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ALD-Assisted Direct Bonding

Press Release

Press Release

Physical Sciences Inc. (PSI) has been awarded a contract from the U.S. Navy to develop a method for hermetically sealing MEMS devices with matched coefficient of thermal expansion materials.

Within this program, to improve the lifetime of microelectromechanical systems (MEMS), Physical Sciences Inc. (PSI) will develop a method for hermetically sealing two silicon wafers with at least one of the wafers having a surface roughness that prevents direct bonding. While current methods exist to bond the wafers together they involve addition of materials whose coefficients of thermal expansion (CTE) are mismatched with that of silicon. Stress associated with differential expansion or contraction due a large temperature change for a long duration could lead to a plastic strain (creep). It is, therefore, inadvisable to insert materials between the silicon wafers with a material that does not have a very similar CTE to that of silicon and to insert as little as possible to achieve hermetic sealing. PSI proposes a technique that will accomplish the task of hermetic sealing and retain minimal or zero distortion due to mismatched CTEs.

For more information, contact:

Dr. Christopher Evans
Group Leader, Scalable Photonic Technologies
Physical Sciences Inc.
Office: (978) 689-0003

Acknowledgement of Sponsorship: This work is supported under a contract with the Naval Surface Warfare Center. This support does not constitute an express or implied endorsement on the part of the Government.