Transmission-type X-ray target and radiation generating tube including the same

Patent metadata

Field	Value
Publication number	US-9502204-B2
Application number	US-201414157403-A
Country	US
Kind code	B2
Filing date	Jan 16, 2014
Priority date	Jan 18, 2013
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

A transmission-type X-ray target includes a flat plate-shaped diamond substrate having a first surface and a second surface facing the first surface and a target layer that is located on the first surface. A residual stress of the first surface is lower than a residual stress of the second surface.

First claim

What is claimed is:

1. A transmission-type X-ray target comprising:
a flat plate-shaped diamond substrate having a first surface, a second surface opposing the first surface, and a side surface between the first and second surface; and
a target layer located on the first surface, wherein an angle between the first surface and the side surface and an angle between the second surface and the side surface are so configured such that a residual stress of the first surface is lower than a residual stress of the second surface.

2. The transmission-type X-ray target according to claim 1 , wherein, in a case where a distribution of residual stress exists on each of the first surface and the second surface, the residual stress of the first surface is lower than the residual stress of the second surface if and only if a maximum residual stress of the first surface is lower than a maximum residual stress of the second surface.

3. The transmission-type X-ray target according to claim 1 , wherein the diamond substrate further has a side surface, and wherein an angle between the first surface and the side surface is larger than an angle between the second surface and the side surface.

4. The transmission-type X-ray target according to claim 1 , wherein the angle between the first surface and the side surface is an obtuse angle.

5. The transmission-type X-ray target according to claim 1 , wherein the diamond substrate is a single-crystal diamond.

6. The transmission-type X-ray target according to claim 5 , wherein the diamond substrate is made by separating a part of a base material, which is made of a single-crystal, from the base material.

7. The transmission-type X-ray target according to claim 6 , wherein the diamond substrate is made by separating a part of the base material from the base material by irradiation of local heating light.

8. The transmission-type X-ray target according to claim 1 , wherein a layer thickness of the target layer is in the range of 1 μm to 20 μm.

9. The transmission-type X-ray target according to claim 1 , further comprising:
an electrode disposed on the diamond substrate so as to extend from a periphery of the target layer to a periphery of the diamond substrate, the periphery of the target layer being distant from the periphery of the diamond substrate.

10. The transmission-type X-ray target according to claim 9 , wherein the electrode includes a metallic element having a negative standard free energy of formation of carbide.

11. The transmission-type X-ray target according to claim 10 , wherein the electrode includes titanium, zirconium, or chromium.

12. The transmission-type X-ray target according to claim 9 , wherein a layer thickness of the electrode is in the range of 100 nm to 10 μm.

13. A target structure comprising:
the transmission-type X-ray target according to claim 3 ; and
an anode member that is located along at least one of the side surface and a periphery of the first surface and that is electrically connected to the target layer.

14. The target structure according to claim 13 , wherein the target layer and the anode member are electrically connected to each other through a brazed joint.

15. A radiation generating tube comprising:
the transmission-type X-ray target according to claim 1 ;
an electron emitting source including an electron emitting unit facing the target layer; and
an insulating pipe that electrically insulates the target layer and the electron emitting source from each other.

16. A radiation generating device comprising:
the radiation generating tube according to claim 15 ; and
a drive circuit electrically connected to each of the target layer and the electron emitting unit, the drive circuit outputting a tube voltage applied across the target layer and the electron emitting unit.

17. A radiographic apparatus comprising:
the radiation generating device according to claim 16 ;
a radiation detector that detects radiation generated by the radiation generating device; and
a control unit that integrally controls the radiation generating device and the radiation detector.

18. A transmission-type X-ray target comprising:
a flat plate-shaped diamond substrate having a first surface and a second surface opposite to the first surface; and
a target layer located on the first surface, wherein the flat plate-like shaped diamond substrate is configured with a cross-sectional shape such that a residual stress of the first surface is lower than a residual stress of the second surface.

19. The transmission-type X-ray target according to claim 18 , wherein, in a case where a distribution of residual stress exists on each of the first surface and the second surface, the residual stress of the first surface is lower than the residual stress of the second surface if and only if a maximum residual stress of the first surface is lower than a maximum residual stress of the second surface.

20. The transmission-type X-ray target according to claim 18 , wherein the diamond substrate further has a side surface, and wherein an angle between the first surface and the side surface is larger than an angle between the second surface and the side surface.

21. The transmission-type X-ray target according to claim 18 , wherein the angle between the first surface and the side surface is an obtuse angle.

22. The transmission-type X-ray target according to claim 18 , wherein the diamond substrate is a single-crystal diamond.

23. The transmission-type X-ray target according to claim 22 , wherein the diamond substrate is made by separating a part of a base material, which is made of a single-crystal, from the base material.

24. The transmission-type X-ray target according to claim 23 , wherein the diamond substrate is made by separating a part of the base material from the base material by irradiation of local heating light.

25. The transmission-type X-ray target according to claim 18 , wherein a layer thickness of the target layer is in the range of 1 μm to 20 μm.

26. The transmission-type X-ray target according to claim 18 , further comprising:
an electrode disposed on the diamond substrate so as to extend from a periphery of the target layer to a periphery of the diamond substrate, the periphery of the target layer being distant from the periphery of the diamond substrate.

27. The transmission-type X-ray target according to claim 26 , wherein the electrode includes a metallic element having a negative standard free energy of formation of carbide.

28. The transmission-type X-ray target according to claim 27 , wherein the electrode includes titanium, zirconium, or chromium.

29. The transmission-type X-ray target according to claim 26 , wherein a layer thickness of the electrode is in the range of 100 nm to 10 μm.

30. A target structure comprising:
the transmission-type X-ray target according to claim 20 ; and
an anode member that is located along at least one of the side surface and a periphery of the first surface and that is electrically connected to the target layer.

31. The target structure according to claim 30 , wherein the target layer and the anode member are electrically connected to each other through a brazed joint.

32. A radiation generating tube comprising:
the transmission-type X-ray target according to claim 18 ;
an electron

Assignees

• Canon Kk

Inventors

• Ikarashi Yoichi
• Ogura Takao
• Tsukamoto Takeo

Classifications

• H01J2235/084

  Target-substrate interlayers or structures, e.g. to control or prevent diffusion or improve adhesion · CPC title

• H01J35/02

  Details · CPC title

• H01J2235/087

  Electricity · mapped topic

• H01J35/08 Primary

  Anodes; Anti cathodes · CPC title

• H01J35/116 Primary

  Transmissive anodes (acting as a window H01J35/186) · CPC title