X-ray detection system

• US 8,421,007 B2
• Filed: 05/18/2011
• Issued: 04/16/2013
• Est. Priority Date: 05/18/2011
• Status: Active Grant

• Current Assignee: JEOL Limited, Tohoku University National Universities Corporation
• Original Assignee: JEOL Limited, Tohoku University National Universities Corporation
• Inventors: Terauchi, Masami, Murano, Takanori, Handa, Nobuo, Takahashi, Hideyuki
• Primary Examiner(s): Kim, Robert
• Assistant Examiner(s): MCCORMACK, JASON L
• Application Number:
  US13/110,214
• Publication Number:
  US 20120292508A1
• Time in Patent Office: 699 Days
• Field of Search: 250/305, 250/306, 250/307, 250/310, 250/311
• US Class Current: 250/305
• CPC Class Codes: G01N 23/2252 Measuring emitted X-rays, e.g. electron probe microanalysis [EPMA]
• CPC Class Codes: H01J 2237/24425 Wavelength-dispersive spectrometer
• CPC Class Codes: H01J 2237/28 Scanning microscopes
• CPC Class Codes: H01J 2237/2807 X-rays
• CPC Class Codes: H01J 2237/2808 Cathodoluminescence
• CPC Class Codes: H01J 37/244 Detectors; Associated components or circuits therefor

Abstract

An X-ray detection system has an electron beam irradiation portion, a diffraction grating, a splitter for distributing the direction of propagation of the diffracted X-rays such that an imaging plane for the diffracted X-rays is assigned to plural positions spaced apart in a direction perpendicular to the direction of energy dispersion of the diffracted X-rays, and image sensors different in energy sensitivity disposed respectively at the positions to which the imaging plane is assigned.

Claims

1. An X-ray detection system comprising:

electron beam irradiation means for irradiating a sample with an electron beam;

a diffraction grating that receives characteristic X-rays emitted from the irradiated sample and produces diffracted X-rays;

a splitter for distributing a direction of propagation of the diffracted X-rays such that an imaging plane for the diffracted X-rays is assigned to plural positions spaced apart in a direction perpendicular to a direction of energy dispersion of the diffracted X-rays; and

plural image sensors having a higher energy sensitivity and a lower energy sensitivity, respectively, and disposed respectively at the plural positions to which the imaging plane is assigned,

wherein said splitter has a tubular X-ray guiding mirror portion made by mirrors for reflecting the diffracted X-rays, a movable mirror for distributing the direction of propagation of the diffracted X-rays in a branching portion of the guiding mirror portion, and a movable mirror controller for controlling a position of the movable mirror.

2. An X-ray detection system as set forth in claim 1, wherein said image sensor having said higher energy sensitivity is an X-ray image sensor, and wherein said image sensor having said lower energy sensitivity is an image sensor having a microchannel plate subassembly on its light-sensitive surface.

3. An X-ray detection system as set forth in claim 2, wherein said microchannel plate subassembly has a higher quantization efficiency in a soft X-ray region than in a cathodoluminescence region.

4. An X-ray detection system as set forth in any one of claims 2 or 3, further comprising:

a tiltably-and-rotatably holding portion for holding the microchannel plate subassembly such that the subassembly is rotatable while being tilted relative to the direction of propagation of the diffracted X-rays; and

a rotation control portion for rotating the microchannel plate subassembly while the subassembly is held by the tiltably-and-rotatably holding portion.

5. An X-ray detection system as set forth in any one of claims 1, 2, or 3, wherein said diffraction grating is a varied line-space (VLS) diffraction grating.