Imaging device, imaging module and method for manufacturing imaging device
According to one embodiment, an imaging device includes a substrate, a photodetecting portion, a circuit portion and a through interconnect. The substrate has a first major surface, a second major surface on a side opposite to the first major surface, a recess portion provided on the first major surface and retreated in a first direction going from the first major surface to the second major surface, and a through hole communicating with the first major surface and the second major surface and extending in the first direction. The photodetecting portion is provided above the recess portion and away from the substrate. The circuit portion is electrically connected to the photodetecting portion and provided on the first major surface. The through interconnect is electrically connected to the circuit portion and provided inside the through hole. The recess portion has a first inclined surface. The through hole has a second inclined surface.
1. An imaging device comprising:
a substrate having a first major surface, a second major surface on a side opposite to the first major surface, a recess portion provided on the first major surface and retreated in a first direction going from the first major surface to the second major surface, and a through hole communicating with the first major surface and the second major surface and extending in the first direction;
a photodetecting portion provided above the recess portion and away from the substrate;
a circuit portion electrically connected to the photodetecting portion and provided on the first major surface; and
a through interconnect electrically connected to the circuit portion and provided inside the through hole,
the recess portion having a first inclined surface inclined to the first major surface, and
the through hole having a second inclined surface in parallel with the first inclined surface.
2. The device according to claim 1 , wherein
the second inclined surface includes a surface exposed by anisotropic etching of the substrate.
3. The device according to claim 1 , wherein
the substrate contains silicon,
the first major surface is a {100} surface of the silicon, and
the second inclined surface includes a {111} surface of the silicon.
4. The device according to claim 3 , wherein
the second inclined surface includes a surface of an angle of 55° to the first major surface.
5. The device according to claim 1 , wherein
a maximum opening size of the through hole is larger than a maximum opening size of the recess portion.
6. The device according to claim 1 , further comprising:
a lid provided above a side opposite to the substrate of the photodetecting portion and away from the photodetecting portion,
a sealed first space portion being provided between the recess portion of the substrate and the photodetecting portion, and
a sealed second space portion being provided between the lid and the photodetecting portion.
7. The device according to claim 6 , wherein
a pressure inside the first space portion is lower than the atmospheric pressure, and
a pressure inside the second space portion is lower than the atmospheric pressure.
8. The device according to claim 6 , wherein
a projecting portion thicker than a thickness of the photodetecting portion along the first direction is provided around the photodetecting portion, and
the lid is provided on the projecting portion.
9. The device according to claim 8 , wherein
a support leg supporting the photodetecting portion is provided between the photodetecting portion and the projecting portion.
10. The device according to claim 1 , wherein
a width of the opening of the recess portion in a direction along the first major surface gets smaller from the first major surface toward the second major surface on the side opposite to the first major surface of the substrate, and
a width of the opening of the through hole in a direction along the second major surface gets smaller from the second major surface toward the first major surface.
11. The device according to claim 1 , further comprising:
a bump electrode provided on the second major surface, projecting along the first direction, and electrically connected to the through interconnect.
12. The device according to claim 1 , wherein
the photodetecting portion is provided in a plurality along the first major surface.
13. The device according to claim 10 , wherein
the photodetecting portion is arranged in a plurality in a matrix state along the first major surface.
14. An imaging module comprising:
an imaging device; and
a lens,
the imaging device including:
a substrate having a first major surface, a second major surface on a side opposite to the first major surface, a recess portion provided on the first major surface and retreated in a first direction going from the first major surface to the second major surface, and a through hole communicating with the first major surface and the second major surface and extending in the first direction;
a photodetecting portion provided above the recess portion and away from the substrate;
a circuit portion electrically connected to the photodetecting portion and provided on the first major surface;
a through interconnect electrically connected to the circuit portion and provided inside the through hole; and
a lid provided above a side opposite to the substrate of the photodetecting portion and away from the photodetecting portion,
the recess portion having a first inclined surface inclined to the first major surface, and
the through hole having a second inclined surface in parallel with the first inclined surface, and
the lens provided on the lid of the imaging device.
15. The module according to claim 14 , wherein
the photodetecting portion is provided in a plurality along the first major surface.
16. The module according to claim 14 , wherein
the photodetecting portion is arranged in a plurality in a matrix state along the first major surface.