Method of fabricating a microfabricated high aspect ratio device with electrical isolation
AssigneeThe Regents of the University of California
InventorsTimothy J. Brosnihan, James Bustillo, William A. Clark
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Abstract
A microfabricated device having a high vertical aspect ratio and electrical isolation between a structure region and a circuit region. The device may be fabricated on a single substrate and may include electrical interconnections between the structure region and the circuit region. The device includes a substrate and an isolation trench surrounding a structure region in the substrate. The isolation trench includes a lining of a dielectric insulative material. A plurality of microstructure elements are located in the structure region and are laterally anchored to the isolation trench.
Claims19
A method of fabricating a microelectromechanical system, comprising:
- providing a substrate having a device layer including single-crystal silicon, a handle layer and a sacrificial layer between the device layer and the handle layer;
- etching a first trench in the single-crystal silicon;
- depositing a dielectric isolation layer in the first trench to form an isolation trench;
- after depositing the dielectric isolation layer, etching a second trench in the single-crystal silicon, the second trench defining a microstructure including a plurality of elements laterally anchored to the isolation trench such that the isolation trench provides electrical isolation for the anchored elements of the microstructure from each other;
- and
- removing a portion of the sacrificial layer, wherein the removed portion entirely undercuts the plurality of laterally anchored elements.
Dependencies are inferred from the claim text.