Curved X-ray reflector

• US 7,415,096 B2
• Filed: 07/25/2006
• Issued: 08/19/2008
• Est. Priority Date: 07/26/2005
• Status: Active Grant

• Current Assignee: Bruker Technologies Ltd. (Bruker Corporation)
• Original Assignee: Jordan Valley Semiconductors Ltd. (Bruker Corporation)
• Inventors: Sherman, Dov
• Primary Examiner(s): SONG, HOON K
• Application Number:
  US11/491,962
• Publication Number:
  US 20070025511A1
• Time in Patent Office: 756 Days
• Field of Search: 378 84- 85, 378/70, 378/71
• US Class Current: 378/84
• CPC Class Codes: G21K 1/06 using diffraction, refraction or reflection, e.g. monochromators G21K1/10, G21K7/00 take precedence
• CPC Class Codes: G21K 2201/064 having a curved surface
• CPC Class Codes: G21K 2201/067 Construction details

Abstract

A method for producing X-ray optics includes providing a wafer of crystalline material having front and rear surfaces and a lattice spacing suitable for reflecting incident X-rays of a given wavelength. A thin film is deposited on the front surface of the wafer so as to generate compressive forces in the thin film sufficient to impart a concave curvature to the rear surface of the wafer with at least one radius of curvature selected for focusing the incident X-rays.

Claims

1. A method for producing X-ray optics, comprising:

providing a wafer of crystalline material having front and rear surfaces and a lattice spacing suitable for reflecting incident X-rays of a given wavelength; and

depositing a thin film on the front surface of the wafer so as to generate compressive forces in the thin film sufficient to impart a concave curvature to the rear surface of the wafer with at least one radius of curvature selected for focusing the incident X-rays.

2. The method according to claim 1, wherein providing the wafer comprises providing a silicon wafer, and wherein depositing the thin film comprises depositing a metal film on the wafer.

3. The method according to claim 2, wherein the metal film comprises at least one of tungsten and titanium.

4. The method according to claim 1, wherein depositing the thin film comprises forming stripes of the thin film on the front surface, the stripes having a thickness, width and spacing selected to create the at least one selected radius of curvature.

5. The method according to claim 4, wherein the thickness, width and spacing of the stripes are chosen so as to impart to the wafer a first radius of curvature about a first curvature axis and a second radius of curvature, different from the first radius of curvature, about a second curvature axis.

6. The method according to claim 4, wherein forming the stripes comprises sputtering the thin film onto the front surface and then etching the thin film.

7. The method according to claim 1, and comprising thinning the rear surface of the wafer after depositing the thin film, so that the thinned wafer curves to the selected radius of curvature.

8. An X-ray optic, comprising:

a wafer of crystalline material having front and rear surfaces and a lattice spacing suitable for reflecting incident X-rays of a given wavelength; and

a thin film deposited on the front surface of the wafer, having compressive forces in the thin film sufficient to impart a concave curvature to the rear surface of the wafer with at least one radius of curvature selected for focusing the incident X-rays.

9. The optic according to claim 8, wherein the wafer comprises silicon, and wherein the thin film comprises a metal.

10. The optic according to claim 9, wherein the metal film comprises at least one of tungsten and titanium.

11. The optic according to claim 8, wherein the thin film comprises stripes of the thin film, the stripes having a thickness, width and spacing selected to create the at least one selected radius of curvature.

12. The optic according to claim 11, wherein the thickness, width and spacing of the stripes are chosen so as to impart to the wafer a first radius of curvature about a first curvature axis and a second radius of curvature, different from the first radius of curvature, about a second curvature axis.

13. The optic according to claim 11, wherein the stripes are formed by sputtering the thin film onto the front surface and then etching the thin film.

14. The optic according to claim 8, wherein the rear surface of the wafer is thinned after depositing the thin film, so that the thinned wafer curves to the selected radius of curvature.

15. An X-ray spectrometer, comprising:

an X-ray source, which is operative to emit a beam of X-rays of a given wavelength;

an X-ray optic, which is configured and positioned to focus the beam of X-rays onto a sample, and which comprises;

a wafer of crystalline material having front and rear surfaces and a lattice spacing suitable for reflecting the X-rays of the given wavelength; and

a thin film deposited on the front surface of the wafer, having compressive forces in the thin film sufficient to impart a concave curvature to the rear surface of the wafer with at least one radius of curvature selected for focusing the X-ray beam.