CN116500065A - A Micro-Single Crystal Unit Cell Parameter Measuring Instrument - Google Patents

Abstract

The invention provides a micro single crystal unit cell parameter measuring instrument and an operation method, wherein the measuring instrument comprises the following components: the X-ray detector comprises a measuring instrument main board, an X-ray tube fixing device, an X-ray collimator capable of adjusting the output size of X-rays, a sample video microscope, a sample table and an X-ray detector; the X-ray tube and the X-ray collimator are fixed on a main board of the measuring instrument through the fixing device, and after the output size of X-rays emitted by the X-ray tube is regulated by the X-ray collimator, the X-rays irradiate a micro single crystal sample on the sample table and then are reflected to the X-ray detector by the crystal sample; the sample stage and the X-ray detector are also arranged on the main board of the measuring instrument; by adopting the method of the invention, the installation and adjustment of the tiny monocrystal are very simple under the assistance of a system video microscope. The accuracy and repeatability of cell parameter measurement are greatly improved. The intelligent software design simplifies the measurement flow, so that a user can finish the measurement of the cell parameters by one-key operation.

Description

A Micro-Single Crystal Unit Cell Parameter Measuring Instrument

technical field

The invention belongs to the technical field of single crystal unit cell detection and relates to a tiny single crystal unit cell parameter measuring instrument.

Background technique

X-ray diffractometer uses the principle of diffraction to accurately measure the crystal structure, texture and stress of substances, and accurately perform phase analysis, qualitative analysis, and quantitative analysis. Widely used in metallurgy, petroleum, chemical industry, scientific research, aerospace, teaching, material production and other fields.

X-ray diffractometers come in various forms and have different uses, but their basic composition is very similar, and the main components include 4 parts.

(1) The X-ray source provides the X-rays required for measurement. Changing the anode target material of the X-ray tube can change the wavelength of X-rays, and adjusting the anode voltage can control the intensity of the X-ray source.

(2) The sample and the adjustment mechanism system of the sample position and orientation, the sample includes: single crystal, powder, polycrystalline or microcrystalline solid block.

(3) The radiation detector detects the diffraction intensity or detects the diffraction direction at the same time, and the diffraction pattern data can be obtained through the instrument measurement recording system or computer processing system.

The measurement of unit cell parameters of tiny single crystals usually adopts the method of diffractometer, and uses the measurement of the diffraction peak position of a certain crystal plane and the Bragg formula to calculate the unit cell parameters. Since the diffraction crystal plane of a single crystal must strictly meet the Bragg conditions to generate a diffraction signal, this places strict requirements on the placement and adjustment of the single crystal. During the measurement process, it is necessary to continuously adjust the inclination angle and rotation angle of the sample to find the sample position that satisfies the diffraction geometry. Ordinary diffractometers do not have such a sample adjustment mechanism. Some special diffractometers can realize the sample adjustment function, but there are great defects in the degree of automation and optimization of the adjustment, which makes the measurement process very cumbersome and slow, and is not suitable for routine detection of such samples. In addition, due to the small size of the tiny single crystal, the adjustment and placement of the sample need to be completed with the help of a microscope, and all diffractometers do not have a video system with sufficient magnification.

Contents of the invention

In order to solve the above-mentioned technical problems, the first aspect of the present invention proposes a tiny single crystal unit cell parameter measuring instrument, the measuring instrument includes: the main board of the measuring instrument, the fixing device of the X-ray light tube, the X-ray tube capable of adjusting the output size of the X-ray Ray collimator, sample video microscope, sample stage and X-ray detector;

The X-ray tube and X-ray collimator are fixed on the main board of the measuring instrument through a fixing device. The X-ray emitted by the X-ray tube is irradiated to the tiny single crystal sample on the sample stage after the X-ray collimator adjusts the output size, and then is captured by the crystal. The sample is reflected to the X-ray detector; the sample stage and X-ray detector are also mounted on the main board of the measuring instrument.

According to the unit cell parameter measuring instrument according to the first aspect of the present invention, the fixing device of the X-ray light tube includes a three-dimensional position adjustment device, a manual slide table and an X-ray light tube tilting device.

According to the unit cell parameter measuring instrument according to the first aspect of the present invention, the sample stage includes: a tilting and rotating device for the tiny single crystal sample, an adjuster for the height and horizontal position of the sample;

The tilting and rotating mechanism is driven by a stepper motor;

The adjuster of sample height and horizontal position is a manual adjustment structure, which can provide height lifting, and vertical and horizontal position movement on the horizontal plane.

In the unit cell parameter measuring instrument according to the first aspect of the present invention, the tilting and rotating mechanism uses a turntable structure of a high-precision worm gear.

In the unit cell parameter measuring instrument according to the first aspect of the present invention, the X-ray detector adopts a small one-dimensional or two-dimensional array detector;

The X-ray detector is fixed on the driving device, the driving device is installed on the main board of the measuring instrument, and there is a preset angle between the connection line from the surface of the X-ray detector to the sample stage and the X-ray emitted by the X-ray tube; There is a predetermined distance between the surface of the X-ray detector and the sample stage; the driving device can drive the X-ray detector to adjust within a predetermined area, so that the normal and axis of the X-ray detector surface and the X-ray tube emitted by the X-ray detector can be changed. The included angle of the X-ray.

According to the unit cell parameter measuring instrument according to the first aspect of the present invention, the driving device is driven by a harmonic geared motor or a common geared motor.

The unit cell parameter measuring instrument according to the first aspect of the present invention, the measuring instrument also includes a sample video microscope, the sample video microscope is connected with a display with a crosshair, and the sample video microscope and the display are used to observe sample.

A second aspect of the present invention proposes a method of operating a tiny single crystal unit cell parameter measuring instrument, said method comprising the steps of:

Step 1. Take the tiny single crystal out of the sample box with a needle tip, and transfer it to a plastic sample holder with a magnet base after viewing it under an observation microscope;

Step 2, transfer the sample holder carrying the tiny single crystal to the magnetic base of the sample stage, roughly adjust the position of the tiny single crystal so that the tiny single crystal is located near the crosshairs of the display, and then finely adjust the center of the tiny single crystal and the crosshairs coincident center;

Step 3. Tilt the tiny single crystal to 90 degrees, and adjust the height of the tiny single crystal so that the upper surface of the tiny single crystal coincides with the horizontal line of the crosshair on the display screen;

Step 4, open the measurement software, click the start measurement button, and start the test procedure;

Step 5, after the measurement is over, remove the sample holder.

According to the method described in the second aspect of the present invention, step 2 includes: using the manual adjustment structure of the sample stage to move the position of the tiny single crystal in the vertical and horizontal directions on the height and horizontal plane.

As the method described in the second aspect of the present invention, the test procedure of step 5 includes:

Step 5.1, automatically changing the inclination and rotation of the tiny single crystal with a preset step size, and detecting the diffraction intensity of X-rays on the tiny single crystal;

Step 5.2, after the diffraction peak is found, repeat the tilt and rotation of the tiny single crystal with a step size smaller than the preset step size near the diffraction peak, and measure the spectral line of the diffraction peak;

Step 5.3, calculating the exact position of the diffraction peak of the tiny single crystal, and writing it into a specified measurement result file.

By adopting the method of the invention, the installation and adjustment of the tiny single crystal becomes very simple with the assistance of the system video microscope. Using a micro-focus spot light source combined with a collimator, the measurement intensity of a tiny single crystal is greatly improved. The motor-driven sample tilt and rotation design allows the acquisition of diffraction signals to be automated and programmed. The X-ray array detector design greatly improves the accuracy and repeatability of unit cell parameter measurement. The intelligent software design simplifies the measurement process, reduces human intervention, and truly realizes one-key operation.

Description of drawings

Fig. 1 is a structural schematic diagram of the micro single crystal measuring instrument of the present invention.

Among them, 1. The main board of the measuring instrument; 2. The device for fixing the X-ray light tube; 3. The X-ray collimator; 4. The tilting and rotating mechanism of the sample; 5. The manual regulator of the sample; 6. The video microscope of the sample; 7. Sample table turntable system; 8. Detector drive system; 9. X-ray detector.

Detailed ways

In order to solve the problem of unit cell parameter measurement of tiny single crystals, the present invention designs a brand-new tiny single crystal measurement system, which uses a high-brightness micro-focus spot X-ray source and an X-ray collimation system that can adjust the diameter of the outgoing X-rays , 5-axis sample adjustment system, in which the tilt and rotation of the sample is driven by a stepper motor. Equipped with a high-magnification microscope with a magnification of 100-200 times for adjusting the sample, the high-magnification microscope can provide high-definition video output of more than 1024 pixels. The detector is a one-dimensional or two-dimensional array X-ray detector. The software of this system can realize the automatic operation of the whole measurement without human intervention, and truly realize the one-key operation of the measurement of the parameters of the tiny single crystal unit cell.

The specific implementation manners of the present invention will be described in detail below in conjunction with the accompanying drawings.

The first aspect of the present invention proposes a tiny single crystal unit cell parameter measuring instrument, the measuring instrument includes: the main board of the measuring instrument, the fixing device of the X-ray light tube, the X-ray collimator capable of adjusting the output size of the X-ray, and the sample Video microscope, sample stage and X-ray detector;

The X-ray tube and X-ray collimator are fixed on the main board of the measuring instrument through a fixing device. The X-ray emitted by the X-ray tube is irradiated to the tiny single crystal sample on the sample stage after the X-ray diameter is adjusted by the X-ray collimator, and then The crystal sample is reflected to the X-ray detector; the sample stage and X-ray detector are also mounted on the main board of the measuring instrument.

According to the unit cell parameter measuring instrument according to the first aspect of the present invention, the fixing device of the X-ray light tube includes a three-dimensional position adjustment device, a manual slide table and an X-ray light tube tilting device.

According to the unit cell parameter measuring instrument according to the first aspect of the present invention, the sample stage includes: a tilting and rotating device for the tiny single crystal sample, an adjuster for the height and horizontal position of the sample;

The tilting and rotating mechanism is driven by a stepping motor; the tilting angle is 0-90 degrees.

The adjuster of sample height and horizontal position is a manual adjustment structure, which can provide height lifting, and vertical and horizontal position movement on the horizontal plane. The longitudinal and transverse adjustment lengths are 0-13 mm, and the minimum movement interval is 20 μm

In the unit cell parameter measuring instrument according to the first aspect of the present invention, the tilting and rotating mechanism uses a turntable structure of a high-precision worm gear.

In the unit cell parameter measuring instrument according to the first aspect of the present invention, the X-ray detector adopts a small one-dimensional or two-dimensional array detector;

The X-ray detector is fixed on the driving device, the driving device is installed on the main board of the measuring instrument, and there is a preset angle between the connection line from the surface of the X-ray detector to the sample stage and the X-ray emitted by the X-ray tube; There is a predetermined distance between the surface of the X-ray detector and the sample stage; the driving device can drive the X-ray detector to adjust within a predetermined area, so that the normal and axis of the X-ray detector surface and the X-ray tube emitted by the X-ray detector can be changed. The included angle of the X-ray. The distance between the driving device and the sample stage is 166 mm, and the included angle between the surface normal of the X-ray detector and the axis and the X-rays emitted by the X-ray tube is 132 degrees.

According to the unit cell parameter measuring instrument according to the first aspect of the present invention, the driving device is driven by a harmonic geared motor or a common geared motor.

The unit cell parameter measuring instrument according to the first aspect of the present invention, the measuring instrument also includes a sample video microscope, the sample video microscope is connected with a display with a crosshair, and the sample video microscope and the display are used to observe sample.

A second aspect of the present invention proposes a method of operating a tiny single crystal unit cell parameter measuring instrument, said method comprising the steps of:

Step 1. Take the tiny single crystal out of the sample box with a needle tip, and transfer it to a plastic sample holder with a magnet base after viewing it under an observation microscope;

Step 2, transfer the sample holder carrying the tiny single crystal to the magnetic base of the sample stage, roughly adjust the position of the tiny single crystal so that the tiny single crystal is located near the crosshairs of the display, and then finely adjust the center of the tiny single crystal and the crosshairs coincident center;

Step 3. Tilt the tiny single crystal to 90 degrees, and adjust the height of the tiny single crystal so that the upper surface of the tiny single crystal coincides with the horizontal line of the crosshair on the display screen;

Step 4, open the measurement software, click the start measurement button, and start the test procedure;

Step 5, after the measurement is over, remove the sample holder.

According to the method described in the second aspect of the present invention, step 2 includes: using the manual adjustment structure of the sample stage to move the position of the tiny single crystal in the vertical and horizontal directions on the height and horizontal plane.

As the method described in the second aspect of the present invention, the test procedure of step 5 includes:

Step 5.1, automatically changing the inclination and rotation of the tiny single crystal with a preset step size, and detecting the diffraction intensity of X-rays on the tiny single crystal;

Step 5.2, after the diffraction peak is found, repeat the tilt and rotation of the tiny single crystal with a step size smaller than the preset step size near the diffraction peak, and measure the spectral line of the diffraction peak;

Step 5.3, calculating the exact position of the diffraction peak of the tiny single crystal, and writing it into a specified measurement result file.

Example

The technical scheme adopted by the present invention is: a new installation structure of the diffractometer is designed. It includes the main board 1 of the measuring instrument, the fixing device 2 of the X-ray light tube and the position adjustment device. It includes a manual sliding table and a tilting structure of the light tube. The manual sliding table adopts a dovetail groove design, and moves with high-precision threads and bolts. The light pipe tilting device adopts a double-hole regulator, in which the lower hole is the fixing hole, and the fixing bolt is closely matched with the fixing hole, and the upper hole is a slot hole, and the fixing bolt can have a certain degree of freedom in it. Degree can realize the change of light pipe inclination angle. X-ray collimator with adjustable X-ray diameter 3, tiny sample tilting and rotating mechanism driven by stepping motor 4, manual adjuster for sample height and horizontal position 5, high-magnification and high-definition sample electron video microscope 6 , the CCD probe of this microscope is connected with a monitor with crosshairs to observe the position of the sample, the turntable system 7 of the sample stage adopts a high-precision worm gear drive system, and the drive system 8 of the detector adopts a harmonic gear motor or Ordinary geared motor.

The installation structure of the diffractometer is shown in Figure 1. The X-ray tube is fixed on the main board of the measuring instrument through a fixing device, and the drive system of the detector and the sample is also fixed on the main board of the measuring instrument. This ensures the firmness and stability of the overall mechanical structure. The X-ray detector adopts a small one-dimensional or two-dimensional array detector 9, and cooperates with the corresponding self-developed measurement software to obtain high measurement intensity. A perfect high-voltage generator safety circuit system is designed. When the lead glass door of the instrument is not closed, the high-voltage generator of the instrument cannot generate high voltage, which ensures the safety of the instrument.

Example

1. Take the tiny single crystal out of the sample box with a needle tip, observe it under a microscope and place it on a white plastic sample holder with a magnet base.

2. Transfer the sample holder together with the sample to the magnetic base of the XYZ sample stage 5, and roughly adjust the position of the sample so that it is close to the reticle on the monitor attached to the microscope. Then adjust the micrometer head in the XY direction so that the center of the sample coincides with the center of the crosshair.

3. Tilt the sample to 90 degrees and adjust the height of the sample so that the upper surface of the sample coincides with the horizontal line of the crosshair on the display.

4. Open the measurement software, click the start measurement button, the test program starts, automatically change the inclination and rotation of the sample, detect the diffraction intensity, find the diffraction peak, use a smaller step size near the diffraction peak to optimize the tilt and rotation of the sample, optimize After the end, the spectral line of the diffraction peak is automatically measured, and the position of the diffraction peak is calculated, and written into a specific measurement result file.

5. When the measurement is over, remove the sample and start preparing the next sample.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention and not to limit them. Although the embodiments of the present invention have been described in detail with reference to the above preferred embodiments, those of ordinary skill in the art should understand that they can Modifications or equivalent replacements to the technical solutions of the embodiments of the present invention should not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. A micro single crystal unit cell parameter measuring instrument, the instrument comprising: the X-ray detector comprises a measuring instrument main board, an X-ray tube fixing device, an X-ray collimator capable of adjusting the output size of X-rays, a sample video microscope, a sample table and an X-ray detector;

the X-ray tube and the X-ray collimator are fixed on a main board of the measuring instrument through the fixing device, and after the output size of X-rays emitted by the X-ray tube is regulated by the X-ray collimator, the X-rays irradiate a micro single crystal sample on the sample table and then are reflected to the X-ray detector by the crystal sample; the sample stage and the X-ray detector are also mounted on the main board of the measuring instrument.

2. The unit cell parameter measurement apparatus of claim 1, wherein the X-ray tube fixture comprises a three-dimensional position adjustment device, a manual slip table, and an X-ray tube tilting device.

3. The unit cell parameter measurement apparatus of claim 2, wherein the sample stage comprises: tilting and rotating means for the micro single crystal sample, and a regulator for the height and horizontal position of the sample;

the tilting and rotating mechanism is driven by a stepping motor;

the sample height and horizontal position regulator is a manual adjustment structure capable of providing height elevation and position movement in both the longitudinal and transverse directions on a horizontal plane.

4. A unit cell parameter measuring apparatus according to claim 3, wherein the tilting and rotating mechanism is constructed using a turntable of high precision worm gears.

5. The unit cell parameter measurement apparatus of claim 1, wherein the X-ray detector employs a small one-dimensional or two-dimensional array detector;

the X-ray detector is fixed on the driving device, the driving device is arranged on the main board of the measuring instrument, and a preset angle is formed between the connecting line from the surface of the X-ray detector to the sample table and the X-ray emitted by the X-ray tube; a predetermined distance is reserved between the surface of the X-ray detector and the sample table; the driving device can drive the X-ray detector to adjust in a preset area range so as to change the included angle between the normal line and the axis of the surface of the X-ray detector and the X-ray emitted by the X-ray tube.

6. A unit cell parameter measuring apparatus according to claim 5, wherein the driving means is driven by a harmonic reduction motor or a common reduction motor.

7. The unit cell parameter measurement apparatus of claim 5, further comprising a sample video microscope coupled to a display with cross-hairs, the sample video microscope and the display for viewing the sample.

8. A method of operating a micro single crystal unit cell parameter measurement apparatus as set forth in any one of claims 1-7, the method comprising the steps of:

step 1, taking out a tiny monocrystal from a sample box by using a needle point, checking the tiny monocrystal under an observation microscope, and transferring the tiny monocrystal to a plastic sample holder with a magnet base;

step 2, transferring the sample support carrying the tiny single crystals to a magnetic base of a sample stage, roughly adjusting the positions of the tiny single crystals so that the tiny single crystals are positioned near a cross line of a display, and finely adjusting the centers of the tiny single crystals to coincide with the center of the cross line;

step 3, tilting the micro single crystal to 90 degrees, and adjusting the height of the micro single crystal to enable the upper surface of the micro single crystal to coincide with the horizontal transverse line of the cross line on the display screen;

step 4, opening the measuring software, clicking a measurement starting key, and starting a test program;

and 5, taking down the sample holder after the measurement is finished.

9. The method of operation of claim 8, wherein step 2 comprises: the manual adjustment structure of the sample stage is used to move the small single crystals at positions in both the longitudinal and transverse directions in the height and horizontal planes.

10. The method of operation of claim 9, the test procedure of step 5 comprising:

step 5.1, automatically changing the inclination angle and rotation of the tiny single crystals according to a preset step length, and detecting the diffraction intensity of X rays on the tiny single crystals;

step 5.2, repeatedly executing inclination and rotation of the micro single crystal by using a step length smaller than a preset step length near the diffraction peak after finding the diffraction peak, and measuring spectral lines of the diffraction peak;

and 5.3, calculating the accurate position of the diffraction peak of the micro single crystal, and writing a specified measurement result file.