off Processing - FluidJet

ALBANY, Ore.—September 23, 2015—

MEI Wet Processing Systems and Services announced today their receipt of a patent from the US Patent Office for one of their targeted semiconductor processing applications. This patent protects MEI’s unique metal lift-off process which was trademarked earlier under the name FluidJet™
The U.S. Patent No. 9,070,631 describes a new approach to providing metal liftoff by defining the specific designs and methods used to produce a gentle, low cost, small footprint system for semiconductor processing.

“This latest patent contains more than twenty claims protecting the unique methods by which we significantly improve the efficiency and effectiveness of our metal removal process in batch immersion systems”, said Semiconductor Applications Engineering Director Scott Tice. “These granted claims further establish MEI’s leadership position in batch immersion systems for semiconductor device manufacturing.”

The patent covers the technology and methods behind MEI’s FluidJet™ batch wet processing system. This capability enables gentle metal liftoff for sensitive MEMS and compound semiconductor devices which may
be damaged by single wafer high-pressure systems. Through the patented design, the systems hydraulics, agitation, and ultrasonics are harnessed by MEI”s proprietary IDX software controls to provide superior metal liftoff, resist strip and sidewall polymer cleans. MEI’s gentle liftoff solution delivers higher yield, more cost-effective semiconductor wafer processing by providing higher throughput per square foot with significantly reduced chemical consumption over earlier single wafer system designs.
MEI’s FluidJet™ batch wet processing provides clean, gentle, efficient metal removal with no metal re-deposition on either the front or back of the wafer. This eliminates downstream focal errors which impact yield and production flow. In addition, FluidJet™ design provides simplified Gold and other precious metal reclaim, reducing reclaim cycle time and system PM maintenance. The FluidJet™ design also saves valuable manufacturing floor space by reducing the wet process footprint requirement substantially with comparable throughput to earlier single wafer spray tool designs.
This “additive” or “liftoff” approach to device manufacturing continues to grow due to its advantages for unique geometries required in today’s semiconductor devices. In the metal liftoff approach, resist is first patterned on the substrate surface followed by subsequent deposition of metal by sputter deposition or evaporation methods. The sacrificial resist layer is then dissolved in a suitable solvent, lifting off the metal on top of the resist while leaving metal on the open areas of the substrate. The “liftoff” technique allows for the creation of metal patterns comprising different metal layers in contrast to the alternative approach of selective removal in an “etch-back” system.

“By adopting the FluidJet™ metal liftoff system, semiconductor manufacturers will increase yield while reducing downtime, chemical costs, and disposal,” said Dan Cappello, President, and CEO, MEI LLC.

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About MEI Wet Processing Systems and Services:

MEI Wet Processing Systems and Services LLC of Albany, Oregon, is a wet processing equipment and services company serving the semiconductor, MEMs, solar, and high technology industries. MEI Wet Processing has sales offices in the United States, Europe, China, and Taiwan. MEI’s specialties include patented solutions for wet processing applications, automated and semi-automated wet benches, process systems and services; automated chemical delivery systems; and IDX Flexware process control automation software. MEI has a commitment to outstanding customer service. www.rena-na.com.