KR101350570B1 - Apparatus and method for obtaining stereographic - Google Patents

Abstract

The present invention relates to an apparatus and a method for obtaining a stereoscopic image. The apparatus comprises: a specimen moving unit which fixates a specimen in the upper part thereof; a fixating arm whose lower part is fixated to the side surface of the specimen moving unit and whose upper part is partly bent to both sides of the upper part of the specimen moving unit; and a probe moving unit which is combined with the upper part of the fixating arm in order to be able to move in a z-axis direction and fixates a probe so that the probe can perform translational motion in x-, y-, and z-axis directions and rotary motion on the x-axis as relative motion to the specimen moving unit. The probe for scanning the specimen can obtain a true three-dimensional image through unidirectional scanning by being formed to be able to perform 3-degree-of-freedom translational motion and rotary motion. Therefore, the apparatus can provide effects of raising a scanning speed and obtaining a perfect three-dimensional image.

Description

Apparatus and method for acquiring stereoscopic image {APPARATUS AND METHOD FOR OBTAINING STEREOGRAPHIC}

The present invention relates to an apparatus and method for obtaining a three-dimensional solid shape, and more particularly, to an apparatus and method for obtaining a three-dimensional shape capable of measuring a three-dimensional shape with an atomic force microscope capable of measuring an image of a specimen in nanometer units. will be.

In general, true three-dimensional measurements including additional shape information such as sidewalls or undercuts are used to identify the characteristics of structures in various nanotechnology fields such as semiconductor, thin film technology, molecular biology, and cytology. Although necessary, at present, since only two-dimensional photograph information is measured, perfect three-dimensional shape information is difficult to obtain.

FIG. 1 is a schematic diagram of a part of an integrated circuit processed by an exposure process, and the performance of the integrated circuit includes line edge roughness (LER), sidewall roughness (SR), and base width (BW). In the evaluation of the manufacturing performance of laminated planar CMOS or thin film coating, quality and performance are evaluated by measuring the thickness of the thin film through sidewall measurement.

2 is a photograph of an immunoassay sensor composed of glass and gold to improve sensitivity.

Such sensors are becoming increasingly complex in shape and composition of nanostructures. As such, the need for true three-dimensional measurement is increasing to measure the performance and properties of nanostructures.

However, conventional scanning electron microscope (SEM) and transmission electron microscope (TEM), which are mainly used for measuring sidewalls, can measure only conductive materials, long specimen preparation time, specimen failure during preparation, limited three-dimensional profile measurement, There was a problem such as a decrease in resolution for dissimilar material structures.

In order to solve the problems of SEM and TEM, it is replaced by measurement using atomic force microscope. In particular, it is essential to use atomic force microscope to examine the mechanical properties of nanostructures.

3 is an explanatory diagram for explaining a method in a three-dimensional measurement by a conventional atomic force microscope.

Referring to FIG. 3, in the conventional three-dimensional structure measurement using an atomic force microscope, the tip of the probe is moved and scanned in the x-axis direction, and only the topography in the z-axis direction is measured. Information such as undercut has a limitation that is expressed by a simple inclined plane, and researches are being conducted to improve the scanning method and the method of modifying the tip shape of the probe to overcome this limitation.

FIG. 4 is a photograph of a cantilever tip made by the German team “Physikalish-Technische Bund-esanstalt”.

The conventional cantilever tip has a form in which a cantilever extending vertically to an existing cantilever is additionally attached to scan a sidewall. The conventional cantilever tip of such a configuration can measure sidewalls, but there is a limitation in the horizontal plane measurement. In order to compensate for this, the cantilever tip has been proposed to add a horizontal cantilever, but there is an interference problem between the specimen and the added cantilever. For the cantilever processing method, there is no satisfactory solution.

5 is an explanatory diagram for explaining a scanning method proposed by the Japanese "AIST" research team.

Referring to FIG. 5, the left side is a conventional “step-in mode” scan method, and in this scan method, a “tilt-step-in mode” in which a probe tip is scanned in order to solve difficulties such as measurement of sidewalls. "The way was proposed.

However, it has low performance in terms of resolution and scan speed, and can only measure side walls on one side because the tilt angle is fixed.

In Korean Patent Laid-Open Publication No. 10-2010-0112207, a scanning probe microscope having a structure capable of measuring both sides of a sidewall and a method of controlling the same have been proposed, but in order to measure a three-dimensional shape, the same point is bi-directionally (left / right) two or more times. There is a drawback to scanning, which is necessary as an additional mechanism for stable rotation, which causes a problem that the system is bulky.

As described above, the sidewall measurement method using the atomic force microscope still needs to be improved in terms of structure complexity, cost, measurement speed, and true three-dimensional measurement.

The technical problem to be solved by the present invention in view of the above problems is to provide a three-dimensional acquisition device and method that can measure not only the height of the specimen but also the side surface of the specimen.

Another object of the present invention is to provide an apparatus and method for acquiring a true three-dimensional shape, but shortening a scanning time.

In the present invention, the three-dimensional acquisition device for solving the above problems, the specimen moving portion for fixing the specimen on the upper side, and the lower end is fixed to the side surface of the specimen moving portion, the upper portion is to the upper center side of the specimen moving portion The fixed arm is bent and coupled to the upper end of the fixed arm so as to be movable in the z-axis direction, and the probe is fixed, wherein the probe is moved relative to the specimen moving part in the x-axis, y-axis and z-axis directions. The translational movement of the probe includes a probe moving unit capable of rotating around the x axis.

In addition, the method of obtaining a three-dimensional shape of the present invention is a detection method for detecting a three-dimensional structure of the specimen by a probe in contact with the specimen in the initial position, the probe is relative translational movement in the x-axis, y-axis and z-axis direction with the specimen In addition, by repeating the rotational movement around the x-axis, displacement in the y-axis direction, and scanning in the x-axis direction, the process moves along the z-axis according to the height of the specimen and the x-axis according to the inclination of the specimen It is characterized by rotating to the center.

The apparatus and method for acquiring a three-dimensional shape of the present invention is configured to enable three degrees of freedom translation and rotational movement of a probe for scanning a specimen, thereby obtaining a true three-dimensional shape by scanning in one direction, thereby increasing the scanning speed. In addition to the shortening effect, there is an effect of obtaining a perfect three-dimensional shape.

1 is a schematic diagram of a part of an integrated circuit processed by an exposure process.
2 is a photograph of a sensor for immunoassay.
3 is an explanatory diagram for explaining a method in a three-dimensional measurement by a conventional atomic force microscope.
FIG. 4 is a photograph of a cantilever tip made by the German team “Physikalish-Technische Bund-esanstalt”.
5 is an explanatory diagram for explaining a scanning method proposed by the Japanese "AIST" research team.
6 is a perspective view of a three-dimensional shape obtaining apparatus according to a preferred embodiment of the present invention.
7 is a side configuration diagram of FIG. 6.
8 is an explanatory diagram for explaining a process of scanning a specimen with the present invention.
9 to 11 are schematic structural diagrams of another embodiment of the present invention.
12 is a hardware configuration diagram for adjusting the x-axis rotation angle and the y-axis tilt angle of the probe.

Hereinafter, an apparatus and method for obtaining a 3D image according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

6 is a perspective view of a three-dimensional acquisition apparatus according to a preferred embodiment of the present invention, Figure 7 is a side configuration diagram of FIG.

Referring to FIGS. 6 and 7, the apparatus for acquiring a three-dimensional shape according to an exemplary embodiment of the present invention includes a specimen moving part 300 which fixes a specimen which is an imaging object having a three-dimensional shape and moves the specimen along an xy axis. And a fixed arm 100 fixed to the side of the specimen moving part 300 and extending to an upper side of the specimen, and coupled to one side of the fixed arm 100 to move the probe in the z-axis direction. By rotating the probe around the x-axis to adjust the rotation angle, the specimen moving part 300 and the probe moving part 200 to obtain a three-dimensional shape of the specimen through the relative movement.

The specimen moving unit 300 is coupled to the side of the fixed arm 100, providing a movement in the xyz axis, the first scanner 310 is possible to adjust the approximate position for setting the initial position of the specimen, The first scanner 310 is movable along three axes of xyz axis, and is provided on the upper part of the second scanner 320 and the second scanner 320 to provide a precise movement in the xy two axis direction. The second scanner 320 is movable in a plane, and comprises a specimen stand 330 is fixed to the specimen on the top.

The probe moving unit 200 is coupled to the z-axis moving unit 210 so as to be movable in the z-axis direction on the upper end of the fixed arm 100, and is coupled to the z-axis moving unit 210 to the center of the x-axis The driving unit (not shown) to rotate the rotation support unit 220 is provided integrally with a rotation angle sensor (not shown) for measuring the rotation angle, and rotates around the x-axis by the rotation support unit 220 An x-axis rotating part 230, a probe support 250 for fixing a probe (not shown) on the bottom surface side of the x-axis rotating part 230, and a sensor part 240 for detecting twist and bending of the probe. It is configured to include.

Hereinafter, the configuration and operation of the apparatus and method for obtaining a three-dimensional shape of the present invention configured as described above will be described in more detail.

First, the specimen moving part 300 has a flat plate structure at a lower portion thereof, and a first scanner 310 capable of moving the second scanner 320 up, down, left and right is provided. The degree of movement of the first scanner 310 is low in resolution, and rough movement in the x-axis and y-axis directions is possible, but the movement distance is relatively long.

The lower end of the fixed arm 100 is fixedly coupled to the side of the first scanner 310.

The fixed arm 100 has a predetermined height upward, the upper side is bent toward the upper center side of the first scanner 310, the probe moving portion 200 is at the end of the bent surface of the z-axis direction It is coupled to move up and down.

 The second scanner 320, which is roughly horizontally and vertically moved by the first scanner 310, provides a movement for moving the specimen table 330 located above the x and y axes. The movement provided by the second scanner 320 enables more precise movement with respect to the movement provided by the first scanner 310, and after the initial position is determined by the first scanner 310, a second movement is performed. The probe 320 may be scanned with a probe while moving the specimen stage 330 precisely.

At this time, the displacement of the specimen stage 330 given by the second scanner 320 is set smaller than the displacement of the second scanner 320 given by the first scanner 310.

The probe moving part 200 coupled to the upper end of the fixed arm 100 to be movable up and down along the z-axis provides a scanning movement independent of the specimen moving part 300.

As described above, the probe moving part 200 is provided with a z-axis moving part 210 that can move up and down with respect to the fixed arm 100 precisely, and the x-axis rotating part ( 230 and the rotation support portion 220 that can rotate the x-axis rotating portion 230 at a predetermined angle about the x-axis can be moved up and down, the probe support 250 according to the step of the specimen on the specimen table 330 Probe (not shown) fixed to the can be moved up and down.

Although not shown in the drawings, the rotation support unit 220 is provided with a driving unit which is a motor or a cylinder, and a rotation angle sensor capable of measuring the rotation angle is also provided integrally.

The front support side of the z-axis moving unit 210 is provided with a rotation support unit 220 is able to rotate the x-axis rotation unit 230 provided on the bottom of the probe support 250.

At this time, the rotation angle of the x-axis rotation unit 230 is the same as the rotation angle of the probe fixed to the probe support 250, the degree of twist and bending of the probe fixed to the probe support 250 is the sensor unit 240 The angle can be controlled by comparing with the set value sensed by.

At this time, the x-axis rotation unit 230, the probe support 250, the sensor unit 240 is rotated about the x-axis, the rotation center at this time is preferably the end of the probe. This is because the most easy calculation can be made when considering the degree of twist and bending of the probe to be detected in the three-dimensional shape of the specimen to be measured.

In addition, the probe has a torsion, which is a rotation about the x axis, and a bending about the y axis occurs in the y-axis scanning process. This is due to the surface shape of the specimen, the torsion angle around the x-axis is the z-axis moving unit 210 for controlling the height of the z-axis direction and the movement of the second scanner 320 to enable the scan in the y-axis direction ) Can be adjusted by controlling.

8 is an explanatory diagram for explaining a process of photographing a specimen using the three-dimensional shape obtaining apparatus according to the preferred embodiment of the present invention configured as described above.

Referring to FIG. 8, first, the specimen 400 is fixed on the specimen stage 330, and then the specimen 400 is positioned at an initial position using the first scanner 310.

At this time, the initial position of the specimen 400 includes all of the positions of the x-axis, y-axis, and z-axis. The rough position is adjusted by adjusting the first scanner 310 having a large displacement. The second scanner 320 may be used.

After the initial position is set, the probe 260 coupled to the probe support 250 is brought into contact with the specimen 400 at the A position. In this contact state, the second scanner 320 moves in the y-axis direction to complete the scan of the specimen 400 from the A position to the F position.

In this case, the probe 260 may be twisted about the x-axis and bending about the y-axis according to the surface shape of the specimen 400. The degree of twisting and bending at this time is detected by the sensor unit 240.

Next, after scanning along the y-axis direction, the probe 260 moves from the position of F by a distance set in the x-axis direction, and then the second scanner 320 is moved backwards in the y-axis direction to The specimen 400 will be scanned from position to position A.

In this scanning process, the probe 260 generates a twist about the x-axis according to the shape of the specimen, a degree of bending about the y-axis is determined, and a difference from the set value is corrected. This happens continuously in every scanning process, the configuration of which will be described in more detail later.

As described above, the present invention can obtain a three-dimensional shape including both sidewall portions of the specimen 400 by one scanning in one direction.

9 is a schematic view of a three-dimensional shape obtaining apparatus according to an embodiment of the present invention described above, the specimen 400 is translated in the x-axis and y-axis, the probe 260 along the z-axis direction It is possible to move up and down, and to detect the three-dimensional shape of the specimen 400 by the probe 260 through a relative motion that rotates within a predetermined angle about the x-axis.

Similarly, FIG. 10 is an explanatory diagram schematically showing a three-dimensional shape obtaining apparatus according to another embodiment of the present invention, wherein the specimen 400 may rotate in a predetermined angle range about an x axis, and a probe ( 260 is an example of a translational motion along the z-axis, x-axis and y-axis.

In addition, in FIG. 11, the specimen 400 is fixed, and the probe 260 performs translational movement along the x, y, and z axes, and is configured to rotate around the x axis. Such a configuration example also shows that a complete three-dimensional shape can be obtained through one scanning as in the above-described embodiment.

That is, the present invention can be applied irrespective of the specific configuration of the structure if the specimen and the probe can be rotated about the x-axis as well as the translational movement in the x, y, z axis as a relative motion.

12 is an example of a configuration for adjusting the degree of twist about the x-axis and the bending angle about the y-axis of the probe in the above embodiments.

Referring to FIG. 12, the degree of twist around the x-axis and the degree of bending around the y-axis of the probe 260 are sensed by the sensor unit 240. In this case, the degree of bending about the y-axis may be interpreted as a value according to the positions of the y-axis and the z-axis. The detection result of the sensor unit 240 is calculated by the x-axis set torsion value, the y-axis set bend value and the first and second calculation units (510, 520), respectively, the difference is obtained, the controller 530 receiving the difference is The z-axis moving unit 210, the rotation support unit 220, and the second scanner 320 are controlled to control the degree of twist around the x-axis and the degree of bending around the y-axis of the probe 260. Therefore, the present invention can maintain the bending and torsion of the probe 260 at a set value.

The x-axis twisting degree and the y-axis bending degree sensed by the sensor unit 240, the detection result of the rotation angle sensor of the rotary support unit 220, and the displacement of the z-axis moving unit 210 are combined one time continuously. Through scanning, three-dimensional shape information of the specimen 400 may be obtained.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention will be.

100: fixed arm 200: probe moving part
210: z-axis moving part 220: rotation support
230: x-axis rotating part 240: sensor part
250: probe support 260: probe
300: specimen moving part 310: first scanner
320: second scanner 330: specimen stand
400: Psalm

Claims (12)

A specimen moving part fixing the specimen to the upper portion;
A fixed arm having a lower end fixed to the side surface of the specimen moving part and an upper portion bent toward an upper center side of the specimen moving part; And
Coupled to the upper end of the fixed arm so as to be movable in the z-axis direction and fixing the probe, wherein the probe is moved relative to the specimen moving part in the x-axis, y-axis, and z-axis directions; Three-dimensional shape acquisition device including a probe moving unit capable of rotating movement about the x-axis.
The method of claim 1,
The specimen moving part fixes the specimen,
The probe moving unit translates the probe along the x-axis, y-axis, and z-axis, and rotates around the x-axis.
The method of claim 1,
The specimen moving part rotates the specimen about the x axis,
And the probe moving unit translates the probe along an x-axis, a y-axis, and a z-axis.
The method of claim 1,
The specimen moving unit translates the specimen along the x and y axes,
And the probe moving unit translates the probe along the z axis and rotates the x axis about the x axis.
The method of claim 1,
The specimen moving part,
A first scanner coupled to the side of the fixed arm and providing movement in the x-axis, y-axis, and z-axis, the first scanner being capable of roughly adjusting the initial position of the specimen;
A second scanner moved along the x-axis, y-axis and z-axis by the first scanner and providing precise movement in the x- and y-axis directions; And
Located in the upper portion of the second scanner is a three-dimensional shape acquisition device that can be moved in a plane by the second scanner, the specimen is fixed to the upper specimen.
The method of claim 5,
The probe moving unit,
A z-axis moving unit coupled to an upper end of the fixed arm to be movable in a z-axis direction;
A rotation support unit coupled to the z-axis moving unit to transmit a rotational force about an x-axis and including a rotation angle sensor to detect a rotation angle;
An x-axis rotating unit rotating about an x-axis by the rotating support unit;
A probe support for fixing the probe on the bottom surface side of the x-axis rotating part; And
And a sensor unit for detecting a degree of twist about the x axis and a degree of bending about the y axis of the probe.
The method according to claim 6,
The bending degree of the probe is detected by the sensor unit, and the second scanner and the z-axis moving unit are controlled according to a result of calculating a difference between a bending setting value centering on the y axis, and the bending setting centering on the y axis. Keep the value,
The degree of twist around the x axis of the probe is detected by the sensor unit, and the rotation support unit is controlled according to a result of calculating a difference from the torsion setting value around the x axis so that the twist setting value around the x axis is determined. Three-dimensional shape acquisition device characterized in that to maintain.
The method according to claim 6,
The x-axis rotating unit, the probe support and the sensor unit rotated by the rotation support unit to rotate so that the end of the probe is the center of rotation.
In the detection method for detecting the three-dimensional structure of the specimen with a probe in contact with the specimen in the initial position,
The probe moves relative to the specimen in the x-axis, y-axis, and z-axis directions, and rotates about the x-axis.
After displacing in the x-axis direction, the process of scanning in the y-axis direction is repeated, but moving along the z-axis according to the height of the specimen and rotating around the x-axis according to the inclination of the specimen. Way.
10. The method of claim 9,
The specimen is in a fixed state,
And the probe is translated along the x axis, the y axis, and the z axis, and rotates about the x axis.
10. The method of claim 9,
The specimen is rotated about the x axis,
The probe is a three-dimensional shape acquisition method characterized in that the translational motion along the x-axis, y-axis, z-axis.
10. The method of claim 9,
The specimen is translated along the x and y axes,
The probe has a three-dimensional shape acquisition method characterized in that the translational movement along the z-axis and the rotational movement around the x-axis.

Images