Hermetically sealed MEMS mirror and method of manufacture

1. A micro-electro mechanical system (MEMS) device, comprising:

a substrate;

a MEMS mirror stack on the substrate and having a width greater than a width of the substrate in at least one direction;

a first bonding layer sealing against ingress of environmental contaminants and mechanically anchoring the MEMS mirror stack to the substrate;

an interconnection layer stacked on the first bonding layer and in contact with the MEMS mirror stack;

a support layer stacked on the first bonding layer;

a transparent cap layer on the MEMS mirror stack;

a second bonding boding layer sealing against ingress of environmental contaminants and mechanically anchoring the transparent cap layer to the MEMS mirror stack;

at least one pad extending away from the MEMS mirror stack opposite the transparent cap layer and left exposed by the MEMS mirror stack having a width greater than the width of the substrate in the at least one direction; and

a metal layer running from the MEMS mirror stack, through the interconnection layer, through the support layer, and to the at least one pad.

2. The MEMS device of claim 1 , wherein the MEMS mirror stack comprises:

a stator mechanically joined to the interconnection layer; and

a rotor associated with the stator and configured to rotate with respect thereto.

3. The MEMS device of claim 2 , wherein the substrate has a first recess formed therein; wherein the transparent cap layer has a second recess formed therein; and wherein the first and second recesses form upper and lower chambers through which at least a portion of the rotor rotates when rotating with respect to the stator.

4. The MEMS device of claim 3 , wherein air pressure within the upper and lower chambers is within a threshold of vacuum.

5. The MEMS device of claim 2 , wherein the stator and rotor are collocated such that the rotor rotates in a plane occupied by the stator.

6. The MEMS device of claim 2 , wherein the rotor rotates in a plane not occupied by the stator.

7. The MEMS device of claim 1 , wherein the transparent cap layer comprises glass.

8. The MEMS device of claim 1 , wherein the transparent cap layer has a width less than a width of the MEMS mirror stack in at least one direction.

9. A micro-electro mechanical system (MEMS) device, comprising:

a substrate having a first recess defined therein;

a first bonding layer disposed on the substrate;

a support layer stacked on the first bonding layer;

a MEMS mirror stack disposed on the first bonding layer and having a width greater than a width of the substrate in at least one direction;

an interconnection layer stacked on the first bonding layer and in contact with the MEMS mirror stack;

a second bonding layer disposed on the MEMS mirror stack; and

a transparent cap layer disposed on the second bonding layer and having a second recess defined therein;

wherein the MEMS mirror stack includes a rotor that rotates to travel through the first and second recesses;

wherein the first and second bonding layers environmentally seal against environmental egress into the first and second recesses;

at least one pad extending away from the MEMS mirror stack opposite the transparent cap layer and left exposed by the MEMS mirror stack having a width greater than the width of the substrate in the at least one direction; and

a metal layer running from the MEMS mirror stack, through the interconnection layer, through the support layer, and to the at least one pad.

10. The MEMS device of claim 9 , wherein the MEMS mirror stack comprises:

a stator disposed on and bonded to the interconnection layer;

a rotor layer disposed on the interconnection layer; and

a mirror disposed on the rotor layer;

wherein the second bonding layer is disposed on non-rotating portions of the rotor layer.

11. The MEMS device of claim 9 , wherein the MEMS mirror stack comprises:

a rotor-stator layer disposed on the interconnection layer, the rotor-stator layer containing collocated rotor and stator elements; and

a mirror disposed on the rotor element of the rotor-stator layer;

wherein the second bonding layer is disposed on non-rotating portions of the rotor-stator layer.