Lab, Industry Team Up To Create Enhanced Optical Network Elements

The critical first step of creating miniature molds for micro-structure components takes place in a beamline at the ALS, one of the world's leading producers of soft X-rays. The beamline was built for use by AXSUN Technologies, of Billerica, Mass., and was dedicated today by the laboratory and AXSUN officials. It marks the first time that a private company has paid for an entire ALS beamline.

"It’s a win-win for both parties, and illustrates the great value of public-private partnerships," said Charles Shank, Director of Berkeley Lab. "The output of this beamline will help address one of our nation’s biggest telecommunications challenges, and at the same time, AXSUN’s support will increase our capacity to deliver on other scientific missions."

Dale Flanders, President and CEO of AXSUN, said, "AXSUN has been working with the Berkeley Lab since before the company’s founding in 1999, and we are pleased to be extending our partnership to include the operation of an AXSUN beamline. We believe that the relationship between the Berkeley Lab and AXSUN will serve as a model for future commercialization of dual use technology."

AXSUN, which has been in operations since 1999 and opened a West Coast manufacturing branch in Livermore this year, is a developer and manufacturer of photonic subsystems for optical networking. Their products address a major obstacle in optimizing the performance of fiber-optic networks that power the Internet: specifically to offer complex, integrated subsystems that occupy smaller footprints than today’s bulkier, discrete versions.

AXSUN’s products, such as its optical performance monitor, are designed to manage optical networks through the integration of advanced MEMS devices with a wide range of supporting optical functions. AXSUN’s subsystem products are one-tenth the size of those built by hand, using bulk optics methods. The result is higher levels of performance and functional density while consuming less power and circuit board space.

Key to this process is the production of micro-alignment structures used to mount optical elements such as the lenses to the optical equivalent of a circuit board. That’s where the Advanced Light Source beamline comes in.

The ALS has proven to be the ideal vehicle for enabling a process called LIGA, a technology developed in Germany that uses X-ray lithography instead of conventional metal machining to create tiny metal structures with sub-micron precision. The ALS X-rays are exposed to an acrylic sheet, which is bonded to a silicon wafer containing a mask of the LIGA structures. After the X-rays hit the mask, the acrylic is etched in a manner that creates precise molds of micro-alignment structures. Dale Boehme, Director of LIGA Technology for AXSUN, said, "The ALS is a great synchrotron source for performing LIGA X-ray exposures because it provides maximum power radiated at energies ideal for exposing these molds."

The exposed acrylic wafers will be sent to AXSUN’s Livermore foundry, where they will be chemically processed, electroplated, lapped and polished, and released from the substrate. This wafer scale process creates thousands of alignment structures on a single 3-inch wafer. The structures are then assembled into the photonic platforms.

The 14,000-square-foot office and manufacturing facility at 7693 Longard Road in East Livermore opened in March, and will serve as AXSUN’s West Coast headquarters and LIGA fabrication hub. AXSUN executed a licensing agreement last year for certain LIGA process technology with Sandia National Laboratory, another DOE facility in Livermore, and is continuing to work with Sandia as a research and development partner.

Berkeley Lab’s Advanced Light Source is a national user facility that generates intense light for scientific and technological research. As the world’s brightest source of ultraviolet and soft X-ray beams -- and the world’s premiere third-generation synchrotron light source in its energy range -- the ALS welcomes researchers from universities, industries, and government laboratories around the world. The U.S Department of Energy’s Office of Basic Energy Sciences funds it.

Contributing to the construction of the AXSUN beamline at Berkeley Lab, under the technical direction of Howard Padmore and project management of Jim Krupnick, were William Thur and Sergio Gavidia. Padmore said, "The path to an industrial LIGA facility at ALS started in 1994 with the programs on two existing time-shared beamlines. The use of LIGA for a dedicated industrial production facility is something that the ALS management strongly backed over the years. It is particularly satisfying to see this project come to fruition working with Dale Boehme at AXSUN, who was responsible for much of this early development work."

Berkeley Lab is an unclassified scientific research laboratory managed by the University of California for the Department of Energy.