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US 5,493,470 AGranted
SOI diaphragm sensor
AssigneeKopin Corporation
InventorsPaul M. Zavracky, Richard H. Morrison, Jr.
Life of this patent
Estimating the term…
Abstract
The present invention relates to the fabrication of diaphragm pressure sensors utilizing silicon-on-insulator technology where recrystallized silicon forms a diaphragm which incorporates electronic devices used in monitoring pressure. The diaphragm is alternatively comprised of a silicon nitride having the necessary mechanical properties with a recrystallized silicon layer positioned thereon to provide sensor electronics.
Claims20
A method of making a pressure sensor comprising:
- providing a supporting substrate;
- forming an insulating layer on the substrate;
- forming a layer of single crystal silicon over the insulating layer;
- forming a monitoring circuit formed in or on the silicon layer;
- forming a diaphragm positioned in or on the layer of single crystal silicon;
- forming insulator clamps extending through the silicon layer and the insulator layer along a peripheral portion of the diaphragm, each clamp being attached to the diaphragm for supporting the diaphragm over a cavity to be formed in the insulator, each clamp being formed of an electrical insulator for electrically isolating the diaphragm from the substrate;
- and
- removing a portion of the insulating layer under the diaphragm to form the cavity such that the diaphragm can be displaced and thereby alter an electrical characteristic of the circuit.
5 more elements
A method of making a pressure sensor comprising:
- providing a semiconductor substrate;
- forming a layer of insulating material on the substrate;
- forming a layer of single crystal or essentially single crystal silicon material formed over the insulating layer;
- forming a circuit positioned in or on the single crystal or essentially single crystal material;
- forming a diaphragm in the silicon layer;
- forming channels through the layer of silicon material adjacent a peripheral portion of the diaphragm and into the insulating layer;
- forming a clamp in each channel, each clamp being attached to the diaphragm for supporting the diaphragm over a cavity to be formed, the clamps being formed of an electrical insulating material for electrically isolating the diaphragm from the substrate;
- and
- removing a portion of the insulating layer to form the cavity, such that displacement of the diaphragm alters an electrical characteristic of the circuit.
6 more elements
A method of making a pressure sensor comprising:
- providing a semiconductor substrate;
- forming a layer of insulating material on the substrate;
- forming a layer of single crystal silicon formed over the insulating layer;
- forming a circuit positioned in or on the single crystal silicon;
- forming a diaphragm in the silicon layer;
- forming channels through the layer of silicon material adjacent a peripheral portion of the diaphragm and into the insulating layer;
- forming a sacrificial region in contact with a portion of the insulating layer to be removed from underneath the diaphragm;
- forming a clamp attached to the diaphragm for supporting the diaphragm over the insulating layer portion to be removed to form a cavity, the clamps being formed of an electrical insulating material for electrically isolating the diaphragm from the substrate;
- and
- removing the sacrificial region and the portion of the insulating layer to form the cavity, such that displacement of the diaphragm alters an electrical characteristic of the circuit.
7 more elements
Dependencies are inferred from the claim text.