CN1734229A - Micro size measuring instrument - Google Patents

Abstract

To accurately and simultaneously measure a plurality of patterns even when an object to be measured is arranged at an angle or patterns on the object to be measured is very slightly displaced from a specified position. A plurality of detecting parts 26 and 28 are arranged in such a way as to asynchronously move along an X-axis frame 18. The detecting parts 26 and 28 as a whole are arranged in such a way as to move along a Y-axis frame 20. Each of the detecting parts 26 and 28 is arranged in such a way as to asynchronously move along a Y-axis direction within a prescribed range. When a flat panel 46 is arranged in such a way as not to be in parallel with X-Y coordinate axes and arranged at an angle to the Y-axis or when patterns of a liquid crystal monitor 48 are displaced from registered patterns, the detecting parts 26 and 28 are independently moved along the Y-axis direction to correct positional displacements according to the inclination and pattern displacements of the flat panel 46 to accurately and simultaneously measure a plurality of patterns on the liquid crystal monitor 48 and shorten tact time.

Description

Micro size measuring instrument

technical field

The present invention relates to a micro-size measuring instrument, which takes an object to be measured as an object, takes an image, processes the image obtained by the image, and measures the micro size of the object to be measured.

Background technique

As a device for measuring the minute size of the object to be measured, for example, the space facing each liquid crystal monitor on a flat panel formed of liquid crystal monitors is used as a moving space, the detector is moved in three-dimensional directions, and the detector measures the size of each liquid crystal monitor. The machine for the line width of the formed graphics, etc. Such a micro dimension measuring instrument is equipped with a camera etc. on the detector, and the camera takes an image of each liquid crystal monitor, and by processing the image obtained by the camera, it is possible to measure the line width of the pattern formed on each liquid crystal monitor.

However, in the configuration in which a single detector is used to measure a plurality of liquid crystal monitors, it takes time to move the detector to the position of each liquid crystal monitor, and the measurement time for a flat panel cannot be shortened. In order to shorten the measurement time (measurement time) of a panel formed by a plurality of liquid crystal monitors, it is possible to adopt a configuration in which a plurality of detectors are prepared and each detector is moved to each liquid crystal monitor at the same time.

For example, arrange the flat plate in parallel with the X-Y coordinates (mechanical coordinates) of the measuring instrument, arrange multiple detectors that can slide freely on the X-axis frame that constitutes the X-axis, and configure multiple detectors through the Y-axis drive unit. The X-axis frame of the detector moves along the Y-axis direction, so that each detector can be moved to the position of each liquid crystal monitor.

However, in a structure in which a plurality of detectors are slidably arranged on an X-axis frame and the X-axis frame on which a plurality of detectors are arranged is moved in the Y-axis direction, each detector can be individually moved in the X-axis direction. , but it cannot move individually in the direction of the Y axis. Therefore, when the flat panel is not arranged parallel to the X-Y coordinates of the measuring instrument, for example, when it is arranged in an inclined state relative to the Y axis, after moving each detector along the Y axis direction at the same time, even if each detector moves individually along the X axis direction, it can be One detector is positioned at the specified measurement position, but other detectors cannot be positioned at the specified measurement position, and multiple graphics cannot be measured at the same time with each detector.

In addition, even if the X-Y coordinates of the flat plate are arranged in parallel, and the figure on a certain measurement position deviates slightly from the registered figure, even if each detector moves to the measurement position for measurement, the exact size of the figure cannot be measured. That is, when the pattern is slightly shifted from the registered pattern, multiple patterns cannot be accurately measured unless the position of each detector is corrected according to the shift.

Contents of the invention

The present invention is proposed in view of the above-mentioned existing problems, and its object is to provide a micro-sized measuring instrument, even if the measured object is not arranged parallel to the mechanical coordinates of the measuring instrument, the measured object is arranged obliquely, or the measured object It is also possible to measure multiple graphics accurately and simultaneously.

In order to achieve the above object, the micro-size measuring instrument related to technical solution 1 has: a plurality of detection parts that respectively capture a plurality of patterns on the object to be measured; an image processing part that processes the images captured by the plurality of detection parts , and calculate the tiny size of the above-mentioned plurality of graphics; and the drive unit uses at least the space facing the measured area of the above-mentioned measured object as a movement space, and makes the above-mentioned plurality of detection units move along the three-dimensional direction in the above-mentioned movement space Wherein, the structure of the driving unit includes: a main driving unit that moves the plurality of detection units as a whole along the one-dimensional direction in the above-mentioned three dimensions; Auxiliary drive unit for synchronous movement.

(Function) Each detection unit images a plurality of graphics on the object to be measured, and processes the captured image. When measuring the microscopic size related to each graphics, since the plurality of detection units are aligned in a one-dimensional direction as a whole, For example, move along the Y-axis direction, and make multiple detection parts at least move along the two-dimensional direction, such as along the X-axis direction and the Y-axis direction synchronously, so even if the measured object is relative to the mechanical coordinates of the measuring instrument, such as relative to the X-Y coordinates The marks are not arranged in parallel, but the object to be measured is arranged obliquely to the Y axis, or the position of the pattern on the object to be measured is slightly shifted from the specified position, and each detection part can be moved asynchronously at least along the two-dimensional direction, By fine-tuning each detection unit, multiple patterns can be measured accurately and simultaneously, which shortens the measurement time. In addition, multiple measurement points can be measured at the same time, and the measurement time can be shortened.

In claim 2, in the micro-size measuring instrument according to claim 1, the auxiliary driving unit includes: taking the X, Y, and Z directions as three-dimensional directions, and moving the plurality of detection units asynchronously along the X direction, respectively. A plurality of auxiliary drive units for the X direction; a plurality of auxiliary drive units for the Y direction that move the plurality of detection units asynchronously along the Y direction; and a plurality of auxiliary drive units that move the plurality of detection units asynchronously along the Z direction. An auxiliary drive unit for the Z direction.

(Function) After moving the plurality of detection units as a whole to the vicinity of each figure, by asynchronously moving each detection unit in the X direction, Y direction or Z direction, the position of each detection unit can be individually fine-tuned.

In claim 3, in the micro dimension measuring instrument according to claim 2, at least one of the plurality of auxiliary drive units for the X direction, the plurality of auxiliary drive units for the Y direction, or the plurality of auxiliary drive units for the Z direction is composed of A linear motor is configured including a magnet arranged along a designated direction among X, Y, or Z directions, and a coil arranged on each detection unit.

(Function) By constituting the auxiliary drive unit with a linear motor having a magnet and a coil, even if a plurality of detection units are arranged on the same axis, each detection unit can be moved asynchronously, and the structure can be simplified.

The present invention has the following effects.

As can be seen from the above description, according to the micro-size measuring instrument according to Claim 1, the measurement time can be shortened.

According to claim 2, the positions of the detection parts can be finely adjusted individually.

According to technical solution 3, the simplification of a structure can be realized.

Description of drawings

FIG. 1 is a perspective view showing a micro dimension measuring instrument according to an embodiment of the present invention.

Fig. 2 is a perspective view showing a micro-size measuring instrument according to an embodiment of the present invention, and is a perspective view showing a state in which a detection unit is omitted,

Fig. 3 is a plan view of the panel.

Fig. 4 is an enlarged plan view of a measurement pattern.

Fig. 5 is a structural diagram of a full-closed-loop control system.

Fig. 6 is a plan view showing a state when the plate is tilted.

Detailed ways

Embodiments of the present invention will be described below. FIG. 1 is a perspective view showing a micro dimension measuring instrument according to an embodiment of the present invention, and FIG. 2 is a perspective view illustrating the micro dimension measuring instrument according to an embodiment of the present invention, and is a perspective view showing a state in which a detection unit is omitted. 3 is a plan view of the plate, FIG. 4 is an enlarged plan view of a measurement pattern, FIG. 5 is a configuration diagram of a fully closed loop control system, and FIG. 6 is a plan view showing the state of the plate when it is tilted.

In these figures, the micro-size measuring instrument 16, as a three-dimensional measuring instrument, has a structure comprising: an X-axis frame 18 constituting the X-axis of the X-Y coordinate (mechanical coordinate); a pair of Y-axis frames 20 constituting the Y-axis Base platform 22; Measuring table 24 fixed on base platform 22; A plurality of detection parts 26, 28 that can be configured to move asynchronously on the X-axis frame 18; For making each detection part 26, 28 can be along X An X-axis drive unit 30 that moves in the axial direction; an X-axis drive unit 32 that enables each detection unit 26, 28 to move in the Y-axis direction; a Z-axis drive unit that enables each detection unit 26, 28 to move in the Z-axis direction 34; a personal computer (hereinafter referred to as PC) 36 for calculating the driving of each driving unit; a display device 38 for displaying the processing results of the PC 36; a keyboard 40 for inputting various information to the PC 36; and indicating the driving direction of each driving unit etc. control box 42 etc.

Slide parts (not shown) are formed at both axial ends of the X-axis frame 18 , and each slide part is slidable along the Y-axis frame 20 . The X-axis frame 18 can move in the Y-axis direction by the drive of the Y-axis drive unit 32. The Y-axis drive unit 32 is composed of a linear motor having a plurality of magnets 32a for the Y-axis linear motor and coils 32b for the Y-axis linear motor. . When the coil 32b of the linear motor is energized, and the amount and direction of energization to the coil 32b are controlled by the PC 36, the X-axis frame 18 moves along the Y-axis direction (the Y-axis frame 20). That is, by driving the Y-axis drive unit 32 , the entire detection units 26 and 28 can move in the Y-axis direction along with the movement of the X-axis frame 18 . At this time, the Y-axis drive unit 32 constitutes a main drive unit that moves the detection units 26 and 28 in the Y-axis direction.

In addition, an X-axis drive unit 30 for asynchronously moving the detection units 26 and 28 in the X-axis direction (the X-axis frame 18 ) is disposed on the X-axis frame 18 . The structure of the X-axis drive unit 30 includes: a plurality of X-axis linear motor magnets 30 a arranged along the X-axis frame 18 ; and X-axis linear motor coils 30 b mounted on the detection units 26 and 28 . By controlling the energization amount and energization direction to each coil 30b by PC36, each detection part 26, 28 can be moved asynchronously (independently) along the X-axis direction. At this time, the X-axis drive unit 30 constituted by a linear motor constitutes an auxiliary drive unit for the X direction that asynchronously moves the detection units 26 and 28 in the X-axis direction.

The base 22 that fixes the frame 18 for the X-axis and the frame 20 for the Y-axis is supported by a plurality of frames 44 fixed on the base. Coordinates of the measuring table 24 . Both ends of the measurement table 24 are supported by a table frame 24a, and a flat plate 46 as an object to be measured is mounted on the upper surface of the measurement table 24 as shown in FIG. 3 . A plurality of liquid crystal monitors 48 to be measured are formed on a flat plate 46 formed in a substantially rectangular shape. Alignment marks M1 and M2 are formed on the upper and lower parts of the left end side of the flat plate 46 . Measurement points (management points) P1 to P4 are set on each liquid crystal monitor 48, and as shown in FIG. 4, patterns PT1, PT2, . . . constituting a driving circuit and the like are formed.

At least the space facing the liquid crystal monitor 48 arranged in the area to be measured of the flat panel 46 is used as a moving area, and the detection parts 26 and 28 are movable along three-dimensional directions in the moving area, and each detection part 26 and 28 has a detection part Subject 50. In the lens barrel 52 of each detection part main body 50, the liquid crystal monitor 48 on the flat panel 46 is taken as an object, and an objective lens 54 and a CCD camera 56 are installed as an imaging device for taking pictures of images on the liquid crystal monitor 48 . Objective lens 54, CCD camera 56 have the function of electron microscope, the figure on liquid crystal monitor 48 is enlarged and photographed, and the signal of the relevant image of photographing is transmitted to PC36 by cable (not shown). In addition, each lens barrel 52 is connected to a Z-axis servo motor 58 as a Z-direction auxiliary drive unit for focusing the imaging device so that the imaging device can move along the Z-axis direction according to a control signal output from the PC 36 . At this time, one Z-axis servomotor 58 functions as a Z1-axis servomotor, another Z-axis servomotor 58 functions as a Z2-axis servomotor, and the objective lens 54 and the CCD camera 56 in a lens barrel 52 can reciprocate along the Z1 axis Moving, the objective lens 54 and the CCD camera 56 in the other lens barrel 52 can reciprocate along the Z2 axis.

On the main body 50 of each detection part, a Y-axis servo motor 60 as an auxiliary drive part for the Y direction is also provided, so as to respond to the control signal output by the PC36, and make each detection part 26, 28 move asynchronously along the Y-axis direction. . One Y-axis servomotor 60 serves as a Y1S servomotor to reciprocate one detection unit 26 along an auxiliary Y-axis (Y1S-axis) parallel to the Y-axis frame 20 . The other Y-axis servo motor 60 serves as a Y2S servo motor and can reciprocate the other detection unit 28 along an auxiliary Y-axis (Y2S-axis) parallel to the Y-axis frame 20 .

Here, in order to perform high-precision positioning in the X-axis direction of each detection unit 26, 28, a full closed loop (Full Closed Loop) control system is formed on the X-axis driving unit 30 as shown in FIG. 5 .

Specifically, a plurality of magnets 30a are arranged parallel to the X-axis (X-axis frame 18), and linear guides 62 and glass dials (glass scales) for guiding the movement of each detection unit main body 50 are arranged in parallel with the X-axis. 64. In addition, position sensors (linear sensors) 66 are mounted on each detection unit main body 50 , and each position sensor 66 detects the scale of the glass dial 64 and outputs a detection signal to a proportional counter (skelcounter) 68 . The proportional counter 68 responds to the detection signal of the position sensor 66 , counts the number of graduations on the glass scale (linear scale) 64 , and outputs the count value to the monitor driver 70 . The monitor driver 70 outputs the position information of each detection part main body 50 to the linear motor and the PC36, and the PC36 can control the amount and direction of energization to the coil 36b on each detection part main body 50 according to the position information, and can control each detection part with high precision. Positioning of the main body 50 in the X-axis direction.

Also, in the Y-axis drive unit 32 , like the X-axis drive unit 30 , a full-closed loop control system is configured by using the position sensor 66 a and the like, and high-precision positioning can be performed in the Y-axis direction of each detection unit 26 , 28 .

When using the micro-size measuring instrument 16 according to the above-mentioned structure to measure the graphic of the liquid crystal monitor 48 formed on the flat panel 46, as shown in FIG. position, for example, the detection unit 26 is arranged at a position corresponding to the positioning marks M1 and M2, the X-axis frame 18 is moved along the Y-axis direction, and the positioning marks M1 and M2 are sequentially photographed by the detection unit 26, and the imaging is processed by the PC36 , and judge whether the flat plate 46 is arranged in parallel to the X-Y coordinates. When it is judged that the flat plate 46 is arranged parallel to the X-Y coordinates, the X-axis frame 18 is moved along the Y-axis direction in a state where the detection parts 26 and 28 are respectively arranged at designated positions of the X-axis frame 18, and first positioned on the flat plate 46. On the liquid crystal monitor 48 that is arranged on the left upper part. At this time, the detection units 26 and 28 are respectively moved along the X-axis frame 18 to position the detection units 26 and 28 at positions corresponding to the measurement points P1 and P2. Further, by driving the Z-axis servo motor 58 , each detection unit 26 , 28 is moved in the Z-axis direction to perform focusing. When performing this focusing, each measurement point P1, P2 is imaged by the CCD camera 56, and the imaged image is processed by PC36. At this time, pattern matching (pattern matching) is performed on the measured pattern and the pre-registered registered pattern, and it is judged whether there is an offset between the two. When there is no misalignment, the images taken by the detection units 26 and 28 are processed, and as shown in FIG. 4 , the line widths of the patterns PT1 and PT2 at the measurement points P1 and P2 are measured. At this time, the PC 36 functions as an image processing unit to process the image captured by the CCD camera 56 to calculate the minute size of a plurality of graphics. The PC36 performs these processes on the measurement points P1, P2, P3, and P4 on each liquid crystal monitor 48. When measuring the measurement points P1 to P4, the detection parts 26 and 28 are used to simultaneously measure the measurement points P1, P2 and measurement points P1 and P2 respectively. The small size of the graphics PT1 and PT2 on P3 and P4 can shorten the measurement time.

When there is a slight deviation between the two in pattern matching, the detector 24 or 26 that detects the deviation in the detection part 26, 28 can be moved in the direction of the Y axis (auxiliary Y axis) by driving the Y axis servo motor. Move a small amount to correct the offset.

On the other hand, as shown in Figure 6, by the measurement of the positioning marks M1 and M2 on the flat board 46, it is judged that the X-Y coordinates of the flat board 46 are not parallel to the X-Y coordinates of the micro-size measuring instrument 16, but are arranged on the Y axis (the Y axis is used for the Y axis). When the frame 20) is arranged in an inclined state, in order to correct the inclination to the Y axis, the Y axis servo motor 60 is driven according to the inclination of the flat plate 46 to the Y axis direction to correct the deviation of each detection part 26, 28 in the Y axis direction. At this time, since the detection unit 28 is farther from the origin of the X-Y coordinates than the detection unit 26 , it is positioned at a position slightly moved in the Y-axis direction than the detection unit 26 . For convenience, the origin of the X-Y coordinates is set on the lower left side of Fig. 1, but it can also be the center of XY movement.

After correcting the offset of each detection part 26, 28, each detection part 26, 28 is driven by a linear motor, moves along the Y-axis direction together with the X-axis frame 18, and is positioned at the measurement point P1, above P2. At this time, by driving the Z-axis servo motor 58, the detection unit 28 moves in the Z-axis direction to focus. When the detection points 26 and 28 are respectively moved in parallel along the X-axis, the origin of the detection parts 26 and 28 in the Y-axis direction is the center at which the detection parts move back and forth. If the detection parts 26, 28 are parallel on the X-axis, any position of movement can be used as the origin. Then, when each measurement point P1, P2 is imaged by the CCD56 of the detection part 26, 28, the imaged image is processed by the PC36, and pattern matching is performed on the detected pattern and the registered pattern. When it is judged by the pattern matching that there is a slight misalignment between the two, the detection unit 26 or the detection unit 28 that has detected the misalignment performs a process of correcting the misalignment. That is, the Y-axis servo motor 60 is driven to move the detection unit 26 or the detection unit 28 in the Y-axis (auxiliary Y-axis) direction based on the control signal for offset correction, thereby correcting the offset. At this time, coordinate transformation is performed from the machine coordinate system with the positioning marks M1 and M2 as references.

Then, the measurement points P1 and P2 are imaged again by the detection units 26 and 28, and the images obtained by the imaging are processed by the PC 36, and the micro line width (CD) and Measurement of coincidence (0L). That is, a process of measuring the width and size of a micro-sized figure at a precision level is performed.

After the measurement is completed, a process of returning the offset correction amount calculated by pattern matching to the original value is performed, and the process moves to the process of measuring the next measurement points P3 and P4. Also at the next measurement points P3 and P4, the processing of correcting the correction amount of each detection unit 26 and 28 in the Y-axis direction is performed according to the inclination of the flat plate 46, and the same processing is repeated.

In this way, according to this embodiment, even if the flat panel 46 is tilted to the Y axis, or the graphic on the liquid crystal monitor 48 deviates slightly from the registered graphic, the detection parts 26 and 28 can be asynchronously moved along by the drive of each servo motor 60 . Since it moves in the direction of the Y-axis (Y-axis for auxiliary use), multiple figures can be measured accurately at the same time, and the measurement time can be shortened.

In this embodiment, since the detection parts 26 and 28 can be moved asynchronously (independently) along the Z axis by the drive of the Z axis servo motor, it is possible to accurately focus and measure multiple patterns more accurately. Reduce measurement time.

In addition, since the linear motor is used for the X-axis driving part 30, the detecting parts 26 and 28 can be moved asynchronously in a wide range along the X-axis direction, and the structure can be simplified.

Claims (3)

1. A micro-size measuring instrument, characterized in that it has: A plurality of detection units that respectively take pictures of a plurality of patterns on the object to be measured; an image processing unit, which processes the images captured by the plurality of detection units, and calculates the tiny sizes of the plurality of graphics; and The drive unit uses at least a space facing the measured region of the measured object as a movement space, and moves the plurality of detection units in three-dimensional directions in the movement space, The structure of the drive unit includes: a main drive unit that moves the plurality of detection units as a whole along one of the three-dimensional directions; and moves the plurality of detection units asynchronously along at least two-dimensional directions of the three dimensions. Auxiliary drive unit. 2. The micro dimension measuring instrument according to claim 1, characterized in that: The above-mentioned auxiliary driving unit has: taking X, Y, Z directions as three-dimensional directions, and a plurality of auxiliary driving units for the X direction that move the plurality of detection units asynchronously along the X direction; a plurality of auxiliary drive units for the Y direction that move asynchronously in the Y direction; and a plurality of auxiliary drive units for the Z direction that move the plurality of detection units asynchronously along the Z direction. 3. The micro dimension measuring instrument according to claim 2, characterized in that: At least one of the plurality of auxiliary drive units for the X direction, the plurality of auxiliary drive units for the Y direction, or the plurality of auxiliary drive units for the Z direction is constituted by a linear motor having: A magnet arranged in a direction specified in the direction; and a coil arranged on each of the above-mentioned detection parts.

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