Piezoelectric optical MEMS device with embedded moisture layers
A piezoelectric optical micro-electro-mechanical systems (POMEMS) device includes a glass layer having a bottom surface and a top surface. The device may also include an upper moisture barrier layer having a top surface and a bottom surface in which the bottom surface of the top moisture barrier layer is substantially coextensive with and interfaces with the top surface of the glass layer. A piezo stack may be attached above the upper moisture barrier layer. The device may also include a lower moisture barrier layer having a bottom surface and a top surface. The top surface of the lower moisture barrier layer is substantially coextensive with and interfaces with the bottom surface of the glass layer. A semiconductor substrate may be attached below the bottom moisture barrier layer.
1. A piezoelectric optical micro-electro-mechanical systems (POMEMS) device comprising:
a glass layer having a first surface and an opposite second surface;
a first moisture barrier layer having a first surface and an opposite second surface, said second surface of said first moisture barrier layer being substantially coextensive with and interfacing with said first surface of said glass layer; at least a piezo stack being attached on said first side of said first moisture barrier layer; and
a second moisture barrier layer having a first surface and an opposite second surface, said first surface thereof being substantially coextensive with and interfacing with said second surface of said glass layer; at least a semiconductor substrate being attached on said second side of said second moisture barrier layer.
2. The POMEMS device of claim 1 wherein at least one of said first and second moisture barrier layers comprises at least a single film layer.
3. The POMEMS device of claim 2 wherein at least one of said first and second moisture barrier layers comprises a plurality of film layers.
4. The POMEMS device of claim 2 wherein at least one of said first and second moisture barrier layers comprises at least one film layer of oxide.
5. The POMEMS device of claim 2 wherein at least one of said first and second moisture barrier layers comprises a film layer of SiON.
6. The POMEMS device of claim 2 wherein at least one of said first and second moisture barrier layers comprises a film layer of SiN.
7. The POMEMS device of claim 2 wherein at least one of said first and second moisture barrier layers comprises an etch stop layer.
8. The POMEMS device of claim 7 wherein said etch stop layer is plasma etched and said glass layer is not plasma etched.
9. The POMEMS device of claim 2 wherein said piezo stack is not coextensive with said first moisture barrier and a portion of said first moisture barrier is exposed.
10. The POMEMS device of claim 2 wherein said semiconductor substrate is not coextensive with said second moisture barrier and a portion of said second moisture barrier is exposed.