Image sensing device with cap and related methods
An image sensing device includes an interconnect layer and a number of grid array contacts arranged on a bottom side of the interconnect layer. An image sensor integrated circuit (IC) is carried by the interconnect layer and has an image sensing surface. A number of electrical connections are coupled between the image sensor IC and an upper side of the interconnect layer. A transparent plate overlies the image sensing surface of the image sensor IC. A cap is carried by the interconnect layer and has an opening overlying transparent plate and the image sensing surface. The cap has an upper wall spaced above the interconnect layer and the image sensor IC to define an internal cavity and the cap defines an air vent coupled to the internal cavity.
1. An image sensing device comprising:
an interconnect layer and a plurality of ball grid array (BGA) contacts carried thereby;
an image sensor integrated circuit (IC) carried by the interconnect layer and coupled to the plurality of BGA contacts by vias extending through the interconnect layer, the image sensor IC having an image sensing surface;
a transparent plate carried by the image sensor IC and overlying the image sensing surface; and
a cap carried by the interconnect layer and having an opening overlying the image sensing surface, the cap having an upper surface that is offset relative to an upper surface of the transparent plate, wherein the cap has an upper wall spaced above the interconnect layer and the image sensor IC to define an internal cavity and wherein the cap defines an air vent that extends along the upper wall of the cap and couples the opening with the internal cavity.
2. The image sensing device of claim 1 , further comprising a plurality of bond wires extending between the image sensor IC and the interconnect layer.
3. The image sensing device of claim 2 , further comprising encapsulation material covering a portion of the plurality of bond wires.
4. The image sensing device of claim 1 , wherein the transparent plate is received within the opening of the cap.
5. The image sensing device of claim 1 , further comprising adhesive material between the cap and the transparent plate.
6. The image sensing device of claim 1 , further comprising adhesive material between the transparent plate and the image sensor IC.
7. The image sensing device of claim 1 , wherein the air vent extends vertically through the upper wall of the cap.
8. The image sensing device of claim 1 , further comprising a surface mounted component overlying the interconnect layer and laterally spaced from the image sensor IC.
9. The image sensing device of claim 8 , wherein the surface mounted component comprises a resistor or a capacitor.
10. A method of making an image sensing device, the method comprising:
attaching an image sensor integrated circuit (IC) to an upper surface of an interconnect layer, a plurality of ball grid array contacts being carried on a lower surface of the interconnect layer, wherein the upper surface is opposite the lower surface;
electrically connecting the image sensor IC to the interconnect layer;
coupling a transparent plate to the image sensor IC so that the transparent plate overlies an image sensing surface of the image sensor IC; and
coupling a cap to the interconnect layer so as to form an internal cavity between the image sensor IC and an upper wall of the cap, the upper wall having an opening exposing the transparent plate, wherein the cap defines an air vent coupled between the internal cavity and an external atmospheric environment through the opening so that the internal cavity is freely and fluidly coupled to the external atmospheric environment.
11. The method of claim 10 , wherein coupling the cap to the interconnect layer comprises coupling the cap so that an inner peripheral edge of the cap is spaced from adjacent portions of the transparent plate to define the air vent.
12. The method of claim 10 , wherein the air vent extends vertically through the upper wall of the cap.
13. The method of claim 10 , wherein electrically connecting the image sensor IC to the interconnect layer comprises a wire bonding operation.
14. The method of claim 10 , further comprising attaching the ball grid array contacts to the interconnect layer.
15. A method of making an image sensing device, the method comprising:
attaching an image sensor integrated circuit (IC) to an upper surface of an interconnect layer, a plurality of grid array contacts being carried on a lower surface of the interconnect layer, wherein the upper surface is opposite the lower surface;
electrically connecting the image sensor IC to the interconnect layer;
coupling a transparent plate to the image sensor IC so that the transparent plate overlies an image sensing surface of the image sensor IC; and
coupling a cap to the interconnect layer so as to form an internal cavity between the image sensor IC and an upper wall of the cap, the upper wall having an opening exposing the transparent plate, wherein the cap couples the internal cavity to the external atmospheric environment via an air vent in the upper wall of the cap and the opening.
16. The method of claim 15 , wherein electrically connecting the image sensor IC to the interconnect layer comprises a wire bonding operation.
17. The method of claim 15 , further comprising attaching the grid array contacts to the interconnect layer.
18. The method of claim 15 , wherein the grid array contacts comprise ball grid array contacts.
19. The method of claim 15 , wherein a top surface of the transparent plate is flush with an upper surface of the cap.
20. The method of claim 15 , wherein a top surface of the transparent plate is offset relative to an upper surface of the cap.