XRF analyzer for light element detection

Patent metadata

Field	Value
Publication number	US-10175184-B2
Application number	US-201615171803-A
Country	US
Kind code	B2
Filing date	Jun 2, 2016
Priority date	Jun 22, 2015
Publication date	Jan 8, 2019
Grant date	Jan 8, 2019

Abstract

The invention includes an XRF analyzer with reduced x-ray attenuation between sample and target and between sample and detector. Attenuation can be reduced by removing atmospheric-air paths through which the x-rays must travel. Reduced x-ray attenuation can allow for easier detection of low-atomic-number elements. Cost saving can be achieved by reducing the number of x-ray windows.

First claim

What is claimed is:

1. An x-ray fluorescence (XRF) analyzer comprising:
an enclosure including an interior capable of having a single vacuum therein;
a window, for transmission of x-rays, hermetically sealed to the enclosure;
a source located within the interior of the enclosure, the source including an electron emitter and a target electrically insulated from each other, the electron emitter capable of emitting electrons towards the target and the target capable of emitting x-rays towards the window in response to impinging electrons;
a detector, located within the interior of the enclosure, facing the window and capable of receiving and detecting x-rays emitted through the window;
a barrier located between the detector and the source and positioned to block x-rays, emitted from the source, from hitting the detector, the barrier comprising tungsten; and
an analyzer electrically-coupled to the detector, the analyzer capable of receiving a signal from the detector, the signal based on x-rays impinging on the detector, and analyzing the signal to determine a material composition of a sample.

2. The XRF analyzer of claim 1 , wherein the window includes:
a stack of thin film layers including an aluminum layer, a polyimide layer, and a corrosion-barrier layer;
the corrosion-barrier layer comprises a material selected from the list consisting of amorphous carbon or hexamethyldisilazane; and
the corrosion-barrier layer faces an exterior of the enclosure.

3. The XRF analyzer of claim 1 , further comprising:
the source and the detector angled towards a sample location;
the source and the detector attached to and supported by a triangle-shaped support on one side and attached to and supported by the enclosure on an opposite side; and
the barrier attached to and extending from the triangle-shaped support.

4. The XRF analyzer of claim 3 , wherein:
a plane aligned with a face of the window defines a window-plane;
a plane aligned with a face of the target defines a target-plane; and
an angle of intersection between the window-plane and the target-plane is less than 45 degrees.

5. The XRF analyzer of claim 1 , further comprising a first solid-material-free straight-line path from the detector to the window and a second solid-material-free straight-line path from the target to the window.

6. The XRF analyzer of claim 1 , further comprising:
a target-opening in the enclosure and a target-door, a source-filter-opening in the enclosure and a source-filter-door, a detector-filter-opening in the enclosure and a detector-filter-door, or combinations thereof;
the target-opening adjacent to the target and located to allow removal and insertion of the target, the source-filter-opening sized and located to allow removal and insertion of a filter between the target and the window, the detector-filter-opening sized and located to allow removal and insertion of a filter between the detector and the window, or combinations thereof; and
the target-door having a size and material for a hermetic seal to the enclosure at the target-opening and being openable or removable for insertion or removal of the target through the target-opening; the source-filter-door having a size and material for a hermetic seal to the enclosure at the source-filter-opening and being openable or removable for insertion or removal of the filter through the source-filter-opening; the detector-filter-door having a size and material for a hermetic seal to the enclosure at the detector-filter-opening, the detector-filter-door being openable or removable for insertion or removal of the filter through the detector-filter-opening; or combinations thereof.

7. An x-ray fluorescence (XRF) analyzer comprising:
an enclosure including an interior capable of having a single vacuum therein;
a window, for transmission of x-rays, hermetically sealed to the enclosure;
a source located within the interior of the enclosure, the source including an electron emitter and a target electrically insulated from each other, the electron emitter capable of emitting electrons towards the target and the target capable of emitting x-rays towards the window in response to impinging electrons;
a detector located within the interior of the enclosure, facing the window and capable of receiving and detecting x-rays emitted through the window;
an analyzer electrically-coupled to the detector, the analyzer capable of receiving a signal from the detector, the signal based on x-rays impinging on the detector, and analyzing the signal to determine a material composition of a sample;

a target-opening in the enclosure and a target-door, a source-filter-opening in the enclosure and a source-filter-door, a detector-filter-opening in the enclosure and a detector-filter-door, or combinations thereof;
the target-opening adjacent to the target, and located to allow removal and insertion of the target, the source-filter-opening sized and located to allow removal and insertion of a filter between the target and the window, the detector-filter-opening sized and located to allow removal and insertion of a filter between the detector and the window, or combinations thereof;

the target-door having a size and material for a hermetic seal to the enclosure at the target-opening and being openable or removable for insertion or removal of the target through the target-opening; the source-filter-door having a size and material for a hermetic seal to the enclosure at the source-filter-opening and being openable or removable for insertion or removal of the filter through the source-filter-opening; the detector-filter-door having a size and material for a hermetic seal to the enclosure at the detector-filter-opening, the detector-filter-door being openable or removable for insertion or removal of the filter through the detector-filter-opening; or combinations thereof.

8. The XRF analyzer of claim 7 , further comprising a vacuum pump attached to a pump-port in the enclosure, the vacuum pump capable of drawing a vacuum within the interior of the enclosure.

9. The XRF analyzer of claim 7 , further comprising the source and the detector attached to and supported by a triangle-shaped support on one side and attached to and supported by the enclosure on an opposite side.

10. The XRF analyzer of claim 7 , further comprising a first solid-material-free straight-line path from the detector to the window and a second solid-material-free straight-line path from the target to the window.

11. The XRF analyzer of claim 7 , wherein the XRF analyzer comprises the target-opening and the target-door.

12. The XRF analyzer of claim 7 , wherein the XRF analyzer comprises the source-filter-opening and the source-filter-door.

13. The XRF analyzer of claim 7 , wherein the XRF analyzer comprises the detector-filter-opening and the detector-filter-door.

14. An x-ray fluorescence (XRF) analyzer comprising:
an enclosure including an interior capable of having a single vacuum therein;
a window, for transmission of x-rays, hermetically sealed to the enclosure;
a source located within the interior of the enclosure, the source including an electron emitter and a target electrically insulated from each other, the electron emitter capable of emitting electrons towards the target and the target capable of emitting x-rays towards the window in response to impinging electrons;
a detector, located within the interior of the enclosure, facing the window and capable of receiving and detecting x-rays emitted through the window;
an analyzer electrically-coupled to the detector, the analyzer capable of receiving a signal from the detector, the signal bas

Assignees

• Moxtek Inc

Inventors

• Creighton Richard
• Morris Steven
• Chin Shawn
• Kamtekar Sanjay

Classifications

• H01J35/24

  Tubes wherein the point of impact of the cathode ray on the anode or anticathode is movable relative to the surface thereof · CPC title

• G01N2223/317

  windows · CPC title

• G01N23/223 Primary

  by irradiating the sample with X-rays or gamma-rays and by measuring X-ray fluorescence · CPC title