Bonded wafer optical MEMS process
AssigneeAnalog Devices, Inc.
InventorsTimothy J. Brosnihhan, Michael W. Judy
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Abstract
A microelectromechanical system is fabricated from a substrate having a handle layer, a silicon sacrificial layer and a device layer. A micromechanical structure is etched in the device layer and the underlying silicon sacrificial layer is etched away to release the micromechanical structure for movement. One particular micromechanical structure described is a micromirror.
Claims42
A method of fabricating a microelectromechanical system, said method comprising:
- providing a substrate comprising a handle layer of silicon, a device layer of silicon and a sacrificial layer of silicon disposed between said handle layer and said device layer;
- forming a micromechanical structure in said device layer;
- and
- removing at least a portion of said sacrificial layer of silicon underlying said micromechanical structure to release said micromechanical structure for movement
A method of releasing a micromechanical structure for movement, said micromechanical structure etched in a silicon device layer, said method comprising:
- etching a silicon sacrificial layer disposed between said micromechanical structure and a silicon handle layer.
A microfabricated device comprising:
- a substrate having a device layer;
- a least one micro-optical device etched on said device layer and released for movement by removal of an underlying sacrificial layer of silicon;
- and
- active electronics formed on said device layer.
A microelectromechanical device comprising:
- a handle layer of silicon having actuation electrodes formed thereon;
- a device layer of silicon having a micromechanical structure formed thereon;
- and
- a sacrificial layer of silicon disposed between said handle layer and said device layer of silicon, said sacrificial layer of silicon having a portion underlying said micromechanical structure removed to form an actuation cavity below said micromechanical structure.
A micromirror device comprising:
- a substrate having a device layer, a handle layer and a sacrificial layer made of silicon disposed between said device layer and said handle layer;
- an isolation trench extending through said device layer and said sacrificial layer, said isolation trench defining a mirror region and electrically isolating said mirror region;
- a mirror formed from said device layer in said mirror region above actuation electrodes formed on said handle layer;
- and
- a cavity formed below said mirror by removing a portion of said sacrificial layer of silicon.
Dependencies are inferred from the claim text.