KR20180069497A - Optical measuring unit, and mask inspection apparatus having the same - Google Patents

Abstract

Provided are a light measuring unit, and a mask inspecting apparatus having the same, wherein the light measuring unit comprises: a light irradiation unit disposed on one side of a holder for disposing a mask and configured to emit light from at least one line; and a light sensing unit disposed in close contact with the light irradiation unit and configured to detect light emitted from the light irradiation unit and reflected to the mask. Moreover, the light irradiation unit is formed to enable lights emitted from an individual point of at least one line to be emitted in the same direction toward the mask.

Description

TECHNICAL FIELD [0001] The present invention relates to an optical measuring unit and a mask inspection apparatus including the optical measuring unit.

And more particularly, to a light measurement unit in which light is emitted in a direction perpendicular to a mask and a mask inspection apparatus including the same.

Flat panel display devices such as Liquid Crystal Display Device, Plasma Display Panel Device and Organic Light Emitting Diode Display Device have a thin thickness and low consumption And is receiving the spotlight as a next-generation display device due to electric power.

In particular, the organic light emitting display device is a self light emitting display device, and unlike a liquid crystal display device, a separate light source is not required, and thus it can be manufactured in a light and thin shape. Further, the organic light emitting display device is advantageous not only in terms of power consumption in accordance with low voltage driving but also in response speed, viewing angle, and contrast ratio, and is being studied as a next generation display.

The organic light emitting diode display includes a thin film transistor connected to an organic light emitting diode (OLED) and an organic light emitting diode. The organic light emitting diode emits light of a specific wavelength based on a driving current transmitted through the thin film transistor.

The detailed structure of the organic light emitting diode includes an anode, a hole injection layer, a hole transfer layer, an emitting layer, an electron transfer layer, An electron injection layer, and a cathode are stacked in this order. As the anode, ITO (Indium Tin Oxide), which has small sheet resistance and good transparency, is mainly used. The organic thin film is composed of a multilayer of a hole injecting layer, a hole transporting layer, a light emitting layer, an electron transporting layer, and an electron injecting layer in order to increase the luminous efficiency. And since the organic thin film is very weak to moisture and oxygen in the air, a thin film is formed at the top to seal to increase the lifetime of the device.

At this time, an organic light emitting layer should be deposited on a glass substrate in a predetermined pattern, and a mask is required in various deposition processes. For example, a desired pattern-shaped light-emitting layer can be formed by depositing a desired pattern-shaped mask on a substrate and performing vapor deposition.

The mask used in such a deposition process may be made of a metal material, and as the large panel extends, the size of the mask also becomes large, which may cause the mask to sag.

However, the pattern formed on the mask is very fine, and if the mask is deflected by its own weight, an organic light emitting layer is not formed on the substrate in a desired pattern, resulting in defects.

Further, the mask may not be in contact with the substrate if the thickness of the mask is not uniform or the flatness of the mask itself is not ensured. In this case, organic matter may not be deposited at a desired position of the substrate, resulting in defects or deterioration of the quality of the manufactured organic light emitting display device.

[Related Technical Literature]

1. Non-uniformity inspection apparatus and nonuniform inspection method (Korean Patent Application No. 10-2006-0029878)

The inventors of the present invention have found that the organic material deposited on the substrate is not deposited at the desired position due to the fact that the flatness of the mask is not maintained in the process of depositing the organic material on the substrate using the produced mask, Degradation, or failure. Accordingly, the inventors of the present invention invented a light measuring unit and a mask inspection apparatus including the light measuring unit, which can determine the flatness of the mask by measuring the flatness of the mask before depositing the organic material on the substrate using the mask.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a light measurement unit capable of grasping the flatness of a mask before depositing an organic material on a substrate using the mask, and a mask inspection apparatus including the same.

Another problem to be solved by the present invention is to provide a light measuring unit and a mask inspection apparatus including the same, which can ensure reliability because the deviation of the repeated measured values is not large when the flatness of the mask is repeatedly inspected.

The problems of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a light measuring unit comprising: a light irradiating unit disposed on one side of a holder configured to dispose a mask and configured to emit light in at least one line; And a light sensing unit arranged adjacent to the light irradiating unit and configured to detect light reflected on the mask, wherein the light irradiating unit irradiates light emitted from each point of the at least one line in the same direction toward the mask .

The light measuring unit according to the embodiment of the present invention is characterized in that light emitted at each point of the line of the light irradiating portion is diverted in the same direction toward the mask so that the light reflected by the mask is reflected by the incident angle and the reflection angle, It is possible to reduce the deviation from the outside.

According to an aspect of the present invention, there is provided a mask inspection apparatus comprising: a holder configured to dispose a mask; a holder disposed below the holder; And a moving unit for moving the light measuring unit at least in one axis, wherein the light measuring unit comprises: a light irradiating part arranged on one side of the holder and configured to emit light in at least one line; And an optical sensing portion arranged to detect light reflected from the mask and emitted from the light irradiation portion, wherein the light irradiation portion is made such that light emitted at each point of the at least one line is diverged in the same direction toward the mask.

The mask inspection apparatus according to an embodiment of the present invention irradiates the light emitted from the light irradiating unit toward the mask in a direction perpendicular to the plane formed by the mask so as to reduce light deviated to the outside of the optical sensor by diffuse reflection.

The details of other embodiments are included in the detailed description and drawings.

The present invention is characterized in that light emitted from each point of the line of the light irradiating unit is diverged in a certain direction toward the mask so that light reflected on the mask is diverted to the outside of the optical sensor by reflection by the incident angle and the reflection angle There is an effect that it can be reduced.

The present invention also provides a mask inspecting apparatus that irradiates light emitted from a light irradiating unit toward a mask in a direction perpendicular to a plane formed by a mask and adjusts an amount of light incident on the light sensor by irregular reflection, Measurement accuracy can be improved.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the specification.

1 is a schematic perspective view of a mask inspection apparatus according to an embodiment of the present invention.
2A and 2B are partially enlarged plan views of the region A shown in FIG. 1 in different directions.
Fig. 3 is a perspective view showing a light measurement unit to explain light emitted from the light measurement unit shown in Fig. 2A. Fig.
FIGS. 4A and 4B are cross-sectional views for explaining that light emitted from a light measuring unit according to an embodiment of the present invention is reflected on a mask.
FIG. 5 is a graph comparing deviations of measured values of flatness of a mask repeatedly using a mask inspection apparatus according to an embodiment of the present invention and a mask inspection apparatus according to a comparative example.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, and the like disclosed in the drawings for describing the embodiments of the present invention are illustrative, and thus the present invention is not limited thereto. Like reference numerals refer to like elements throughout the specification. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Where the terms "comprises", "having", "done", and the like are used in this specification, other portions may be added unless "only" is used. Unless the context clearly dictates otherwise, including the plural unless the context clearly dictates otherwise.

In interpreting the constituent elements, it is construed to include the error range even if there is no separate description.

In the case of a description of the positional relationship, for example, if the positional relationship between two parts is described as 'on', 'on top', 'under', and 'next to' Or " direct " is not used, one or more other portions may be located between the two portions.

It is to be understood that an element or layer is referred to as being another element or layer " on ", including both intervening layers or other elements directly on or in between.

Although the first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are used only to distinguish one component from another. Therefore, the first component mentioned below may be the second component within the technical spirit of the present invention.

Like reference numerals refer to like elements throughout the specification.

The sizes and thicknesses of the individual components shown in the figures are shown for convenience of explanation and the present invention is not necessarily limited to the size and thickness of the components shown.

It is to be understood that each of the features of the various embodiments of the present invention may be combined or combined with each other, partially or wholly, technically various interlocking and driving, and that the embodiments may be practiced independently of each other, It is possible.

Various embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

1 is a schematic perspective view of a mask inspection apparatus according to an embodiment of the present invention. 2A and 2B are partially enlarged plan views of the region A shown in FIG. 1 in different directions.

Referring to FIG. 1, a mask inspection apparatus 100 includes a holder 110, a light measurement unit 200, and a mobile unit 120.

Referring to FIG. 2A, a holder 110 supports a sequentially stacked mask 310, a glass 320, and a magnet 330. FIG. The holder 110 is moved up and down by the holder moving part 105 disposed on the upper plate 103 of the mask inspection apparatus 100. [ The holder 110 is provided with a mask 310 and a glass 310 so that the light measuring unit 200 disposed below can easily irradiate the mask 310 with light and easily detect the light reflected by the mask 310. [ 320 and the magnet 330 are supported.

Referring again to Figure 1, the mobile unit 120 moves the light measuring unit 200 at least in one axis. The mobile unit 120 is connected to the light measuring unit 200 so that the light measuring unit 200 moves under the mask and moves the flatness degree of the mask to scan.

The mobile unit 120 includes a first axis moving rail 122, a second axis moving rail 124, and a vertical moving rail. The first axis moving rail 122, the second axis moving rail 124 and the up and down moving rails are orthogonal to each other so that the moving unit 120 can be made to move the optical measuring unit 200 in three mutually orthogonal axes have.

At this time, since the area in which the optical measuring unit 200 can scan at one time is narrower than the entire area of the mask 310, the moving unit 120 moves the optical measuring unit 200 in a scanning direction The optical measuring unit 200 is moved in a direction perpendicular to the scanning direction so that the unscanned area of the mask 310 can be scanned.

2A and 2B, FIG. 2A is a plan view of the X-axis and Z-axis planes shown in the drawing, and FIG. 2B is a plan view of the Y-axis and Z-axis planes of FIG.

The light measuring unit 200 is disposed below the holder 110. The light measuring unit 200 irradiates the lower surface of the mask 310 under the holder 110 with light. Then, the light measurement unit 200 is configured to detect the light reflected from the lower surface of the mask 310. Specifically, the light measuring unit 200 includes a light irradiating unit 210 configured to emit light, and a light sensing unit 230 configured to detect light reflected on the mask 310. [ On the other hand, the light irradiating unit 210 and the light sensing unit 230 are disposed on the plate 205 and are integrally moved.

The light irradiating unit 210 is disposed under the holder 110 and is configured to emit light in at least one line. Specifically, in FIG. 2A, the thickness direction of the light emitted from the light irradiation unit 210 is shown, and in FIG. 2B, the length direction of the light emitted from the light irradiation unit 210 is displayed. That is, the light emitted from the light irradiation unit 210 is diverged while forming a line in the longitudinal direction shown in FIG. 2B.

The light irradiation unit 210 irradiates light toward the lower surface of the mask 310 supported by the holder 110. At this time, the irradiated light is irradiated perpendicularly to the lower surface of the mask 310. The irradiated light is diffused to the mask 310. Some of the reflected light is incident on the optical sensing unit 230, and the optical sensing unit 230 detects the incident light.

The light irradiating unit 210 includes a light source 212 and a light transducer 214 which are disposed in the light traveling direction. At this time, the light source 212 may be a light emitting diode. And the light source 212 emits light toward the optical transducer 214.

The optical transducer 214 is configured to pass through the light from the light source 212 and to emit a line. Specifically, referring to FIGS. 2A and 2B, light passing through the optical converter 214 is diverted toward the mask 310 in a line extending in the Y-axis direction based on the coordinates shown in the drawing. That is, the light emitted from the optical converter 214 is formed to be long in the Y-axis direction.

The light sensing portion 230 is disposed adjacent to the light irradiation portion 210 and is configured to detect the light emitted from the light irradiation portion 210 and reflected on the mask 310. [ Specifically, the light emitted from the light irradiating unit 210 is reflected by the protrusion 311 formed on the lower surface of the mask 310 or the lower surface of the mask 310 and is directed toward the light sensing unit 230, 230 can detect the degree of flatness of the mask 310. The light sensing unit 230 is disposed to be spaced apart from the light irradiation unit 210 and the light measurement unit 200 in the scanning direction.

The optical sensing unit 230 includes a mirror 232, a condenser lens 234, and an optical sensor 236.

The mirror 232 reflects the light reflected back from the surface of the mask 310 and reflects the light so that the path changes toward the optical sensor 236. [ The mirror 232 is disposed on the upper side of the lens 234. The mask 310 is disposed obliquely with respect to the lens 234 so that the light reflected by the mask 310 and incident thereon can enter the photosensor 236 through the lens 234.

The lens 234 is disposed between the mirror 232 and the optical sensor 236. The lens 234 collects the light reflected through the mirror 232 and emits the light to the optical sensor 236.

The light sensor 236 detects light passing through the lens 234. The optical sensor 236 is interlocked with a control unit (not shown), and information on the level of the flatness of the mask 310 is measured at the lower end of the mask 310 in consideration of the coordinate and the scanning direction of the optical measuring unit 200 Lt; / RTI >

The optical sensor 236 may be a charge-coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS), which detects incident light. The optical resolution of the optical sensor 236 is preferably 13 占 퐉 or less so that the error is less than 1 占 퐉 when the measurement is repeated with respect to the degree of flatness of the mask 310 measured by the optical sensor 236. [ That is, the size of one sensor of the device that is the optical sensor 236 may be 13 μm or less.

At this time, the mask 310 inspected by the mask inspection apparatus 100 of the present invention may be a fine metal mask (FMM) 310. A protrusion 311 is formed around the hole 312 through which the deposition material such as organic matter on the lower surface of the fine metal mask 310 passes. Therefore, the light emitted from the light irradiation unit 210 of the light measurement unit 200 can be irregularly reflected by this protrusion 311 (see Fig. 4A).

As described above, the direction in which the line of light emitted from the light converter 214 extends is a direction extending in the Y-axis direction in the drawings. The direction in which the light measuring unit 200 is moved to inspect the degree of flatness of the mask 310, that is, the scanning direction is the X-axis direction. Therefore, the extending direction of the line through which the light of the optical converter 214 is diverted can be perpendicular to the scanning direction of the light measuring unit 200. [

The extending direction of the line perpendicular to the scanning direction is irradiated from the light irradiating unit 210 so that the light reflected by the lower surface of the mask 310 can be easily irradiated to the light irradiating unit 210 and the light sensing unit 230 spaced in the scanning direction To enter the company.

For example, when the line that emits the light of the optical converter 214 coincides with the scan direction, the light emitted from the light irradiation unit 210 is irradiated simultaneously to the plurality of protrusions 311 formed on the lower surface of the mask 310 do. The light is diffusely reflected depending on the shape of the plurality of protrusions 311. Some of the diffracted lights are incident on the optical sensing unit 230, which is detected by the optical sensor 236.

The light emitted from the light irradiating unit 210 is simultaneously irradiated to a very large number of protrusions 311 formed on the lower surface of the mask 310 so that light detected by the light sensing unit 230 is reflected by the protrusion 311 It is difficult to know whether the mask 310 is reflected or not. Therefore, it is difficult to measure the degree of flatness of the mask 310 accurately. Therefore, it is preferable that the formation direction of the line that emits the light of the optical converter 214 is perpendicular to the scanning direction of the light irradiation unit 210.

Meanwhile, as described above, the holder 110 supports the mask 310, the glass 320, and the magnet 330. The above-described configuration can also be obtained in the case of depositing a deposition material such as an organic material by using a mask 310 on a raw substrate. That is, when measuring the degree of flatness or degree of distortion of the mask 310 using the light measuring unit 200, the measurement is not performed only on the mask 310, but the conditions for depositing the organic material on the substrate Lt; / RTI >

Accordingly, the mask inspection apparatus 100 of the present invention can more easily predict the degree of deformation of the mask 310, which may occur when depositing an organic material on a substrate using the mask 310.

The mask inspection apparatus 100 includes a PPA (Pixel Position Accuracy) measurement device for checking whether the glass 320 and the hole 312 of the mask 310 are disposed at an accurate position, And a Gauss Meter for measuring a magnetic force for measuring whether a force is applied to the mask 310 by a uniform magnetic force from the entire surface of the mask 310. At this time, the PPA measuring device and the Gaussmeter may be disposed adjacent to the light measuring unit 200.

Fig. 3 is a perspective view showing a light measurement unit to explain light emitted from the light measurement unit shown in Fig. 2A. Fig. For convenience of description, it should be noted that FIG. 3 shows only the optical measurement unit among the configurations shown in FIG. 2A.

Referring to FIG. 3, the light measuring unit 200 includes a light irradiating unit 210 and a light sensing unit 230. The light irradiating unit 210 includes a light source 212 and a light transducer 214 and the light sensing unit 230 includes a mirror 232, a lens 234, and a light sensor 236.

The light irradiation unit 210 has a slit 223 having a rectangular shape at the top. The light emitted from the light source 212 is incident on the lower portion of the optical transducer 214 and is diverted toward the mask 310 disposed at the upper portion through the slit 223.

The slits 223 are formed in a rectangular shape and are formed to have a width direction of a short length and a longitudinal direction of a long length. The light emitted from the slit 223 is diverged in the longitudinal direction of the slit 223. At this time, light emitted from the slit 223 is referred to as a beam 225.

On the other hand, as described above, the beam 225 emerging from the slit 223 is diverged in a direction perpendicular to the plane formed by the upper surface of the mask 310. And, unlike that shown in FIG. 3, the optical converter 214 may have two or more slits so that light is emitted from two or more lines.

The beam 225 has a thickness in a direction corresponding to the width 223a of the slit and a length in a direction corresponding to the length 223b of the slit. The thickness of the beam 225t is approximately 100 占 퐉 to 1000 占 퐉, and the length of the beam 225l is approximately 10 mm. However, by modifying the shape of the slit 223, the thickness of the beam 225 and the length of the beam 225 can be varied.

On the other hand, the light forming the beam 225 exiting the slit 223 is parallel to each other. Specifically, the first point P1, which is the different point of the slit 223, and the first light L1 and the second light L2, which exit the slit 223 at the second point P2 and form the beam 225, (L2) may be parallel to each other.

Since the light emitted from the slit 223 is parallel to each other, the light emitted from the slit 223 travels approximately the same distance toward the mask 310 and can reach the mask 310.

At this time, the light irradiated to the mask 310 is reflected so that the angle of incidence with the surface of the mask 310 is equal to the reflection angle. That is, when light is irradiated to the mask 310, the incident angle and the reflection angle form the same angle and are reflected from the surface of the mask 310. If light is emitted at this time, there is a lot of light that escapes to the outside, so the probability of occurrence of errors in repeated measurement increases.

Specifically, when the light emitted from the light source 212 forms a radiation pattern, the light is irradiated to the mask 310 at an angle other than 90 degrees, not perpendicular to the plane formed by the upper surface 310a of the mask. Therefore, the light reflected on the surface of the mask 310 is reflected in a direction away from the light source 212 or the optical sensor 236 because the incident angle and the reflection angle are the same.

In this case, when the same interval is repeatedly measured, the amount of light introduced into the optical sensor 236 varies, so that it is difficult to ensure the reliability thereof.

The light irradiating unit 210 according to an embodiment of the present invention irradiates light in a direction perpendicular to the plane formed by the mask 310 so that the light emitted from the light source 212 or the light sensor 236 Can be reduced. Therefore, more reliable results can be obtained even by repeated measurement.

On the other hand, the light irradiating unit 210 according to an embodiment of the present invention is irradiated perpendicularly to the plane formed by the mask 310, and the irradiated light rays are not irradiated and irradiated in parallel with each other. As a result, as the radiation is radiated to the outside, errors in repeated measurement are reduced. As a result, reliability is improved.

The longitudinal direction of the slit 223 is formed in a direction perpendicular to the direction in which the light irradiating unit 210 and the light sensing unit 230 are spaced apart. That is, the light irradiating unit 210 and the light sensing unit 230 are spaced apart from each other in the X-axis direction which is the scanning direction of the light measuring unit 200. The longitudinal direction of the slit 223 is formed in the Y-axis direction.

The longitudinal direction of the slit 223 is a direction in which the moving unit 120 moves the optical measuring unit 200 so that the light measuring unit 200 irradiates the light to the mask 310 and easily detects the reflected light. And perpendicular to each other. This will be described in detail later with reference to FIG. 4A.

FIGS. 4A and 4B are cross-sectional views for explaining that light emitted from a light measuring unit according to an embodiment of the present invention is reflected on a mask. 4A and 4B are views showing a state in which a beam is irradiated on a lower surface of a mask in a thickness direction.

The lower surface of the mask 310 to which the beam 225 is irradiated has a plurality of projections 311 and holes 312. Since the diameter of the hole 312 formed in the mask 310 is approximately 20 μm to 30 μm and the thickness of the beam 225 is approximately 100 μm to 1000 μm as described above, The beam 225 is irradiated to a region extending through the plurality of holes 312 and the protrusion 311.

Specifically, referring to FIG. 4A, there are three holes 312 located within the thickness of the light emitted from the light irradiation unit 210. Then, four protrusions 311 may be irradiated to the thickness region of the light of the line beam 225.

The light irradiated on the lower surface of the mask 310 is reflected by the first inclined surface 311a, the second inclined surface 311c and the end surface 311b of the protrusion 311 and is reflected in all directions. In particular, the first inclined plane 311a and the second inclined plane 311c are formed in a curved line, and the light incident on the first inclined plane 311a and the second inclined plane 311c is irregularly reflected.

At this time, since the optical sensor 236 is disposed in the opposite direction of the scanning direction, a part of the light reflected by the lower surface of the mask 310 in the A direction can be detected by the optical sensor 236. [ And the light reflected in a direction other than the A direction including the B direction is not detected by the optical sensor 236. [

That is, the lower surface of the mask 310 is irradiated with light so that the light irradiating unit 210 and the light sensing unit 230 are spaced apart from each other in the scanning direction and the thickness of the beam 225 is arranged in the direction perpendicular to the scanning direction, The optical sensing unit 230 can detect the flatness of the mask 310 in the thickness direction of the beam 225. [

Next, referring to FIG. 4B, when the light measuring unit 200 is moved in the scanning direction, the light emitted from the light irradiating unit 210 is irradiated to the mask 310. Three protrusions 311 are located in the thickness region of the light, and the light escapes through the four holes 312.

In this case, the lights projected on the three protrusions 311 are irregularly reflected by the first inclined plane 311a and the second inclined plane 311c as described above. Some of the diffracted lights are reflected toward the mirror.

The plurality of protrusions 311 and the plurality of holes 312 are included in the thickness region of the light emitted from the light irradiation unit 210 so that the light measurement unit 200 moves in the scanning direction, The amount of light reflected from the mask 310 and introduced into the photosensor 236 may be substantially constant.

Accordingly, it is possible to grasp that the mask 310 is not flat in a section where the amount of light introduced into the optical sensor 236 is suddenly changed, and a wave in which the distortion or the surface of the mask 310 is curved is generated .

Meanwhile, when the slit 223 of the optical transducer 214 is formed in the same direction as the scanning direction, the longitudinal direction of the beam 225 is formed in the same direction as the scanning direction. In this case, the optical sensor detects the diffuse reflection occurring in the region corresponding to the longitudinal direction of the beam 225. At this time, since the diffused light increases at the surface of the mask 310 flowing into the optical sensor, the accuracy of the flatness of the mask 310 that can be detected by the optical sensor is lowered.

Also, since the amount of light that is reflected by the lower surface of the mask 310 and enters the photosensor increases, there is a danger that the error of the repeated measurement of the flatness of the mask 310 becomes large.

FIG. 5 is a graph comparing deviations of measured values of flatness of a mask repeatedly using a mask inspection apparatus according to an embodiment of the present invention and a mask inspection apparatus according to a comparative example.

The graph of FIG. 5 is a graph showing an average of deviations of values detected by the optical sensor for 10 times when the same section of the mask is repeatedly measured 10 times using a mask inspection apparatus.

The X-axis of the graph represents each point of the mask measured using a mask inspection apparatus, and the Y-axis represents an average of repeatedly measured detection value deviations at each point of the mask.

The comparative example is a graph showing an average of the deviation of the values detected by the optical sensor for 10 times when the mask is repeatedly measured by using a light source radiated from the mask inspection apparatus of the present invention. That is, the comparative example is a graph showing an average of the deviation of the values detected by the optical sensor by repeatedly measuring the mask using light spreading widely from the light source.

In the embodiment, when the mask is repeatedly measured using the light irradiation unit that does not spread the light around, that is, the light is not radiated, by using the mask inspection apparatus of the present invention, the deviation As shown in FIG.

In the graph, it can be seen that the difference in the repeated measured values of the comparative example using the emitted light source is 4 μm at the maximum. In the embodiment using the light irradiating unit in which light is not radiated and irradiated to each other in parallel, the difference between the repeated measured values is less than 1 탆.

Therefore, when the flatness of the mask is measured by using the mask inspection apparatus according to an embodiment of the present invention, the deviation of the mask from the flatness of the mask is 1/4 And the reliability can be secured.

The optical measurement unit according to the embodiments of the present invention can be described as follows.

A light measuring unit according to an embodiment of the present invention includes a light irradiating portion disposed on one side of a holder configured to dispose a mask and configured to emit light in at least one line, and a light irradiating portion disposed adjacent to the light irradiating portion, And a light sensing portion configured to detect light reflected on the mask, wherein the light irradiating portion is made such that light emitted at each point of the at least one line is diverged in the same direction toward the mask.

According to another aspect of the present invention, the light irradiation unit can be configured to emit light in such a manner that the traveling directions of light emitted from the respective points of the at least one line are parallel to each other.

According to another aspect of the present invention, the light irradiating unit may include a light source that emits light, and a light transducer that is configured so that light emitted from the light source passes through and that the diverged light forms at least one line.

According to another aspect of the present invention, the direction in which at least one line of the optical transducer extends may be a direction perpendicular to the direction in which the light irradiation portion and the light sensing portion are spaced apart.

According to another aspect of the present invention, the optical sensing portion may include a mirror that is diverged from the light irradiating portion, reflects the light reflected on the mask, and an optical sensor configured to detect the light reflected from the mirror.

According to another aspect of the present invention, the optical sensing unit may further include a lens disposed between the mirror and the optical sensor, for condensing the light reflected by the mirror.

The mask inspection apparatus according to embodiments of the present invention can be described as follows.

A holder configured to dispose a mask according to an embodiment of the present invention; a light measuring unit disposed below the holder and configured to irradiate light to the mask and detect reflected light; And a light measuring unit includes a light irradiating unit disposed on one side of the holder and configured to emit light in at least one line and a light irradiating unit disposed adjacent to the light irradiating unit and configured to emit light from the light irradiating unit, Wherein the light irradiating portion is configured such that light emitted at each point of the at least one line is diverged in the same direction toward the mask.

According to another aspect of the present invention, the light irradiating unit may include a light source that emits light, and a light transducer that is configured so that light emitted from the light source passes through and that the diverged light forms at least one line.

According to another aspect of the present invention, the direction in which at least one line of the optical transducer extends may be a direction perpendicular to the direction in which the light irradiation portion and the light sensing portion are spaced apart.

According to another aspect of the present invention, the direction in which at least one line of the photo-converter extends is determined by the direction in which the light measuring unit moves the light measuring unit in order to illuminate the mask and detect the reflected light As shown in FIG.

According to another aspect of the present invention, the movable unit may be configured to move the optical measurement unit in three axes orthogonal to each other.

Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, it is to be understood that the present invention is not limited to those embodiments and various changes and modifications may be made without departing from the scope of the present invention. . Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. Therefore, it should be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100: mask inspection device
103: Top plate
105: holder moving part
110: holder
120: mobile unit
122: first axis moving rail
124: second axis moving rail
200: optical measuring unit
205: plate
210:
212: Light source
214:
223: Slit
223a: width of slit
223b: Length of the slit
225: beam
225t: beam thickness
225l: length of beam
230: Optical sensing unit
232: mirror
234: lens
236: Light sensor
310: mask
310a: upper surface of the mask
310b: the lower surface of the mask
311:
312: hole
320: Glass
330: Magnet

Claims (11)

A light irradiating portion disposed at one side of a holder configured to dispose a mask, the light irradiating portion being configured to emit light in at least one line; And
And an optical sensing portion disposed adjacent to the light irradiating portion and configured to detect light reflected from the mask, emitted from the light irradiating portion,
The light-
Wherein light emitted at each point of the at least one line is made to diverge in the same direction toward the mask. The method according to claim 1,
The light-
And wherein the traveling direction of the light emitted at each point of the at least one line is configured to emit light in parallel with each other. The method according to claim 1,
The light-
A light source for emitting light; And
And a light transducer configured to allow light emitted from the light source to pass therethrough and to emit light to form the at least one line. The method of claim 3,
The direction in which at least one line of the photo-
Wherein the light irradiating portion and the light sensing portion are perpendicular to a direction in which the light irradiating portion and the light sensing portion are spaced apart. The method according to claim 1,
The optical sensing unit includes:
A mirror which is diverged from the light irradiating portion and reflects light reflected on the mask; And
And an optical sensor configured to detect light reflected from the mirror. 6. The method of claim 5,
The optical sensing unit includes:
Further comprising a lens disposed between the mirror and the photosensor, for condensing the light reflected by the mirror. A holder configured to position a mask;
An optical measuring unit disposed below the holder and configured to irradiate light onto the mask and detect reflected light; And
And a moving unit for moving the light measuring unit at least in one axis,
Wherein the light measuring unit comprises:
A light irradiation unit disposed on one side of the holder and configured to emit light in at least one line; And
And an optical sensing portion disposed adjacent to the light irradiating portion and configured to detect light reflected from the mask, emitted from the light irradiating portion,
Wherein the light irradiating portion is configured to emit light emitted from each point of the at least one line in the same direction toward the mask. 8. The method of claim 7,
The light-
A light source for emitting light; And
And a light transducer configured to allow light emitted from the light source to pass therethrough and to emit light to form the at least one line. 9. The method of claim 8,
The direction in which at least one line of the photo-
Wherein the light irradiation unit and the optical sensing unit are perpendicular to a direction in which the light irradiation unit and the light sensing unit are spaced apart. 9. The method of claim 8,
The direction in which at least one line of the photo-
Wherein said optical measuring unit is arranged to be perpendicular to a direction in which said moving unit moves said optical measuring unit so as to irradiate said mask with light and to detect reflected light. 8. The method of claim 7,
The mobile unit includes:
And the optical measuring unit is moved in three axes orthogonal to each other.

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