Photon counting radiation detector and radiographic inspection device using the same
A photon counting radiation detector includes a cell structure including a substrate and an epitaxial layer provided on the substrate, radiation being incident on the epitaxial layer; an inclination θ of the substrate being set in a predetermined range, where t sub is a thickness of the substrate, t epi is a thickness of the epitaxial layer, L is a length of the substrate, and the inclination θ is an inclination of the substrate with respect to an incident direction of the radiation. The epitaxial layer is preferably one type selected from SiC, Ga 2 O 3 , GaAs, GaN, diamond, and CdTe. Such a photon counting radiation detector is preferably a direct converting type.
1. A photon counting radiation detector, comprising:
a cell structure including
a substrate, and
an epitaxial layer provided on the substrate, radiation being incident on the epitaxial layer;
an inclination θ of the substrate satisfying Formula (1) below, where t sub is a thickness of the substrate, t epi is a thickness of the epitaxial layer, L is a length of the substrate, and the inclination θ is an inclination of the substrate with respect to an incident direction of the radiation and is greater than 0°:
θ
≦
tan
θ
≦
L
±
L
2
-
4
t
sub
(
t
sub
+
t
epi
)
2
(
t
sub
+
t
epi
)
.
(
1
)
2. The photon counting radiation detector according to claim 1 , wherein
the thickness of the substrate is 500 μm or less.
3. The photon counting radiation detector according to claim 1 , wherein
the thickness of the epitaxial layer is 100 μm or less.
4. The photon counting radiation detector according to claim 1 , wherein the epitaxial layer includes one type selected from SiC, Ga 2 O 3 , GaAs, GaN, diamond, and CdTe.
5. The photon counting radiation detector according to claim 1 , wherein
the cell structure further includes an electrode.
6. The photon counting radiation detector according to claim 5 , wherein
the electrode provided in the cell structure includes one or more types selected from the group consisting of carbon, silicon, titanium, platinum, and nickel.
7. The photon counting radiation detector according to claim 1 , further comprising
an array structure including a plurality of the cell structures and a plurality of insulating spacers provided between adjacent pairs of the plurality of cell structures, the plurality of cell structures and the plurality of insulating spacers being alternately arranged side by side in a lateral direction.
8. The photon counting radiation detector according to claim 7 , further comprising
a plurality of the array structures stacked in the incident direction of the radiation.
9. The photon counting radiation detector according to claim 1 , wherein the photon counting radiation detector is a direct converting type.
10. A radiographic inspection device, comprising:
the photon counting radiation detector according to claim 1 .
11. The photon counting radiation detector according to claim 1 , wherein
the thickness of the substrate is 500 μm or less, and
the thickness of the epitaxial layer is 100 μm or less.
12. The photon counting radiation detector according to claim 11 , wherein
the cell structure further includes an electrode.
13. The photon counting radiation detector according to claim 12 , wherein
the electrode provided in the cell structure includes one or more types selected from the group consisting of carbon, silicon, titanium, platinum, and nickel.