High-resolution in-plane tuning fork gyroscope and methods of fabrication
First Claim
1. A gyroscope comprising:
- an electrically-conductive substrate comprising a lower support layer and an upper flexible support layer;
first and second separated proof masses lying in and supported by the upper flexible support layer that are separated from the lower support layer;
first and second drive electrodes disposed adjacent to the proof masses that are insulatably supported by the lower support layer and that are separated from the upper flexible support layer;
sense electrodes disposed adjacent to the proof masses that are insulatably supported by the lower support layer and that are separated from the upper flexible support layer; and
tuning electrodes disposed adjacent to the proof masses that are insulatably supported by the lower support layer and that are separated from the upper flexible support layer.
1 Assignment
0 Petitions
Accused Products
Abstract
A microstructure comprising an in-plane solid-mass electrically conductive tuning fork gyroscope and fabrication methods. The gyroscope is formed using substrate material having lower and upper layers sandwiching a sacrificial insulating layer. An exemplary gyroscope comprises a low-resistivity single-crystal silicon substrate having a lower support layer and an upper flexible support layer. Two opposed proof masses that are separated from the lower support layer lie in and are supported by the upper flexible support layer. Two drive electrodes are disposed adjacent to the proof masses and are insulatably supported by the lower support layer and are separated from the upper flexible support layer. Sense, balance and tuning electrodes are disposed adjacent to the proof masses and are insulatably supported by the lower support layer and are separated from the upper flexible support layer. The operational mode shapes are in-plane with the substrate surface and only measures angular motion that are orthogonal to the plane of the substrate. The microstructure flexural design enables the sense and the drive resonant frequencies to occur in close proximity of one another. This enables matched-mode operation of the device thereby ensuring maximum sensitivity.
-
Citations
12 Claims
-
1. A gyroscope comprising:
-
an electrically-conductive substrate comprising a lower support layer and an upper flexible support layer;
first and second separated proof masses lying in and supported by the upper flexible support layer that are separated from the lower support layer;
first and second drive electrodes disposed adjacent to the proof masses that are insulatably supported by the lower support layer and that are separated from the upper flexible support layer;
sense electrodes disposed adjacent to the proof masses that are insulatably supported by the lower support layer and that are separated from the upper flexible support layer; and
tuning electrodes disposed adjacent to the proof masses that are insulatably supported by the lower support layer and that are separated from the upper flexible support layer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A gyroscope comprising:
-
an electrically-conductive substrate comprising a lower support layer and an upper flexible support layer;
first and second separated proof masses lying in and supported by the upper flexible support layer that are separated from the lower support layer;
first and second drive electrodes disposed adjacent to the proof masses that are insulatably supported by the lower support layer and that are separated from the upper flexible support layer;
sense electrodes disposed adjacent to the proof masses that are insulatably supported by the lower support layer and that are separated from the upper flexible support layer; and
tuning electrodes disposed adjacent to the proof masses that are insulatably supported by the lower support layer and that are separated from the upper flexible support layer;
wherein drive and sense operational modes occur in a plane defined by the upper layer, and wherein resonant frequencies of in-plane operational modes of the gyroscope are in close proximity to one another to provide for matched mode operation.
-
-
10. A method of forming a gyroscope, comprising:
-
providing an electrically-conductive substrate comprising lower and upper layers having a sacrificial insulating layer disposed therebetween; and
patterning and etching the substrate to define first and second separated proof masses formed in the upper layer that are suspended above the lower layer, first and second drive electrodes formed in the upper layer and disposed adjacent to the proof masses that are supported by the insulating layer and lower layer and that have portions thereof adjacent to the proof masses that are suspended above the lower layer, sense electrodes formed in the upper layer disposed adjacent to the proof masses that are supported by the insulating layer and lower layer, and tuning electrodes formed in the upper layer disposed adjacent to the proof masses that are supported by the insulating layer and lower layer. - View Dependent Claims (11, 12)
-
Specification