JP2000230910A - Inspection apparatus and removing apparatus for substrate-adhering foreign matter and method and removing adhered foreign matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect an adhered foreign matter by irradiating the entire surface of a substrate with parallel laser light and detecting a change in illuminance of a passing light with an illuminance meter. SOLUTION: A glass substrate 6 is fixed through suction by supporting pins 4. A laser beam 100 from which an extra light has been eliminated by a slit 3 passes a position separated such a slight distance that the beam nearly touches a lower face of the substrate 6. An illuminance meter 8 is set to the side opposite to a laser light-projecting part 1, and measures an intensity of the laser beam 100 every time the swept laser beam enters the meter. The illuminance meter 8 moves in a lateral direction by the rotation of a ball screw 9 and the therefore can obtain an illuminance signal to a move distance as a function. If a foreign matter 7 is present, the illuminance decreases because of the shadow. The foreign matter 7 can be discovered accordingly. Moreover, a position coordinate of the foreign matter 7 can be obtained from a coordinate of the ball bearing 9 at the time when the signal is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting the presence or absence of foreign matter adhering to a substrate when manufacturing various substrates for manufacturing, for example, glass substrates for liquid crystal display devices and semiconductors, and More specifically, the present invention relates to an attached foreign matter removing apparatus and an attached foreign matter removing method for removing foreign matter found by this inspection.

[0002]

2. Description of the Related Art For example, when manufacturing a glass substrate of a liquid crystal display device or various substrates for manufacturing semiconductors, foreign substances such as dust and fragments of the substrate (called glass cullet in the case of a glass substrate) adhere to the substrate. In such a case, the pattern to be baked becomes incomplete, and in the case of close contact baking, the photomask (master) is damaged, and the yield of the product is reduced. Therefore, conventionally, various methods have been proposed for inspecting the adhesion of foreign substances on these substrates, and for removing foreign substances found by this inspection.

FIGS. 10 to 13 show Japanese Patent Application Laid-Open No.
FIG. 10 shows an inspection / removal device similar to the inspection / removal device for performing the abnormality inspection and removal disclosed in Japanese Patent Publication No. 150827, and FIG.
FIG. 11 is an external view of the removing device, FIG.
FIG. 4 is an explanatory view of a foreign matter removing device.

In FIG. 1, reference numeral 51 denotes a control box provided with a power supply unit therein, 5 denotes a mask supporting stage which is installed on the control unit 51 and supports an inspection object (also referred to as a mask) 6, and 54 denotes a hood. 10 shows an open state. Reference numeral 55 denotes a lamp house, inside which a light projection unit 19 for inspecting a mask flaw for projecting light for inspecting the mask 6 and a foreign matter inspection for inspecting foreign matter such as dust on the surface of the mask 6. Light emitting unit 57 (foreign matter inspection unit)
Is provided.

Further, a blower nozzle (also referred to as an air gun) 10 for jetting N ₂ gas is provided in order to blow off and remove foreign matters adhering on the surface of the mask 6. Since the blower nozzle 10 is installed on the XY drive mechanism 12, it is movably supported over the entire substrate surface.

For inspection of foreign matter on the surface of the mask 6, as shown in FIG. 11, a lamp 20 is turned on to irradiate the substrate surface of the mask 6 obliquely from above. And if there is foreign matter 24,
The light appears to shine only at the foreign matter 24. The foreign matter 24 found in this way is removed by a foreign matter removing device described below.

FIG. 12 shows the detailed structure of the blower nozzle 10. 13 is a gas pipe for sending N2 gas, 14 is a suction pipe for sucking dust and the like, and 15 is an exhaust path forming part for surely sucking the dust and the like into the suction pipe 14 before scattering to the surroundings. When the presence of foreign matter is confirmed by the above-described surface foreign matter inspection, the blower nozzle 10 is moved to a predetermined position by the XY drive mechanism 12, and the foreign matter is removed by the ejection of the N 2 gas and the function of the suction pipe 14. After removal, an inspection is required again for confirmation. However, while the blower nozzle 10 is on the surface of the glass plate, the light beam is blocked, so that the inspection cannot be performed. Therefore, after the removing operation, the XY drive mechanism 12 is operated. After retreating, the removal of foreign matter is confirmed by irradiation of the lamp 20 again.

FIG. 13 is a process flowchart for explaining the glass substrate manufacturing process before and after the inspection of the glass substrate 6 for explaining the problem of the conventional inspection method. After a glass plate is manufactured by a pre-process not shown, a resist is applied in step S1. After that, in step S2, a vacuum stage (not shown, a glass plate fixing jig provided with an air vent hole for sucking the glass plate on a precision flat processing surface as appropriate, the surface of the sucked glass plate is strictly flat. And printing and exposure processing can be performed accurately.)
And is kept in a precise plane. Then, the exposure processing is performed in S3, and the inspection is performed by the inspection apparatus of FIG. 10 described above in S4.

In the above-described inspection of the surface of the mask 6, even if the foreign matter 24 exists, the foreign matter 24 is not always surely glowing. If the foreign matter 24 does not shine, the foreign matter 24
Can not be found and will be overlooked. In addition, chipping of glass, generation of scratches, and attachment of foreign matter often occur in the step of suction and fixation by a vacuum stage in step S2 to which physical force is applied. There is a problem in that a baking process is performed on a defective glass plate due to adhesion of foreign matter, resulting in an extremely large waste. Further, there is a problem that it takes time since the re-inspection cannot be performed unless the blower nozzle 10 is moved, such as the movement of the blower nozzle 10 after the foreign matter is found, and the movement of the blower nozzle 10 after the foreign matter is removed. Was.

[0010]

In the conventional method for inspecting the adhered foreign matter on a substrate, the inspection is performed after the exposure processing. Therefore, even if the foreign matter is adhered in the previous step, the exposure processing is executed, and the wasteful processing is performed. There was a problem that there were many. Further, since the conventional apparatus for inspecting the adhered foreign matter on a substrate captures the reflection of light due to the foreign matter, there is a problem that foreign matter that is hardly reflected cannot be found. In addition, the conventional attached foreign matter removing device has to move the removing device along the path of the light for the foreign matter inspection. There is a problem that it takes a long time to repeat the process.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and removes extraneous matter in a step before exposure processing, thereby preventing unnecessary exposure processing from being performed. It is intended to obtain a foreign matter removing method. It is another object of the present invention to provide an attached foreign matter inspection apparatus capable of easily detecting foreign matter that is hardly reflected. In addition, the apparatus has a configuration that does not hinder the light path of the inspection of the attached foreign matter, and does not have to retract the removing device after removing the foreign matter,
It is an object of the present invention to obtain an attached foreign matter removing device that can immediately execute a re-inspection.

[0012]

SUMMARY OF THE INVENTION According to the present invention, there is provided an apparatus for detecting foreign matter on a substrate, which detects the presence or absence of foreign matter on the surface of the substrate. A light source that irradiates along the surface, an illuminometer that receives light passing along the surface and measures the intensity thereof, and a moving unit that moves the illuminometer to face the periphery of the substrate. It is provided. Since the illuminometer detects that the illuminance of light is reduced by the shadow of the adhered foreign matter,
It acts so as to detect the attached foreign matter without being affected by the type or the reflectance of the attached foreign matter.

Further, the light irradiated to the outside along the surface of the substrate is a laser beam, and the center position of the laser beam is in a range of 0.05 to 0.5 mm from the surface. is there. The light illuminated along the surface acts to enable the detection of even very small foreign objects.

The substrate is a glass plate for printing a display pattern of a liquid crystal display device.

[0015] Further, there is provided a rotary table for rotating the glass plate around an axis orthogonal to the laser beam.

An apparatus for removing adhering foreign matter according to the present invention uses a laser beam irradiated from the surface of a substrate in a range of 0.05 to 0.5 mm. 1mm to 5mm from the surface
XY moving to an arbitrary position on the surface while holding apart
And a drive mechanism. Since the gap of 1 mm between the air gun and the substrate surface is large enough for the inspection light to pass through, the gap acts to stop the ejection of air and perform the inspection again without retreating the air gun.

Further, the method for inspecting the adhered foreign matter on the substrate according to the present invention includes a step of adsorbing and fixing the glass plate for exposure processing, a step of inspecting the adhered foreign matter using a laser beam, and an air gun of an adhered foreign matter removing device. Removing the adhering foreign matter, performing a re-inspection of the adhering foreign matter using the laser beam without retreating the air gun, and exposing the glass plate to light. The pre-exposure removal method prevents unnecessary exposure work by detecting foreign matter before exposure, and the re-inspection performed without retracting the air gun can be performed immediately after the removal work. .

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 shows an outline of a substrate foreign matter inspection apparatus according to the present invention. In the following drawings, the same reference numerals as those in the drawings of the related art indicate the same or corresponding parts, and thus detailed description thereof will be omitted.
FIG. 2 is a side view of FIG. 1, and the structure is simplified for convenience of explanation. In the figure, reference numeral 1 denotes a laser projecting unit for generating a laser beam 100, which is thin (for example, having a diameter of 0.
A laser beam is emitted. Reference numeral 2 denotes a scan lens, which is configured by a lens or a mirror that bends an incident laser beam, and oscillates in a predetermined angle range by a vibration drive mechanism (not shown).
As shown in the figure, the laser beam can be swept over a wide angle.

A scan lens 2 is provided between the scan lens 2 and a glass substrate 6 to be inspected (a glass substrate may be a ceramic plate, a silicon substrate, or the like, and may be simply referred to as a substrate). The slit is used to narrow (for example, to about 0.1 mm) the thickness of the laser beam (up and down in FIG. 1) incident from the laser beam. The vertical position of the laser projector 1, the scan lens 2, and the slit 3 can be adjusted, and the vertical height of the laser beam 100 is irradiated along the lower surface 62 of the substrate 6 as shown in FIG. Alternatively, it is possible to adjust whether to irradiate along the upper surface 61.

Reference numeral 4 denotes a support pin for holding the glass substrate 6,
Although four are shown in the figure, depending on the size of the substrate 6,
More or less. Reference numeral 5 denotes a stage holding the support pins 4. Reference numeral 7 denotes a foreign matter (glass cullet in the case of a piece of a glass substrate) attached to the back surface 62 of the glass substrate 6 for the sake of explanation.
A size of about 1 mm is common. 8 is an illuminometer and FIG.
The intensity of the laser beam 100 passing along the surface of the substrate 6 is measured as shown in FIG. Reference numeral 9 denotes a device for driving the illuminance meter 8 with a ball screw to move around the substrate 6.

Although FIG. 1 shows the same device from the laser projector 1 to the illuminometer 8 in two directions XY with respect to the substrate 6, only one set of operations is described in the description of the operation. explain.

Next, the operation will be described with reference to FIGS. 1 and 2 and FIG. 3 showing changes in the output of the illuminance meter 8. FIG. The glass substrate 6 is fixed by suction of the support pins 4 (air holes (not shown) pass through the support pins 4 and are sucked by a vacuum pump (not shown)). The laser beam 100 from which excess light has been removed by the slit 3 is applied to the lower surface 4 of the substrate 6.
It passes through a position 20 which is a small distance of about 20 and almost touches 2. The distance 20 is set to a small value, for example, about 0.05 mm to 0.5 mm.

An illuminometer 8 is located on the opposite side of the glass substrate 6 from the side where the laser projector 1 is installed, and its intensity is measured each time the swept laser beam 100 enters. Since the illuminometer 8 moves in the horizontal direction by the rotation of the ball screw 9, the illuminance signal for the moving distance X is shown in FIG.
Can be obtained as a function as shown in the graph. In FIG. 3, reference numeral 21 denotes a sweep end of the laser beam 100, reference numeral 22 denotes a decrease in illuminance due to the shadow of the foreign matter 7, and reference numeral 23 denotes a decrease in illuminance due to the shadow of the support pin 4. The position coordinate x of the foreign matter 7 is changed to the ball bearing 9 when the signal is obtained.
Can be obtained from the coordinates of

In the above description, one (for example, Y-direction) laser projecting unit 1 and the illuminometer 8 opposed thereto are described, but the same operation is installed orthogonally thereto. An accurate position of the foreign matter 7 can be known from the obtained position coordinates x and y by another apparatus.
Of course, the laser beam 100 is irradiated in a fan shape, and is not irradiated orthogonally to the X and Y directions.
It is not a simple calculation, but it is not difficult.

In the above description, the thickness of the laser beam 100 narrowed by the slit 3 has been described to be, for example, 0.05 mm. However, the thickness may be about the size of the target foreign matter 7 to be found in the inspection. If the beam thickness is larger than the target size, the drop in illuminance when it becomes a shadow will decrease and the operation will be unstable, and if it is smaller than the target size, the original illuminance level will decrease and the detection sensitivity will also decrease. descend. Further, the beam 100 to be incident must be parallel to the surface of the substrate 6, but the degree is such that even when the beam 100 reaches the end of the substrate (the rear end where the beam 100 has passed), the foreign matter May be enough to reliably enter the beam 100.

Embodiment 2 FIG. FIG. 4 shows an outline of the attached foreign matter detection device according to the second embodiment of the present invention. 2 in the figure
Reference numeral 5 denotes a turntable which rotates around an axis orthogonal to the laser beam 100. A stage 5 is mounted on the turntable. The light from the laser projector 1 is maintained while the laser beam 100 and the substrate 6 are kept parallel. Stage 5 for launch direction
Can be arbitrarily adjusted. In the apparatus shown in FIG. 4, only one set is provided for the portion from the laser projector 1 to the illuminometer 8. Then, measurement is first performed in the X direction to obtain position data x1 of the foreign matter 7, and then the turntable 25 is obtained.
Is rotated by, for example, 90 degrees, and the position data y1 is obtained by measuring the substrate 6 from the 90-degree direction (Y direction). Thereafter, processing is performed in the same manner as in the first embodiment, and the position of the foreign matter 7 can be determined. The device shown in FIG. 4 has the advantage that only one device from the light projecting unit to the illuminometer is required, and also has the following other advantages.

Embodiment 3 Before describing the outline of the foreign object detection device according to the third embodiment of the present invention, problems of the device according to the first embodiment will be described with reference to FIG. FIG. 5 is a plan view of a surface of the glass substrate 6 through which the laser beam passes.
Reference numeral 26 (shown by hatching) is a shadow of the support pin 4. When the illuminometer 8 is located in the shadow 26, the laser beam 100
Illuminance cannot be measured. That is, there is an area on the surface of the substrate 6 that cannot be detected even if the foreign matter 7 exists. This unmeasurable area is shown as 27 in the figure.
The support pin 4 that produces the shadow, not just in the shadow 26
The effect is not small because it also occurs in front of.

Therefore, when the turntable 25 of the apparatus shown in FIG. 4 of the second embodiment is rotated to rotate the glass substrate 6 by an angle α degrees as shown in FIG.
7 can be changed. Area 27 in FIG. 5,
Since the position of the area 27 in FIG. 6 on the substrate 6 is clearly different, if the angle α is appropriately changed and the measurement is performed a plurality of times (for example, the measurement is performed a plurality of times every 30 degrees), the area 27 is substantially changed. The position of the foreign matter 7 can be specified without being affected by the shadow 26 or the area 27 that cannot be measured. If there are two or more data at two or more different values of α, the exact position of the foreign matter 7 can be obtained by calculating from a combination thereof.

Embodiment 4 FIG. 7 is a schematic view of a foreign matter removing device according to the present invention, and FIG. 8 is a side view thereof.
In the figure, 10 is an air gun for blowing high-pressure dry air, 11 is an exhaust port (intake port) connected to a vacuum cleaner (not shown), 12 is an air gun 10 and an exhaust port 11 mounted on the stage 5 at an arbitrary position on the stage 5. This is an XY drive mechanism that can be moved to the right. The XY drive mechanism 12 is driven by the ball screw 9. Air gun 10 and other equipment are all shown in FIG.
As shown in the figure, a predetermined distance 30 from the target surface 42 of the glass substrate 6 (for example, 1 mm to 5 m
m) It is installed so that it is separated. Of course this distance 3
0 is a distance where the high-pressure air ejected from the air gun 10 blows off the foreign matter 7 without any trouble, and is a gap where the laser beam 100 can pass without any trouble.

FIG. 9 is a flow chart for explaining the steps of removing foreign matter by the foreign matter removing apparatus shown in FIGS. Of the steps in each flow, the same steps as those described in FIG. 13 indicate the same steps.
Detailed description is omitted. In the fourth embodiment, after the step (S2) of suction-fixing to the vacuum stage, and
Before the printing exposure process (S3), the inspection of the attached foreign matter (S3)
Perform 4). Also, it is determined that there is a foreign substance on the surface (S5).
Then, the air gun 10 is moved (S6), and the high-pressure air is blown out to remove the foreign matter 7 (S7). Then, if the blowing of the high-pressure air is stopped, the re-inspection is immediately performed without retracting the air gun 10 (S4). Can be performed (the flow S8 in FIG. 13 is unnecessary).

[0031]

As described above, since the attached foreign matter inspection apparatus of the present invention catches the decrease in illuminance due to the shadow of the attached foreign matter, it can catch the foreign matter without being affected by the reflectance of the foreign matter. The effect that inspection errors hardly occur is obtained.

Further, since the thin laser beam is irradiated within a range of 0.05 to 0.5 mm from the surface of the inspection object, an effect that an extremely small foreign substance can be found can be obtained.

Further, since the present invention is applied to a glass substrate of a liquid crystal display device, it is possible to improve the production yield of the liquid crystal display device.

Further, since the rotary table is provided to rotate with the glass substrate placed thereon, the effect that only one set of the laser projector and one illuminometer is required is obtained.

Since the apparatus for removing foreign matter adhering to a substrate according to the present invention is provided with an air gun set at a distance of 1 mm to 5 mm from the surface to be removed as described above, even if the air gun is not retracted, the laser is The advantage is that foreign matter inspection can be performed through the beam.

According to the foreign matter removing method of the present invention, the foreign matter is removed before the exposure after the glass substrate is fixed by suction for the exposure processing, so that the waste of the exposure processing of the glass substrate can be eliminated. The effect is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an attached foreign matter inspection apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is an explanatory diagram of illuminance data of the apparatus of FIG. 1;

FIG. 4 is a configuration diagram of an attached foreign matter inspection apparatus according to a second embodiment.

FIG. 5 is an explanatory diagram of a shadow generated by a support pin.

FIG. 6 is an operation explanatory diagram of the attached foreign matter inspection device according to the third embodiment.

FIG. 7 is a configuration diagram of an attached foreign matter removing device according to a fourth embodiment.

FIG. 8 is a side view of FIG. 7;

FIG. 9 is a flowchart illustrating a method for removing an attached foreign matter using the attached foreign matter removing device of FIG. 7;

FIG. 10 is a configuration diagram of a conventional attached foreign matter inspection device.

11 is an explanatory diagram of the operation of the attached foreign matter inspection of FIG. 10;

12 is an explanatory diagram of the operation of removing the adhered foreign matter in FIG.

FIG. 13 is a flowchart illustrating a conventional attached foreign matter removing step.

[Explanation of symbols]

Reference Signs List 1 laser projection unit, 2 scan lens, 3 slit, 4 support pin, 5 stage, 6 glass substrate, 7 foreign matter, 8 illuminometer, 10 air gun, 1
1 exhaust port, 12 XY drive mechanism, 25 turntable, 26 shadow, 27 area that cannot be measured, 10
0 Laser beam

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G051 AA51 AA56 AA73 AB01 AC15 BA10 BB01 BB07 BC05 CA01 CA07 CB02 CD04 DA17 GC15 3B116 AA02 AB42 BB22 BB32 BB55 BB72 BB75 CC05 CD41 4M106 AA10 AA20 AB16 AB18 CA05 CA17 DB12 DH32 DJ02 DJ04 DJ06 DJ07 DJ14 DJ27 DJ31 DJ38 DJ40

Claims (6)

[Claims] 1. A foreign matter inspection device for inspecting the presence or absence of foreign matter on a surface of a substrate, comprising: a light source that irradiates light parallel to the surface of the substrate along the surface; An apparatus for inspecting adhering foreign matter on a substrate, comprising: an illuminometer for receiving the passed light and measuring the intensity thereof; and moving means for moving the illuminometer to face the periphery of the substrate. 2. A laser beam emitted along a surface of a substrate is a laser beam, and a center position of the laser beam is in a range of 0.05 to 0.5 mm from the surface. 2. The apparatus for inspecting foreign matter on a substrate according to claim 1. 3. The apparatus according to claim 2, wherein the substrate is a glass plate for printing a display pattern of the liquid crystal display device. 4. The apparatus according to claim 3, further comprising a rotary table for rotating the glass plate around an axis orthogonal to the laser beam. 5. An air gun provided in the attached foreign matter inspection device according to claim 2, which blows out high-pressure gas, and moves the air gun to an arbitrary position on the surface while holding the air gun at least 1 mm to 5 mm away from the surface. And an XY drive mechanism that performs the operation. 6. A process for adhering and fixing a glass plate for exposure treatment, a process for inspecting an attached foreign matter using the laser beam according to claim 2, and an attached foreign matter according to claim 5 based on the inspection result. A step of removing adhering foreign matter using an air gun of a removing device, a step of re-inspection of the attached foreign matter using the laser beam without retreating the air gun, and a step of exposing the glass plate to light. A method for removing adhering foreign matter from a substrate, comprising: