Lead Inventor: Xi Chen, Ph.D.

Problem or Unmet Need:
While much of the focus and attention is garnered by microelectronics, micromechanical devices, most notably MEMS, are more ubiquitous than many realize. Micromechanical devices enable motion sensitive feedback in our handheld devices, and trigger the airbags present in nearly all automobiles now. The fabrication of such devices is complex and involved, requiring multilayered materials and many processing steps. The ability to induce mechanical self-assembly of desired shapes and structures would greatly simplify the fabrication of these devices.

Details of the Invention:
The technology uses controlled buckling of thin films on curved substrates to give rise to structure to higher-archical structure. Both positive and negative curvature substrates are used to achieve quasi 2-D and 3-D gear-like micro-components. The number, width, and depth of teeth can be controlled through the geometry and properties of the film and substrate. A model has been established that predicts morphology of based on these parameters allowing for precise control of components. A variety of gears have been realized through this technology including bevel and helical gears, which are particularly difficult to fabricate using conventional lithographic techniques.

Applications:
• Micro-gears for use in microelectromechanical systems (MEMs) devices
• Mechanical components for use in implantable or other medical devices where bio-compatibility is required
• Fabrication of tunable optical gratings

Advantages:
• Low cost, fast method for fabrication of 3-D microstructures, increasing overall efficiency
• Gears are polymer based and can be designed to be bio-compatible/inert
• Geometry is controllable through simple parameter variations
• Eliminates complex lithographic processes for micromachining such components and enables conformations not previously achievable

Patent Status: Patent Pending

Licensing Status: Available for Licensing and Sponsored Research Support

Publications: Mechanical Self-Assembly Fabrication of Gears.
Jie Yin, Eyal Bar-Kochba, and Xi Chen, Soft Matter, 2009, 5: 3469-3474.

Further Information
Paul van der Wilt
Email: TechTransfer@columbia.edu

File Number: M10-011