KR101358287B1 - Calibration system for laser beam scanner - Google Patents

Abstract

The present invention relates to a calibration system of a laser beam scanning device, comprising: a laser light source unit for generating and outputting laser light; A scanner unit installed at a rear end of the laser light source unit and configured to adjust vertical and horizontal displacements of the laser light incident from the laser light source unit; An optical unit installed between the scanner unit and the substrate, the optical unit adjusting the laser light incident from the scanner unit to focus on the substrate; A calibration plate having a diffuse reflection portion formed at a plurality of points including a point corresponding to a pattern shape to be formed on the substrate and installed adjacent to the calibration plate, and detecting laser light incident and reflected by the diffuse reflection portion of the calibration plate; A calibration unit for extracting pattern correction data using a detection result of the light sensor unit; There is provided a calibration system of a laser beam scanning apparatus, the pattern information unit storing information on a pattern to be formed on the substrate and storing pattern correction data extracted through the calibration unit.

Description

Calibration system for laser beam scanning device {Calibration system for laser beam scanner}

The present invention relates to a calibration system of a laser beam scanning apparatus, and more particularly, after arranging a calibration plate on which a diffuse reflection unit is formed on a light-transmissive substrate, pattern correction is performed by sensing the intensity of the diffusely reflected light of the laser beam scanned by the calibration plate. The present invention relates to a calibration system of a laser beam scanning apparatus that extracts data and corrects distortion values of a laser beam using the extracted pattern correction data.

In general, an exposure apparatus for forming a pattern on a substrate is composed of a mask, an optical system, an adjusting stage, and an ultraviolet ray. In the pattern process, a photoresist film is formed on a film to form a pattern, and then a predetermined mask pattern is applied to the photoresist film. The photoresist film is positioned correspondingly, and the photoresist film is exposed according to a mask pattern using a UV lamp to develop and remove an exposed portion of the photoresist film, and then the exposed film is removed through the photoresist film pattern removed by development. Photolithography, which removes the photoresist film pattern and removes the photoresist film pattern to form a desired pattern on the film on the glass substrate. However, when glass patterning is performed by a photolithography method, the process is difficult, complicated, expensive to install equipment, and manufacturing time and cost increase.

In order to solve this problem, a method of forming a desired pattern by directly irradiating a laser onto a film has been developed and used, and various laser equipments are also used for marking processes such as semiconductors and LCDs.

1 is a schematic configuration diagram of a general laser beam scanning apparatus.

Referring to FIG. 1, the laser beam scanning apparatus includes a laser light source unit 10, a scanner unit 20, an optical unit 30, a pattern information unit 40, and a stage 90.

The laser light source unit 10 generates and irradiates laser light, and the scanner unit 20 reflects the laser light incident from the laser light source unit 10 and irradiates a desired pattern on the substrate. The optical unit 30 adjusts the laser light incident from the scanner unit 20 to focus on the substrate. The pattern information unit 40 provides pattern information about a pattern to be formed on the substrate 80 to a controller (not shown).

2 is a diagram illustrating a distortion phenomenon of a laser beam due to an operation of a scan unit of a laser beam scanning apparatus, FIG. 3A is a diagram illustrating a distorted shape of a laser beam due to a scan unit of a laser beam scanning apparatus, and FIG. 3B is a laser beam FIG. 3C is a diagram showing a distorted shape of a laser beam finally appearing on a substrate to be patterned.

In spite of these advantages, the laser marking apparatus or the laser pattern forming apparatus has different path lengths for reaching the target coordinates due to the characteristics of the scanning unit or the optical unit of the laser beam scanning apparatus, and the difference in the path lengths is accumulated, and thus the pattern pattern is intended. There is a problem that a different distorted pattern is formed.

Many methods have been proposed to compensate for this shortcoming. For example, a rule of the tested light is measured to determine the actual position of the scanned light, and the difference between the planned standard image and the actual measured image is used as a correction factor. Calibration devices using the method have been disclosed. In the conventional calibration apparatus, when the pattern work in the test step is completed, a pattern camera is photographed using a vision camera to measure the deviation by comparing the photographed pattern image with the ideal pattern image and reflecting the measured deviation amount. The correction was performed by correcting.

However, when using such a vision camera to install a separate vision camera, there is a problem that the cost increases and the installation space increases.

SUMMARY OF THE INVENTION The present invention has been made to overcome the above-mentioned conventional problems, and an object of the present invention is to provide a calibration system of a laser beam scanning apparatus capable of correcting pattern distortion more easily and at low cost.

Another object of the present invention is to provide a calibration system of a laser beam scanning device that improves precision and facilitates equipment design and maintenance.

According to an exemplary embodiment of the present invention, a laser light source unit for generating and outputting laser light; A scanner unit installed at a rear end of the laser light source unit and configured to adjust vertical and horizontal displacements of the laser light incident from the laser light source unit; An optical unit installed between the scanner unit and the substrate, the optical unit adjusting the laser light incident from the scanner unit to focus on the substrate; A calibration plate having a diffuse reflection portion formed at a plurality of points including a point corresponding to a pattern shape to be formed on the substrate and installed adjacent to the calibration plate, and detecting laser light incident and reflected by the diffuse reflection portion of the calibration plate; A calibration unit for extracting pattern correction data using a detection result of the light sensor unit; There is provided a calibration system of a laser beam scanning apparatus, the pattern information unit storing information on a pattern to be formed on the substrate and storing pattern correction data extracted through the calibration unit.

The scanner unit is installed at the rear end of the first galvano scanner and the first galvano scanner for adjusting displacement in the first axial direction of the laser light incident from the laser light source unit, and is incident from the first galvano scanner. And a second galvano scanner for adjusting displacement in the second axial direction of the laser light.

The calibration unit includes a light-transmitting substrate and a plurality of diffuse reflection portions formed on the light-transmissive substrate, wherein the plurality of diffuse reflection portions are calibration plates formed at a plurality of points to include a point corresponding to a pattern shape to be actually formed on the substrate; And an optical sensor unit installed at a side of the calibration plate and sensing the intensity of the laser light reflected by the diffuse reflection unit.

The calibration unit compares the intensity of the laser light measured by the optical sensor unit with a reference value, and determines that the laser light is incident on an arbitrary diffuse reflection point when the intensity of the measured laser light exceeds the reference value. And a comparing unit for transmitting the pattern information unit to the pattern information unit, wherein the pattern information unit determines and stores the data value of the pattern information when the laser light is incident on the diffuse reflection unit as pattern correction data.

The pattern information unit may include a pattern row data storage unit which stores data representing coordinate values corresponding to pattern information to be formed on the substrate; And a pattern correction data storage unit for storing pattern correction data obtained by correcting a coordinate value of the pattern information using the pattern correction information extracted by the calibration unit.

The calibration plate includes a light transmissive substrate and diffuse reflection grooves formed on the light transmissive substrate, the diffuse reflection grooves are formed on the light transmissive substrate at a predetermined depth, and irregularities are formed on an inner surface of the diffuse reflection groove.

The calibration plate is composed of a light-transmissive substrate and a diffuse reflection protrusion formed on the light-transmissive substrate, wherein the diffuse reflection protrusion is formed to protrude to a predetermined height, and irregularities are formed on a surface of the diffuse reflection protrusion.

The calibration plate may include a light transmissive substrate and a first diffuse reflection groove formed on one surface of the light transmissive substrate; And a second diffuse reflection groove formed on the other surface of the light transmissive substrate at a position corresponding to the first diffuse reflection groove.

The calibration unit further includes a mirror unit disposed opposite the optical sensor unit to reflect the laser light reflected by the diffuse reflection unit of the calibration plate toward the optical sensor unit.

As in the present invention, after arranging a calibration plate on which a diffuse reflection is formed on the transparent substrate, pattern correction data is extracted by detecting the intensity of the diffusely reflected light of the laser beam scanned by the calibration plate, and using the extracted pattern correction data. By calibrating the distortion value of the laser beam, it is possible to provide a calibration system of the laser beam scanning apparatus that can correct the pattern distortion at a simple and low cost.

It is possible to provide a calibration system of a laser beam scanning device that improves precision and facilitates equipment design and maintenance.

1 is a schematic configuration diagram of a general laser beam scanning apparatus.
2 is a diagram illustrating a distortion phenomenon of a laser beam due to an operation of a scan unit of a laser beam scanning apparatus.
3A is a view showing a distorted shape of the laser beam due to the scanning portion of the laser beam scanning apparatus, FIG. 3B is a view showing a distorted shape of the laser beam due to the optical portion of the laser beam scanning apparatus, and FIG. 3C is a pattern to be formed. The distorted shape of the laser beam finally appearing on the substrate.
FIG. 4A is a pattern shape to be formed on a substrate, FIG. 4B is a diagram showing a distorted shape of a laser beam formed on a substrate when operating the laser beam scanning apparatus using pattern information before correction, and FIG. 4C is a calibration A diagram showing pattern correction data that has been processed.
5 is a schematic configuration diagram of a calibration system of a laser beam scanning apparatus according to an embodiment of the present invention.
FIG. 6 is a functional block diagram of a calibration system of the laser beam scanning apparatus shown in FIG. 5.
FIG. 7 is a schematic configuration diagram of the calibration unit shown in FIG. 6.
FIG. 8 is a schematic configuration diagram of the pattern information unit shown in FIG. 6.
9 and 10 are conceptual views illustrating the operating principle of the calibration unit.
FIG. 11 is a partially enlarged cross-sectional view of a calibration plate of a calibration unit, FIG. 12 is a partially enlarged cross-sectional view of another embodiment of a calibration plate, and FIG. 13 is a partially enlarged cross-sectional view of another embodiment of a calibration plate.
14 is a schematic configuration diagram of a calibration system of a laser beam scanning apparatus according to another embodiment of the present invention.
FIG. 15 is a schematic configuration diagram of the calibration unit shown in FIG. 14.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 4A is a pattern shape to be formed on a substrate, FIG. 4B is a diagram showing a distorted shape of a laser beam formed on a substrate when operating the laser beam scanning apparatus using pattern information before correction, and FIG. 4C is a calibration A diagram showing pattern correction data that has been processed.

4A is a diagram illustrating data representing coordinate values corresponding to pattern information to be formed on a substrate, that is, pattern raw data. In the case of this embodiment, a square pattern was set as pattern row data on the substrate.

FIG. 4B is a pattern form in which the scanner part is distorted into a pillow-shape and the optical part is distorted into a barrel-shape. 4C is a diagram illustrating pattern correction data generated by correcting pattern row data by reflecting a distortion value.

When the laser beam scanning apparatus is operated using the pattern correction data shown in FIG. 4C, a pattern to be formed on the substrate shown in FIG. 4A may be obtained. The calibration system extracts the pattern correction data by reflecting the distortion value so that the laser beam can be scanned as the pattern row data on the substrate, and checks whether the extracted pattern correction data matches the pattern to be formed on the substrate. do.

5 is a schematic configuration diagram of a calibration system of a laser beam scanning apparatus according to an embodiment of the present invention, and FIG. 6 is a functional block diagram of the calibration system of the laser beam scanning apparatus illustrated in FIG. 5.

5 and 6, a calibration system of a laser beam scanning apparatus according to an embodiment of the present invention may include a laser light source unit 100, a scanner unit 200, an optical unit 300, and a pattern information unit 400. And a calibration unit 500, a control unit 600, and a stage 900.

The laser light source unit 100 generates and outputs laser light. In the present embodiment, only the laser light source is disclosed as a component, but is not limited thereto, and may further include a reflection mirror for changing the direction of the laser light or an optical attenuator for adjusting and outputting the power of the laser light.

The scanner unit 200 is installed at the rear end of the laser light source unit 100 and adjusts the vertical and horizontal displacements of the laser light incident from the laser light source unit 100 to reflect the laser light onto the substrate in a desired pattern form. Do this.

The scanner unit 200 is composed of a combination of the first galvano scanner 210 and the second galvano scanner 220, the first galvano scanner 210 is a first axis direction of the laser light incident from the laser light source. The displacement is adjusted, and the second galvano scanner 220 performs the function of adjusting the displacement in the second axis direction perpendicular to the first axis direction.

The first galvano scanner 210 includes a first galvano mirror 211 and a first galvano mirror driver 212, and the second galvano scanner 220 includes a second galvano mirror 221 and a second galvano mirror 221. 2 galvano mirror driver 222.

The first galvano mirror 211 is rotatably installed to reflect the laser light, and the first galvano mirror driver 212 is installed at the end of the first galvano mirror 211, thereby providing a first galvano mirror ( While supporting 211, the first galvano mirror 211 is rotated. The second galvano mirror 221 is rotatably installed to reflect the laser light, and the second galvano mirror driver 222 is installed at an end of the second galvano mirror 221, thereby providing a second galvano mirror. While supporting the mirror 221, the second galvano mirror 221 is rotated.

The laser light reflected by the first galvano mirror 211 is incident on the second galvano mirror 221, and the laser light incident on the second galvano mirror 221 is reflected in the direction of the substrate.

The optical unit 300 is installed between the scanner unit 200 and the substrate 800, and the optical unit 300 adjusts the laser light incident from the scanner unit 200 to be focused on the substrate 800. Perform the function.

The pattern information unit 400 stores information on a pattern to be formed on the substrate 800, stores pattern correction data extracted through the calibration unit 500, and sends the pattern correction data to the control unit 600. Perform the function of sending.

The calibration unit 500 uses a calibration plate and an optical sensor unit in which a diffuse reflection unit is formed at a plurality of points including a point corresponding to a pattern shape to be formed on an actual substrate, and the laser light incident and reflected by the diffuse reflection unit of the calibration plate. It detects the intensity, compares the detection result to extract and determine the pattern correction data value of the laser light, and transmits the determined pattern correction data to the pattern information unit 400.

The stage 900 supports the substrate 800 and may be driven to move the substrate 800 in a predetermined direction.

The control unit 600 performs a function of controlling the operations of the laser light source unit 100, the scanner unit 200, the optical unit 300, the pattern information unit 400, and the calibration unit 500.

FIG. 7 is a schematic configuration diagram of the calibration unit illustrated in FIG. 6, FIG. 8 is a schematic configuration diagram of the pattern information unit illustrated in FIG. 6, and FIGS. 9 and 10 are conceptual views illustrating an operation principle of the calibration unit. .

7, 9, and 10, the calibration unit 500 includes a calibration plate 510, an optical sensor unit 530, and a comparator 550.

The calibration plate 510 includes a light transmissive substrate 511 and a diffuse reflection portion 515. The calibration plate 510 diffuses the laser light incident on the diffuse reflection unit 515 and reflects the reflected light to the optical sensor unit 530.

The light transmissive substrate 511 uses a substrate made of a light transmissive material through which laser light can be transmitted. The diffuse reflection portion 515 is formed on the light transmissive substrate 511 and is formed in the form of a groove or a protrusion, and forms a rough surface in comparison with the surface of another region.

A plurality of diffuse reflection portions 515 are formed on the light transmissive substrate 511. The diffuse reflection portions 515 are formed at a plurality of points to include a point corresponding to a pattern shape to be formed on the actual substrate. For example, when the pattern to be formed on the substrate is a square having a predetermined size, the diffuse reflection part 515 is formed to include a plurality of points corresponding to the trajectory of the square. In the present embodiment, the pattern shape to be formed on the substrate is square, and a plurality of diffuse reflection portions in the form of lattice are formed on the light transmissive substrate. A part of the plurality of diffuse reflection portions is formed on a point disposed on the trace of the pattern shape to be formed on the substrate.

The optical sensor unit 530 is installed in the peripheral area of the calibration plate 510. In the present embodiment, the optical sensor unit 530 is installed adjacent to the four sides of the calibration plate 510, but the number or installation positions of the optical sensor unit 530 is not limited thereto. The optical sensor unit 530 detects the intensity of the laser light reflected by the diffuse reflection unit 515 of the calibration plate 510.

As shown in FIG. 9, when the laser light passing through the scanner unit and the optical unit is incident on the diffuse reflection part 515 of the calibration plate 510, the laser light is reflected by the diffuse reflection part 515 of the calibration plate 510. It will reflect laterally. The laser light reflected in the side direction is incident to the optical sensor unit 530, and the optical sensor unit 530 measures the intensity of the laser light.

On the other hand, as shown in Figure 10, when the laser light passing through the scanner unit and the optical unit is incident to the area where the diffuse reflection portion of the calibration plate 510 is not formed, the laser light passes through the light-transmissive substrate 511, The laser light reflected by the optical sensor unit 530 is absent or almost insignificant.

The comparison unit 550 of the calibration unit 500 compares the intensity of the laser light measured by the optical sensor unit 530 with a reference value, and when the intensity of the laser light measured exceeds the reference value, the random light reflection unit It is determined that it has entered the point 515, and the result is transmitted to the pattern information unit 400. At this time, the random diffuse reflection portion 515 is formed on any of the points of the pattern to be formed on the actual substrate. On the other hand, if there is a deviation between the pattern row data and the pattern correction data, when the laser light is scanned using the pattern row data, the laser light is not incident on the diffuse reflection part but is incident on the light-transmitting area, whereas the laser is generated using the pattern correction data. When the light is scanned, the laser light is incident on the diffuse reflection part.

Therefore, when the laser light is incident on the diffuse reflection part during the process of irradiating the laser while changing the data value for the pattern information, the optical sensor unit 530 measures the intensity of the incident laser light, and the comparison unit 550 measures The intensity of the laser light is compared with the reference value to determine whether the laser light is incident, and the determination result is transmitted to the pattern information unit 400.

The pattern information unit 400 determines the data value for the pattern information when the laser light is incident on the diffuse reflection part as pattern correction data and stores it.

Referring to FIG. 8, the pattern information unit 400 includes a pattern row data storage unit 410, a pattern correction data storage unit 420, and a data format conversion unit 430.

The pattern row data storage unit 410 stores data representing coordinate values corresponding to pattern information to be formed on the substrate, that is, data before correction.

The pattern correction data storage unit 420 stores a pattern correction data obtained by correcting a coordinate value of the pattern information using the pattern correction information extracted by the calibration unit.

The data format converter 430 converts the format of the data stored in the pattern row data storage 410 and the pattern correction data storage 420 and transmits the format to the control unit 600.

FIG. 11 is a partially enlarged cross-sectional view of a calibration plate of a calibration unit, FIG. 12 is a partially enlarged cross-sectional view of another embodiment of a calibration plate, and FIG. 13 is a partially enlarged cross-sectional view of another embodiment of a calibration plate.

Referring to FIG. 11, the calibration plate includes a light transmissive substrate 511 and a diffuse reflection groove 516. The diffuse reflection groove 516 has a groove formed on the light transmissive substrate 511 to a predetermined depth, and an uneven surface is formed on the inner surface of the groove to increase the roughness.

Referring to FIG. 12, the calibration plate includes a light transmissive substrate 511 and a diffuse reflection protrusion 517. The diffuse reflection protrusion 517 is formed to protrude on the light transmissive substrate 511 at a predetermined height, and irregularities are formed on the protrusion surface to increase the roughness.

Referring to FIG. 13, the calibration plate includes a light transmissive substrate 511, a first diffuse reflection groove 518, and a second diffuse reflection groove 519. The first diffuse reflection groove 518 has a groove formed on one surface of the light transmissive substrate 511 at a predetermined depth, and irregularities are formed on an inner surface of the groove to increase roughness. The second diffuse reflection groove 519 is formed on the other surface of the transparent substrate 511 at a position corresponding to the first diffuse reflection groove 518. Unevenness is formed in the inner groove of the second diffuse reflection groove 519. The second diffuse reflection groove 519 performs a function of diffusely reflecting light transmitted through the first diffuse reflection groove 518 and beneath the light transmissive substrate 511.

14 is a schematic configuration diagram of a calibration system of a laser beam scanning apparatus according to another embodiment of the present invention, and FIG. 15 is a schematic configuration diagram of a calibration unit shown in FIG. 14.

14 and 15, the calibration system of the laser beam scanning apparatus according to another embodiment of the present invention includes a laser light source unit 100, a scanner unit 200, an optical unit 300, a pattern information unit 400, And a calibration unit 500, a control unit 600, and a stage 900.

The calibration unit 500 includes a calibration plate 510, an optical sensor unit 530, a mirror unit 540, and a comparison unit 550. The calibration plate 510 includes a light transmissive substrate and a diffuse reflection part, and the calibration plate 510 performs a function of diffusely reflecting the laser light incident to the diffuse reflection part to reflect the light sensor part 530.

The optical sensor unit 530 is installed at one side of the calibration plate 510, and the mirror unit 540 is installed at the other side of the calibration plate 510, that is, the opposite side of the optical sensor unit 530. The laser light reflected by the diffuse reflection part of 510 is reflected toward the optical sensor part 530.

The comparator 550 compares the intensity of the laser light measured by the optical sensor unit 530 with the reference value, and determines that the laser light is incident to an arbitrary diffuse reflection point when the measured intensity of the laser light exceeds the reference value. The result is transmitted to the pattern information unit 400.

When the mirror unit 540 is disposed on the side of the calibration plate 510 as described above, the number of the optical sensor units 530 may be reduced while increasing the light sensitivity of the optical sensor unit.

What has been described above is only an exemplary embodiment of a calibration system of a laser beam scanning apparatus according to the present invention, and the present invention is not limited to the above-described embodiment, and as claimed in the following claims, the present invention Without departing from the gist of the present invention, one of ordinary skill in the art will have the technical spirit of the present invention to the extent that various modifications can be made.

100: laser light source unit
200: scanner unit
300: optical unit
400: pattern information unit
500: calibration unit
600: control unit

Claims (9)

In the calibration system of a laser beam scanning device,
A laser light source unit for generating and outputting laser light;
A scanner unit installed at a rear end of the laser light source unit and configured to adjust vertical and horizontal displacements of the laser light incident from the laser light source unit;
An optical unit installed between the scanner unit and the substrate, the optical unit adjusting the laser light incident from the scanner unit to focus on the substrate;
A calibration unit for extracting pattern correction data and correcting distortion values of the laser beam using the extracted pattern correction data; And
A pattern information unit storing information on a pattern to be formed on the substrate, and storing pattern correction data extracted through the calibration unit,
The calibration unit,
A calibration plate including a light-transmissive substrate and a plurality of diffuse reflection parts formed on the light-transmissive substrate, wherein the plurality of diffuse reflection parts include a point corresponding to a pattern shape to be formed on an actual substrate;
An optical sensor unit installed at a side of the calibration plate and sensing an intensity of laser light reflected by the diffuse reflection unit; And
When the intensity of the laser light measured by the optical sensor unit is compared with the reference value and the measured laser light intensity exceeds the reference value, it is determined that the laser light is incident on an arbitrary diffuse reflection point, and the result is a pattern information unit. Comparing unit for transmitting to; including;
The diffuse reflection portion of the calibration plate is formed of diffuse reflection grooves or diffuse reflection projections formed on the light transmissive substrate, irregularities are formed on the surface of the diffuse reflection grooves or the diffuse reflection projections,
And the pattern information unit determines and stores, as pattern correction data, data values for pattern information when the laser light is incident on the diffuse reflection part.
The method of claim 1,
The scanner unit,
A first galvano scanner for adjusting displacement in a first axial direction of the laser light incident from the laser light source unit;
A second galvano scanner installed at a rear end of the first galvano scanner, the second galvano scanner adjusting a displacement in a second axial direction of the laser light incident from the first galvano scanner; system.
delete delete The method of claim 1,
The pattern information unit,
A pattern row data storage unit for storing data representing coordinate values corresponding to pattern information to be formed on the substrate; And
And a pattern correction data storage unit for storing pattern correction data obtained by correcting coordinate values of the pattern information using the pattern correction information extracted by the calibration unit.
delete delete The method of claim 1,
The diffuse reflection groove,
A first diffuse reflection groove formed on one surface of the light transmissive substrate; And
And a second diffuse reflection groove formed on the other surface of the light transmissive substrate at a position corresponding to the first diffuse reflection groove.
The method of claim 1,
The calibration unit,
And a mirror unit provided on the opposite side of the optical sensor unit to reflect the laser light reflected by the diffuse reflection unit of the calibration plate to the optical sensor unit side.

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