Radiation image-pickup device and radiation image-pickup display system
View Patent ↗A radiation image-pickup device includes: a plurality of pixels configured to generate signal charge based on radiation; and a field effect transistor used to read out the signal charge from the plurality of pixels. The transistor includes a first silicon oxide film, a semiconductor layer, and a second silicon oxide film laminated in order from a substrate side, the semiconductor layer including an active layer, and a first gate electrode disposed to face the semiconductor layer, with the first or the second silicon oxide film interposed therebetween, and the first or the second silicon oxide film or both include an impurity element.
1. A radiation image-pickup device comprising:
a plurality of pixels configured to generate signal charge based on radiation; and
at least two transistors per pixel used to read out the signal charge from the plurality of pixels,
wherein the at least two transistors are connected to each other in series,
wherein the at least two transistors each comprise:
a first nitride film adjacent to a substrate side, a first silicon oxide film, a semiconductor layer, and a second silicon oxide film laminated in order from the substrate side; and
a first gate electrode disposed such that the first or the second silicon oxide film is interposed between the first gate electrode and the semiconductor layer,
wherein the semiconductor layer comprises an active layer, and
wherein the first or the second silicon oxide film or both include an impurity element comprising at least one of antimony or bismuth.
2. The radiation image-pickup device according to claim 1 , wherein
the at least two transistors each comprise the first gate electrode, the first silicon oxide film, the semiconductor layer, and the second silicon oxide film in order from the substrate side, and
the at least two transistors each further comprise a second gate electrode on the second silicon oxide film, disposed on a side of the semiconductor layer opposite to the first gate electrode.
3. The radiation image-pickup device according to claim 2 , wherein
the first and the second silicon oxide films are disposed to be adjacent to the semiconductor layer, and
the first and the second silicon oxide films both include the impurity element.
4. The radiation image-pickup device according to claim 2 , wherein, of the first and the second silicon oxide films, only the second silicon oxide film includes the impurity element.
5. The radiation image-pickup device according to claim 2 , wherein, of the first and the second silicon oxide films, only the first silicon oxide film includes the impurity element.
6. The radiation image-pickup device according to claim 1 , wherein the impurity element is provided in a selective region disposed opposite a channel part of the semiconductor layer, by doping.
7. The radiation image-pickup device according to claim 1 , further comprising a pixel section comprising the plurality of pixels and a peripheral circuit section peripheral to the pixel section, wherein, of the pixel section and the peripheral circuit section, only the pixel section is doped with the impurity element.
8. The radiation image-pickup device according to claim 1 , wherein the impurity element further includes fluorine (F).
9. The radiation image-pickup device according to claim 1 , wherein a dosage of the impurity element is about 1.0×10 11 atoms per square centimeter or more, and about 1.0×10 13 atoms per square centimeter or less.
10. The radiation image-pickup device according to claim 1 , wherein the at least two transistors each comprise the first silicon oxide film, the semiconductor layer, the second silicon oxide film, and the first gate electrode in order from the substrate side.
11. The radiation image-pickup device according to claim 10 , wherein, of the first and the second silicon oxide films, at least the second silicon oxide film includes the impurity element.
12. The radiation image-pickup device according to claim 1 , wherein the at least two transistors each comprise the first gate electrode, the first silicon oxide film, the semiconductor layer, and the second silicon oxide film in order from the substrate side.
13. The radiation image-pickup device according to claim 12 , wherein, of the first and the second silicon oxide films, at least the first silicon oxide film includes the impurity element.
14. The radiation image-pickup device according to claim 1 , wherein the semiconductor layer includes polycrystal silicon, micro-crystal silicon, amorphous silicon, or an oxide semiconductor.
15. The radiation image-pickup device according to claim 14 , wherein the semiconductor layer comprises poly-silicon.
16. The radiation image-pickup device according to claim 1 , further comprising a wavelength conversion layer,
wherein the plurality of pixels each comprise a photoelectric conversion element, and
the wavelength conversion layer is provided on a light incident side of the plurality of pixels, and configured to convert the radiation to a wavelength in a sensitivity range of the photoelectric conversion element.
17. The radiation image-pickup device according to claim 1 , wherein the plurality of pixels each comprise a conversion layer configured to generate the signal charge by absorbing the radiation.
18. The radiation image-pickup device according to claim 1 , wherein the radiation comprises X-rays.
19. The radiation image-pickup device according to claim 1 , wherein the at least two transistors each further comprise a second nitride film laminated adjacent to the second silicon oxide film such that at least part of the second silicon oxide film is between the semiconductor layer and the second nitride film.
20. The radiation image-pickup device according to claim 1 , wherein the first nitride film comprises silicon nitride.