OPTICAL AXIS ADJUSTMENT METHOD FOR X-RAY ANALYZER AND X-RAY ANALYZER

• US 20150146859A1
• Filed: 11/05/2014
• Published: 05/28/2015
• Est. Priority Date: 11/25/2013
• Status: Active Grant

• Current Assignee: Rigaku Corporation
• Original Assignee: Rigaku Corporation
• Inventors: KAKEFUDA, Kouji, Tobita, Ichiro
• Granted Patent: US 9,442,084 B2
• Time in Patent Office: Days
• US Class Current: 378/75
• CPC Class Codes: G01N 2223/303 calibrating, standardising
• CPC Class Codes: G01N 23/20016 Goniometers
• CPC Class Codes: G01N 23/207 Diffractometry using detectors, e.g. using a probe in a central position and one or more displaceable detectors in circumferential positions

Abstract

An optical axis adjustment method for an X-ray analyzer. In a 2θ-adjustment step, a 0° position of the rotation of a receiving-side arm and a 0° position of the angle of diffraction 2θ are aligned. In a Zs-axis adjustment step, the position of an incident-side slit along a direction orthogonal to the centerline of the X-rays incident upon a sample from an X-ray source is adjusted. In a θ-adjustment step, the centerline of X-rays incident upon the sample from the X-ray source and the surface of the sample are adjusted so as to be parallel. In the 2θ-adjustment step, the Zs-axis adjustment step, and the θ-adjustment step, the capability for X-ray intensity positional resolution upon a straight line possessed by a one-dimensional X-ray detector is used to perform 2θ-adjustment, Zs-axis adjustment, and θ-adjustment.

Claims

1. An optical axis adjustment method for an X-ray analyzer,

(A) the X-ray analyzer comprising:

an incident-side arm that rotates around a sample axis passing through a sample position constituting a position at which a sample is placed;

a receiving-side arm that rotates around the sample axis and extends toward a side opposite the incident-side arm;

an X-ray source provided on the incident-side arm;

an incident-side slit provided on the incident-side arm between the sample position and the X-ray source; and

an X-ray detector, provided on the receiving-side arm, and possessing X-ray intensity positional resolution, which is a function of detecting X-ray intensity within predetermined regions on a straight line,

wherein;

an angle of incidence of X-rays incident upon the sample from the X-ray source is an angle of incidence θ

; and

an angle formed by the centerline of X-rays diffracted by the sample and the centerline of X-rays incident upon the sample is an angle of diffraction 2θ

,

(B) the optical axis adjustment method comprising;

a 2θ

-adjustment step in which a 0°

position of the rotation of the receiving-side arm and a 0°

position of the angle of diffraction 2θ

are aligned;

a Zs-axis adjustment step in which the position of the incident-side slit along a direction orthogonal to the centerline of X-rays incident upon the sample from the X-ray source is adjusted; and

a θ

-adjustment step of adjusting the centerline of the X-rays incident upon the sample from the X-ray source and the surface of the sample so as to be parallel,

wherein in the 2θ

-adjustment step, the Zs-axis adjustment step, and the θ

-adjustment step, the capability for X-ray intensity position resolution upon a straight line possessed by the X-ray detector is used to perform 2θ

-adjustment, Zs-axis adjustment, and θ

-adjustment, respectively.

2. The X-ray analyzer optical axis adjustment method according to claim 1, wherein:

X-ray intensities for a plurality of different 2θ

angle values in an X-ray receiving region of the X-ray detector are found simultaneously using the X-ray detector; and

an amount of angle deviation for 2θ

-adjustment, an amount of incident-side slit positional deviation for Zs-axis adjustment, and an amount of deviation in parallelism for θ

-adjustment are found on the basis of the found X-ray intensities.

3. The X-ray analyzer optical axis adjustment method according to claim 1, wherein:

during the 2θ

-adjustment step;

a center slit is disposed on the sample position,

the incident-side arm is placed at a position at which the angle of incidence θ

is 0°

,

the receiving-side arm is placed at a position at which the angle of diffraction 2θ

is 0°

,

the incident-side slit is set to an open state,

X-rays emitted by the X-ray source pass through the incident-side slit and the center slit and become incident upon the X-ray detector,

the amount of deviation between a position at which the X-rays are incident in the X-ray detector and a position at which the angle of diffraction 2θ

is 0°

is obtained, and

the optical axis of the X-rays is adjusted either by moving the position of the receiving-side arm by the amount of deviation, or by correcting data obtained for the angle of diffraction 2θ

by the X-ray detector by the amount of deviation.

4. The X-ray analyzer optical axis adjustment method according to claim 3, wherein:

the Zs-axis adjustment step is performed after the optical axis of the X-rays is corrected by the amount of deviation in the 2θ

-adjustment step; and

in the Zs-axis adjustment step;

the center slit is removed from the sample position,

the incident-side slit is disposed at a plurality of different positions along a direction orthogonal to the centerline of X-rays incident upon the sample from the X-ray source,

X-rays are incident upon the X-ray detector through the incident-side slit at each of the plurality of different positions,

the position of the incident-side slit at which the angle of diffraction 2θ

is 0°

is calculated from the positions at which the incident-side slit is placed and the X-ray profiles detected by the X-ray detector, and

the incident-side slit is moved to and disposed at the calculated position.

5. The X-ray analyzer optical axis adjustment method according to claim 1, wherein:

in the θ

-adjustment step;

an optical axis adjustment jig or a sample is placed on the sample position,

the incident-side arm is placed at a position at which the angle of incidence θ

is 0°

,

the receiving-side arm is placed at a position at which the angle of diffraction 2θ

is 0°

,

X-rays are made to become incident upon the surface of the sample at a plurality of different angles of incidence θ

, and X-ray intensity is measured at each of the angles using the X-ray detector,

a value for an angle of incidence θ

at which the X-rays are parallel with the surface of the sample is calculated on the basis of the values for the angle of incidence θ and

the results detected by the X-ray detector, and

the position of the incident-side arm is corrected according to the calculated angle of incidence θ

.

8. The X-ray analyzer optical axis adjustment method according to claim 2, wherein:

during the 2θ

-adjustment step;

a center slit is disposed on the sample position,

the incident-side arm is placed at a position at which the angle of incidence θ

is 0°

,

the receiving-side arm is placed at a position at which the angle of diffraction 2θ

is 0°

,

the incident-side slit is set to an open state,

X-rays emitted by the X-ray source pass through the incident-side slit and the center slit and become incident upon the X-ray detector,

the amount of deviation between a position at which the X-rays are incident in the X-ray detector and a position at which the angle of diffraction 2θ

is 0°

is obtained, and

the optical axis of the X-rays is adjusted either by moving the position of the receiving-side arm by the amount of deviation, or by correcting data obtained for the angle of diffraction 2θ

by the X-ray detector by the amount of deviation.

9. The X-ray analyzer optical axis adjustment method according to claim 8, wherein:

the Zs-axis adjustment step is performed after the optical axis of the X-rays is corrected by the amount of deviation in the 2θ

-adjustment step; and

in the Zs-axis adjustment step;

the center slit is removed from the sample position,

the incident-side slit is disposed at a plurality of different positions along a direction orthogonal to the centerline of X-rays incident upon the sample from the X-ray source,

X-rays are incident upon the X-ray detector through the incident-side slit at each of the plurality of different positions,

the position of the incident-side slit at which the angle of diffraction 2θ

is 0°

is calculated from the positions at which the incident-side slit is placed and the X-ray profiles detected by the X-ray detector, and

the incident-side slit is moved to and disposed at the calculated position.

10. The X-ray analyzer optical axis adjustment method according to claim 9, wherein:

in the θ

-adjustment step;

an optical axis adjustment jig or a sample is placed on the sample position,

the incident-side arm is placed at a position at which the angle of incidence θ

is 0°

,

the receiving-side arm is placed at a position at which the angle of diffraction 2θ

is 0°

,

X-rays are made to become incident upon the surface of the sample at a plurality of different angles of incidence θ

, and X-ray intensity is measured at each of the angles using the X-ray detector,

a value for an angle of incidence θ

at which the X-rays are parallel with the surface of the sample is calculated on the basis of the values for the angle of incidence θ and

the results detected by the X-ray detector, and

the position of the incident-side arm is corrected according to the calculated angle of incidence θ

.

6. An X-ray analyzer comprising:

an incident-side arm that rotates around a sample axis passing through a sample position constituting a position at which a sample is placed;

a receiving-side arm that rotates around the sample axis and extends toward a side opposite the incident-side arm;

an X-ray source provided on the incident-side arm;

an incident-side slit provided on the incident-side arm between the sample position and the X-ray source; and

an X-ray detector, provided on the receiving-side arm, and possessing X-ray intensity positional resolution, which is a function of detecting X-ray intensity in each predetermined region on a straight line;

wherein;

an angle of incidence of X-rays incident upon the sample from the X-ray source is angle of incidence θ

;

an angle formed by the centerline of X-rays diffracted by the sample and the centerline of X-rays incident upon the sample is angle of diffraction 2θ

;

the X-ray analyzer further comprising;

2θ

-adjustment means for performing adjustment so that a 0°

position of the rotation of the receiving-side arm and a 0°

position of the angle of diffraction 2θ

are aligned;

Zs-axis adjustment means for adjusting the position of the incident-side slit along a direction orthogonal to the centerline of X-rays incident upon the sample from the X-ray source; and

θ

-adjustment means for adjusting the centerline of X-rays incident upon the sample from the X-ray source and the surface of the sample so as to be parallel; and

the 2θ

-adjustment means, the Zs-axis adjustment means, and the θ

-adjustment means perform 2θ

-adjustment, Zs-axis adjustment, and θ

-adjustment, respectively, using the capability for X-ray intensity positional resolution on a straight line possessed by the X-ray detector.

7. The X-ray analyzer according to claim 6, wherein:

(A) the 2θ

-adjustment means;

simultaneously finds X-ray intensities for a plurality of different 2θ

angle values in an X-ray receiving region of the X-ray detector by using the X-ray detector, and

finds the amount of angle deviation for 2θ

-adjustment on the basis of the found X-ray intensities,

(B) the Zs-axis adjustment means;

simultaneously finds X-ray intensity for a plurality of different 2θ

angle values in an X-ray receiving region of the X-ray detector by using the X-ray detector, and

finds the amount of incident-side slit positional deviation for Zs-axis adjustment on the basis of the found X-ray intensities, and

(C) the θ

-adjustment means;

simultaneously finds X-ray intensity for a plurality of different 2θ

angle values in an X-ray receiving region of the X-ray detector by using the X-ray detector, and

finds the amount of deviation in parallelism for θ

-adjustment on the basis of the found X-ray intensities.