Sapphire is an ideal material for windows used in extreme environments, but producing large-form windows is difficult

Rubicon draws on its expertise to develop a unique new crystal growth platform

Rubicon Technology, Inc. (NASDAQ:RBCN), a leading provider of sapphire substrates and products to the LED, semiconductor, and optical industries, announced a ground-breaking project, dubbed Large-Area Net-shape Crystal Extraction (LANCE), developed to produce large-area sapphire windows of optical quality for military sensing applications. The project is supported by a grant from the Air Force Research Laboratory (AFRL), with a total value of $4.7 million over three years.

Existing methods used to produce sapphire windows do not meet all the demands of military applications. Rubicon Technology has developed an entirely new growth platform specifically to produce very large polished sapphire infrared (IR) windows for the Air Force Research Laboratory. Production will be scaled to meet the current and future requirements of the Air Force, beginning with intermediate sizes and progressing to windows as large as 36 x 18 x 0.8 inches. These sapphire windows will meet a variety of needs in both government and private sector applications.

Sapphire is a desirable material for military and other high-performance applications due to its hardness and strength, transparency in the visible and IR spectrum, thermal conductivity, thermal shock resistance, abrasion resistance, high melting point and chemical inertness. As a result, it is ideally suited for IR windows in extreme environments where material durability is just as important as optical clarity.
 
“Sapphire’s exceptional physical and optical qualities offer many benefits in applications such as military IR windows,” noted Raja M. Parvez, President and CEO of Rubicon Technology. “However, producing high-quality sapphire large enough for such applications has proven difficult. So Rubicon drew on more than a decade of experience and our culture of innovation in crystal growth technology to develop an entirely new platform to address this need. This research sets the stage for many defense and industrial applications for large sapphire windows of exceptional optical quality.

“We are honored to be working with the Air Force Research Laboratory to create this new technology, and look forward to helping customers in other industries realize the benefits of large-area optical sapphire windows.”

Existing growth technologies that produce large-area sapphire crystals are incapable of generating the thickness required for demanding defense applications. Rubicon’s new technological platform will grow panels approximately two inches thick, which can be cut into multiple windows of varying thickness to meet the needs of the industry. The platform developed through the LANCE project is distinct from Rubicon’s highly regarded ES2 crystal growth technology, which will remain the platform for Rubicon’s C-plane sapphire used in the LED industry and R-plane sapphire for Silicon-on-Sapphire RFIC applications.