Method of manufacturing a sensor device

1 . A method of manufacturing a sensor device, the method comprising:

forming a substrate comprising a sensor element;

forming a cap layer;

bonding the cap layer to the substrate;

thinning the substrate;

forming a via between the sensor element and a back side of the thinned substrate;

providing an electrical connection between the sensor element and the back side of the thinned substrate; wherein the method further comprises:

forming a mask on the cap layer to define an area about a predetermined window region before forming of the via; and

removing a portion of the cap layer about the predetermined window region of the cap layer after formation of the via.

2 . The method according to claim 1 , wherein forming the cap layer further comprises:

disposing a getter material on at least part of an inner surface of the cap layer.

3 . The method according to claim 1 , wherein bonding the cap layer to the substrate layer comprises:

glass frit bonding the cap layer to the substrate layer.

4 . The method according to claim 3 , wherein bonding the cap layer to the substrate layer further comprises:

bonding the cap layer to the substrate layer in a pressurized atmosphere comprising a predetermined gas at a predetermined pressure.

5 . The method according to claim 1 , wherein thinning the substrate comprises:

thinning a backside of the substrate using a DRIE technique.

6 . The method according to claim 1 , further comprising:

etching the via using a DRIE technique.

7 . The method according to claim 1 , wherein removing the portion of the cap layer about the predetermined window region of the cap layer comprises:

etching the portion of the cap layer using a DRIE technique.

8 . A method of manufacturing a sensor device, the method comprising:

forming a substrate comprising a sensor element;

forming a cap layer;

bonding the cap layer to the substrate;

thinning the substrate;

forming a via between the sensor element and a back side of the thinned substrate;

providing an electrical connection between the sensor element and the back side of the thinned substrate; wherein the method further comprises:

forming a mask on the cap layer to define an area about a predetermined window region before formation of the via;

removing a portion of the cap layer about the predetermined window region of the cap layer before formation of the via; and

replacing the removed portion of the cap layer with another material to restore the cap layer to having a planar structure.

9 . The method according to claim 8 , wherein the another material is a thermally resistant polymer.

10 . The method according to claim 8 , wherein the replacement material is removed after formation of the via.

11 . The method according to claim 8 , wherein the cap layer is bonded to the substrate at a predetermined temperature, and the replacement material has a higher melting point than the predetermined temperature.

12 . A method of manufacturing a sensor device, the method comprising:

forming a substrate comprising a sensor element;

forming a cap layer;

bonding the cap layer to the substrate;

thinning the substrate;

forming a via between the sensor element and a back side of the thinned substrate;

providing an electrical connection between the sensor element and the back side of the thinned substrate; wherein formation of the cap layer comprises:

providing a first layer of silicon separated from a second layer of silicon by an oxide layer;

profiling the first layer of silicon in order provide a predetermined window region; and

removing a portion of the second layer of silicon of the cap layer about the predetermined window region to expose a portion of the oxide layer, the portion of the second layer being removed after forming the via.

13 . The method according to claim 12 , wherein bonding the cap layer to the substrate comprises:

bonding the first layer of silicon to the substrate.

14 . The method according to claim 12 , further comprising:

depositing a mask on the second layer of silicon to define the portion of the second layer of silicon to be removed.

15 . The method according to claim 14 , further comprising: etching the masked second layer of silicon until the oxide layer is reached.

16 . The method according to claim 14 , further comprising:

etching a first channel about the predetermined window region to expose a portion of the oxide layer; and

etching a second channel in the first layer of silicon, the second channel being further from a central axis of the cap layer than the first channel.

17 . The method according to claim 16 , further comprising:

etching the exposed portion of the oxide layer to release a part of the second layer of silicon that is not forming the window region.

18 . The method according to claim 12 , wherein the mask is deposited on the second layer of silicon prior to formation of the via.