JP2005300395A - Foreign matter and flaw inspecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a foreign matter and flaw inspecting device, capable of efficiently detecting the foreign matter and flaws (pinholes) on a substrate, the height of the foreign matter and the depth of the flaws. <P>SOLUTION: The foreign matter and flaw inspecting device is equipped with a light source 101 for irradiating the substrate with an incident light 201, of which the optical axis is inclined at an angle θ and matching the focus of the incident light with the confocal surface 204, corresponding to the pinhole perpendicular to the optical axis of reflected light at a point (P) reflected by the surface of the substrate 105; an object lens 102 which condenses the reflected light and has the optical system of a confocal point arranged on the optical axis of the reflected light; the pinhole 103 at a position which is conjugate with the point (P) reflected by the surface of the substrate; an optical detection element 104 for detecting the reflacted light passed through the pinhole and a mechanism for scanning the substrate in an x-axis direction, inclined by the angle θ for optical axis. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a foreign matter and defect inspection apparatus, and more particularly, to an apparatus for inspecting foreign matters and defects (pinholes) on a color filter substrate used in a full-color organic EL display or a liquid crystal display.

An organic EL device has a structure in which a thin organic layer containing a fluorescent organic compound is sandwiched between a cathode forming an electron injection electrode and an anode forming a hole injection electrode, and electrons and holes are injected into the organic layer. In this display element, an exciton is generated by recombination, and display is performed using light emission (fluorescence / phosphorescence) when the exciton returns to the ground state.
There are several methods for producing a full-color organic EL display using an organic EL element, and the following are known as the full-color method.

  The method of patterning three types of EL elements that emit three colors of red, green, and blue in accordance with the pixels is highly efficient because the emitted light can be used as it is. However, there is a problem that the process of painting EL is complicated and it is difficult to increase the screen size because vapor deposition is performed using a metal mask, and it is necessary to make the life of each color uniform.

The EL element that emits blue light is made solid on the entire screen, and the red and green pixels have a color conversion layer that absorbs blue light and emits red and green fluorescence, respectively, and is patterned according to the pixels The method of full color using layers converts light of one color into other light, so that the light use efficiency is good, and the EL element does not require complicated painting.
However, in the case of this method, in the color conversion layer, it is necessary to suppress the dye concentration in the film to a certain amount or less so that the fluorescent dye contained in the film does not cause concentration quenching.

  In order to increase the light conversion efficiency while suppressing the dye concentration, it is necessary to increase the film thickness of the conversion layer, and the film thickness is generally about 10 μm. However, this film thickness is too thick for patterning by the photolithography method. Furthermore, in order to prevent the fluorescent dye of the color conversion layer from being excited by external light, it is necessary to further stack red and green color filters on the base of the color conversion layer. Therefore, there is a difficulty that the manufacturing process of the color conversion layer becomes complicated.

  The EL element emits white light, and the red, green, and blue color filters are superimposed on it to make it full color. Although there is an advantage that there is no color misregistration due to a change in EL with time, this method is inferior in light utilization efficiency to other full color methods because the white light source is changed to RGB. However, this method is attracting attention because of the cost of mass production and the ease of expansion to a larger screen.

Of the above-mentioned full color schemes for organic EL elements, the white light emitted by the EL elements is colored with red, green, and blue color filters, and the blue light emitted by the EL elements is converted into red and green. In general, the EL light emitting layer is laminated on a substrate on which a color filter layer or a color conversion layer is formed.
At this time, the unevenness of the step between the pixels of the patterned color filter layer and the color conversion layer, and the surface of the color filter layer and the color conversion layer, the surface of the surface of the color filter layer and the color conversion layer, breaks the electrode and the light emitting layer. In order to prevent this, an overcoat layer for smoothing the surface is often provided on the color filter layer or the color conversion layer.

  Furthermore, in order to prevent the organic EL element from deteriorating due to the influence of moisture contained in the binder resin of the overcoat layer, the color filter layer, and the color conversion layer, a barrier layer called a passivation layer is formed on the overcoat layer. It is often done. As the passivation layer, it is known that a silicon nitride or oxynitride film is mainly used, and this film is formed by a CVD method, a sputtering method or the like.

  By the way, when forming a passivation layer on the overcoat layer, if a minute foreign matter adheres to the surface of the overcoat layer, only the foreign matter portion at the time of film formation of the passivation layer is a part where the film formation is poor in a pinhole shape. From this, moisture contained in the color filter layer or the color conversion layer oozes out and damages this portion of the EL light emitting layer, resulting in a point-like non-light emitting portion called a dark spot.

  In order to prevent the generation of pinholes during the formation of the passivation layer, methods such as forming the passivation layer thickly or forming a plurality of layers have been performed. However, light absorption by the absorption of the passivation layer is performed. As the transmittance is reduced or the thickness of the passivation layer is increased, the stress of the film is increased and cracks are generated in the passivation layer.

Also, by devising the passivation layer creation process, it is possible to form a film successfully even if there are foreign objects on the overcoat layer. However, if the height of the foreign objects is high, the height of the passivation layer is only that part. Which adversely affects the electrode layer and the organic light-emitting layer formed by being laminated thereon. In particular, the organic light-emitting layer is widely formed by stacking a plurality of layers, but even if the plurality of layers are combined, the film thickness is a very thin layer of less than 0.5 μm.
For this reason, if the passivation layer has protrusions of about 1 μm, for example, the organic light emitting layer cannot be formed well and the electrodes are short-circuited.

  Liquid crystal displays, on the other hand, have two glass substrates with electrodes, alignment films, color filters, etc. formed on the surface, photo spacers formed on the substrate by photolithography or the like, or spacer beads that are sown on the substrate For example, the liquid crystal material is injected into the gap by bonding with an appropriate gap. In general, the gap (cell gap) formed by the two glass substrates is about 5 μm, but in recent years, the cell gap tends to become smaller as the image quality of the liquid crystal display increases.

By the way, if foreign matter exists on the color filter substrate, when the electrode made of the transparent conductive film is formed on the color filter substrate, the electrode is formed so that only that portion rises, and its height is higher than the cell gap. If it is large, it will come into contact with the counter electrode, causing a short circuit.
In addition, there is a liquid crystal panel method in which a transparent electrode is not formed on a color filter, such as an IPS method for driving a liquid crystal. However, even in this case, if a projection such as a foreign substance exists on the color filter, only that portion of liquid crystal molecules It will affect the orientation.

  In order to prevent the occurrence of defects when the liquid crystal panel or the organic EL panel as described above is produced, it is necessary to inspect the color filter substrate to eliminate the substrate on which foreign matter exists or to correct the defective portion.

In general, inspecting foreign matters and defects of a color filter is performed by placing a color filter substrate on a stage of an inspection apparatus and illuminating from a light source arranged above the substrate, or by arranging a light source below the substrate and transmitting illumination. The color filter substrate is photographed by moving the substrate from above or scanning the camera with a CCD camera or the like, image processing is performed, and defect portions are extracted from the photographed image to output as defect information.

  By the way, when the image of the color filter substrate is taken from right above the substrate as described above, if there is a foreign object or defect on the color filter substrate, even if the inspection apparatus can detect the foreign object or defect, Only the size can be recognized, and the size in the height direction cannot be recognized.

Therefore, in order to determine the defect in the height direction of the color filter substrate, first, after detecting a defect having a size larger than a certain value in the horizontal direction of the substrate by the above inspection, the substrate is reviewed and reviewed. It is necessary to measure the foreign matter or defect in the height direction for each foreign matter or defect detected at the time.
For the measurement in the height direction, it is possible to use a general surface measurement means such as a stylus type step gauge, a laser microscope, an interference microscope, an atomic force microscope, etc. The height must be measured at each location, which is very time consuming.

On the other hand, if all the defects on the color filter substrate recognized by the inspection apparatus are output in order to measure the height of the foreign matter or the depth of the defect by the above method, it is caused by noise in the optical detection element. The number of defects including the pseudo defects to be increased becomes enormous, and the height measurement at the time of review becomes more complicated.
Therefore, it is necessary to first set the size of the defect that must be detected by the inspection apparatus. In this case, if the horizontal size of the defect to be detected is set small, the number of defects that need to be height-measured at the time of review increases, and if the horizontal size of the defect to be detected is set large, the defect In spite of the small size in the horizontal direction, it is impossible to detect a foreign object or defect having a height.
JP 2003-315527 A JP-A-8-145849

  The present invention has been made in view of such a problem. For example, foreign matters and defects (pinholes) attached on an overcoat layer in an organic EL element, foreign matters and defects attached on a color filter substrate in a liquid crystal display. To provide a foreign matter and defect inspection apparatus capable of efficiently detecting foreign matter and defects (pinholes) such as (pinholes), heights of foreign matters, and depths of defects (pinholes). Let it be an issue.

The present invention provides an inspection apparatus for detecting foreign matter and defects attached on a substrate.
1) A light source that irradiates a substrate with incident light whose optical axis is inclined at an angle θ (0 ° <θ <20 °) with respect to the normal of the substrate, and the point at which the incident light is reflected by the substrate surface (P) A light source that focuses the incident light on a confocal plane corresponding to the pinhole below, perpendicular to the optical axis of the reflected light,
2) an objective lens having a confocal optical system arranged on the optical axis of the reflected light, which collects the reflected light from the substrate surface;
3) A point (P) where incident light is reflected on the substrate surface, and a pinhole disposed at an optically conjugate position,
4) an optical detection element that detects reflected light that has passed through the pinhole and is perpendicular to the optical axis of the reflected light;
5) A mechanism that moves the substrate in the x-axis direction or scans incident light with the direction in which the optical axis is inclined at an angle θ (0 ° <θ <20 °) with respect to the normal of the substrate as the x-axis direction,
A foreign matter and defect inspection apparatus.

In the foreign matter and defect inspection apparatus according to the present invention, the axis in the x-axis direction passing the point (P) where the incident light is reflected on the substrate surface is defined as the x-axis, and the point (P) on the substrate surface. Is the axis perpendicular to the x axis and the y axis.
1) Recognizing the peak (pk1) of the detection light appearing linearly in the y-axis direction on the detection surface of the optical detection element as the position on the substrate surface located at the point (P),
2) Recognize the peak of detection light (pk2) appearing in a point shape in the x-axis direction of the detection surface as a foreign substance or a defect,
3) Due to the movement of the substrate or the scan of incident light, the peak (pk2) of the detection light due to the reflected light from the foreign matter or defect changes to a defocused black point, and the black point is in the detection light peak (pk1). Recognize the position on the substrate surface of the foreign object or defect with the overlapping position,
4) When the detection light peak (pk2) is on the incident light side of the detection surface, the foreign object or defect is identified as a foreign object, and when it is on the reflected light side of the detection surface, the foreign object or defect is detected. A foreign matter and defect inspection apparatus comprising means for discriminating a defect and calculating the position of the foreign matter and the defect on the substrate surface.

In the foreign matter and defect inspection apparatus according to the present invention, the axis in the x-axis direction passing the point (P) where the incident light is reflected on the substrate surface is defined as the x-axis, and the point (P) on the substrate surface. Is the axis perpendicular to the x axis and the y axis.
1) The detection light peak (pk1) appearing linearly in the y-axis direction on the detection surface of the optical detection element is recognized as the position (Q) on the substrate surface located at the point (P),
2) Recognize the peak of detection light (pk2) appearing in a point shape in the x-axis direction of the detection surface as the position (R) of the foreign matter or defect,
3) Obtain the difference (L) between the position of the detection light peak (pk1) and the position of the detection light peak (pk2) on the detection surface,
4) The difference (M) between the position (Q) on the substrate surface and the position (R ′) of the foreign matter or defect is calculated by the following formula (1), and the difference (M) is calculated on the substrate surface. Recognizing the distance from the position (Q) to the position (R ') on the substrate surface of the foreign object or defect,
5) When the detection light peak (pk2) is on the incident light side of the detection surface, the foreign object or defect is identified as a foreign object, and when it is on the reflected light side of the detection surface, the foreign object or defect is detected. A foreign matter and defect inspection apparatus comprising means for discriminating a defect and calculating the position of the foreign matter and the defect on the substrate surface.
M = L · cos θ (1).

In the foreign matter and defect inspection apparatus according to the present invention, the axis in the x-axis direction passing the point (P) where the incident light is reflected on the substrate surface is defined as the x-axis, and the point (P) on the substrate surface. Is the axis perpendicular to the x axis and the y axis.
1) The detection light peak (pk1) appearing linearly in the y-axis direction on the detection surface of the optical detection element is recognized as the position (Q) on the substrate surface located at the point (P),
2) Recognize the peak of detection light (pk2) appearing in a point shape in the x-axis direction of the detection surface as the position (R) of the foreign matter or defect,
3) Obtain the difference (L) between the position of the detection light peak (pk1) and the position of the detection light peak (pk2) on the detection surface,
4) Calculate the difference in height (H) between the substrate surface and the top surface of the foreign substance or defect by the mathematical formula (2) shown below.
5) When the detection light peak (pk2) is on the incident light side of the detection surface, the foreign object or defect is identified as a foreign object, and the height difference (H) is given a plus sign to recognize the height of the foreign object. In addition, when it is on the reflected light side of the detection surface, the foreign object or the defect is identified as a defect, and the depth difference (H) is given a minus sign to recognize the depth of the defect,
A foreign matter and defect inspection apparatus comprising means for calculating a height of a foreign matter on a substrate surface and a depth of a defect on the substrate surface.
H = L · sin θ (2).

  In the foreign matter and defect inspection apparatus according to the present invention, the number of detected foreign matter and defects and the height / depth value calculated by the mathematical formula (2) satisfy a predetermined judgment formula. It is a foreign substance and defect inspection apparatus characterized by comprising means for determining whether or not.

  In the foreign matter and defect inspection apparatus according to the present invention, the detection surface of the optical detection element is moved when the substrate is moved or the incident light is scanned and the relative position between the substrate and the incident light is sequentially updated. When the position and intensity of the detection light peak (pk2) appearing in a dot shape in the x-axis direction change regularly with a certain period, there is provided means for determining that the change is a regular pattern of the substrate. This is a foreign matter and defect inspection apparatus.

  In the foreign matter and defect inspection apparatus according to the present invention, when the substrate is moved or the incident light is scanned, and the relative position between the substrate and the incident light is sequentially updated, the detection surface of the optical detection element is provided. When the detection light peak (pk1) appearing linearly in the y-axis direction shifts the detection surface in the x-axis direction in conjunction with the movement of the substrate or the scan of the incident light, the shift causes undulations on the substrate surface. A foreign matter and defect inspection apparatus characterized by comprising means for determining that there is a foreign object.

In the foreign matter and defect inspection apparatus according to the present invention, the detection light peak (pk1) shifts the detection surface in the x-axis direction in conjunction with the movement of the substrate or the scan of the incident light ( L ′)
1) The height (H ′) of the swell of the substrate surface is calculated by the following formula (3),
2) When the shift of the detection light peak (pk1) is on the incident light side of the detection surface, the direction of the undulation is identified as the upward direction of the substrate surface, and the detection light peak (pk1) starts to shift. Subtracting the height (H ′) from the height of the foreign matter calculated by the mathematical formula (2) before the calculation, and calculating the correct height of the foreign matter from the reference surface of the substrate,
When the shift of the detection light peak (pk1) is on the reflected light side of the detection surface, the direction of undulation is identified as the downward direction of the substrate surface, and before the detection light peak (pk1) starts shifting. A means for performing addition correction of the height (H ′) to the height value of the foreign matter calculated by the mathematical formula (2) and calculating a correct height of the foreign matter from the reference surface of the substrate. This is a foreign matter and defect inspection apparatus.
H ′ = L ′ · sin θ (3).

  The present invention is also the foreign matter and defect inspection apparatus according to the above invention, wherein the incident light is a laser beam.

  The present invention is also the foreign matter and defect inspection apparatus according to the above invention, wherein the laser beam is scanned within a visual field.

In the foreign matter and defect inspection apparatus according to the present invention, when the substrate is moved or the incident light is scanned, and the relative position between the substrate and the incident light is sequentially updated, the detection surface of the optical detection element is provided. When only the detection light peak (pk1) appearing linearly in the y-axis direction appears, and the defocused black spot of the foreign matter or defect overlaps the detection light peak (pk1),
1) If the black spot overlaps in the detection light peak (pk1) from the incident light side, the foreign matter or defect is identified as a foreign matter, and the black spot overlap in the detection light peak (pk1) is reflected. If from the light side, the foreign object or defect is identified as a defect,
2) Obtain the distance (L ″) from the position of the detection light peak (pk1) on the detection surface to the detection surface end (field end) in the x-axis direction on the incident light side, or detect on the detection surface Obtain the distance (L ′ ″) from the position of the light peak (pk1) to the detection surface end (field end) in the x-axis direction on the reflected light side,
3) The height (H ″) or the depth (H ′ ″) is calculated by the following formula (5) or formula (6),
4) a foreign matter characterized by comprising means for recognizing that the height of the foreign matter is higher than the height (H ″) or the depth of the defect is deeper than the depth (H ′ ″); It is a defect inspection device.
H ″ = L ″ · sin θ (4).
H ′ ″ = L ′ ″ · sin θ (5).

  Further, according to the present invention, in the foreign matter and defect inspection apparatus according to the above-described invention, when the substrate is replaced and another substrate is inspected, the intersection point between the other substrate surface on the stage and the confocal surface is optically measured before scanning. A foreign object characterized by comprising a mechanism for adjusting the distance between the detection optical system and the substrate, which is recognized by the detection surface of the detection element and matches the position of the intersection on the detection surface to a preset reference position of the detection surface. And a defect inspection apparatus.

  According to the present invention, in the foreign matter and defect inspection apparatus according to the above invention, when the substrate is moved or incident light is scanned, the peak of detection light that appears linearly in the y-axis direction on the detection surface of the optical detection element ( When the position of pk1) in the x-axis direction is displaced beyond a preset position range, the distance between the detection optical system and the substrate is adjusted to return the displacement to the preset position range. A foreign matter and defect inspection apparatus comprising a mechanism.

  In the foreign matter and defect inspection apparatus according to the present invention, when the substrate is moved or incident light is scanned, the height of the substrate surface is perpendicular to the direction in which the substrate is moved or incident light is scanned. If there is a location that changes rapidly, the location is set in advance so that the movement of the substrate or the scan of incident light is interrupted for each location, and the y-axis direction is detected on the detection surface of the optical detection element. The distance between the detection optical system and the substrate for resuming the movement of the substrate or scanning of the incident light by matching the position of the detection light peak (pk1) appearing linearly on the detection surface with the preset reference position of the detection surface It is a foreign matter and defect inspection apparatus characterized by comprising the adjustment mechanism.

  In the foreign matter and defect inspection apparatus according to the present invention, when the substrate is moved or incident light is scanned, the height of the substrate surface is parallel to the direction in which the substrate is moved or incident light is scanned. If there is a location that changes rapidly, the location is set in advance so that the movement of the substrate or the scan of incident light is interrupted for each location, and the y-axis direction is detected on the detection surface of the optical detection element. The distance between the detection optical system and the substrate for resuming the movement of the substrate or scanning of the incident light by matching the position of the detection light peak (pk1) appearing linearly on the detection surface with the preset reference position of the detection surface It is a foreign matter and defect inspection apparatus characterized by comprising the adjustment mechanism.

  According to another aspect of the present invention, there is provided a foreign matter and defect inspection apparatus comprising: means for setting an arbitrary portion of the substrate as a non-inspection region.

  The present invention is the foreign matter and defect inspection apparatus according to the above invention, wherein the substrate is a substrate for a flat panel display.

  The present invention is the foreign matter and defect inspection apparatus according to the above invention, wherein the substrate is a color filter substrate.

The present invention is a light source that irradiates a substrate with incident light whose optical axis is inclined at an angle θ (0 ° <θ <20 °) with respect to the normal line of the substrate, and the incident light is reflected by the substrate surface. At point (P), a light source that focuses the incident light on a confocal surface that is perpendicular to the optical axis of the reflected light and that corresponds to the following pinhole, and 2) collects the reflected light from the substrate surface. Objective lens having a confocal optical system arranged on the optical axis, 3) A point (P) where incident light is reflected by the substrate surface, and a pinhole arranged at an optically conjugate position, 4) Optical detection element that detects reflected light that has passed through the pinhole and is perpendicular to the optical axis of the reflected light. 5) Direction in which the optical axis is inclined at an angle θ (0 ° <θ <20 °) with respect to the normal of the substrate. Is a foreign matter and defect inspection apparatus equipped with a mechanism for moving the substrate in the x-axis direction or scanning the incident light. It becomes a foreign matter and defect inspection apparatus capable of efficiently detecting an object and a defect (pinhole), the height of the foreign matter, and the depth of the defect.

  In the foreign matter and defect inspection apparatus according to the present invention, the detection light peak (pk1) shifts the detection surface in the x-axis direction in conjunction with the movement of the substrate or the scan of the incident light (L ′). 1) Calculate the height (H ′) of the waviness of the substrate surface by the equation (3), and 2) When the shift of the peak (pk1) of the detection light is on the incident light side of the detection surface The direction of the undulation is identified as the upward direction of the substrate surface, and the height of the foreign matter calculated by the equation (2) before the peak (pk1) of the detection light starts to shift to the height ( H ′) is subtracted and the correct foreign object height from the reference surface of the substrate is calculated, and when the shift of the peak (pk1) of the detection light is on the reflected light side of the detection surface, the direction of waviness is Identifies the direction below the substrate surface, and the peak of detection light (pk1) shifts A means for performing addition correction of the height (H ′) on the height value of the foreign matter calculated by the mathematical formula (2) before starting to calculate the correct height of the foreign matter from the reference surface of the substrate; Therefore, even if there is undulation of the substrate itself in the actual substrate or undulation of the film thickness of the pattern formed on the substrate, the height value of the undulation in the z-axis direction is corrected to correct the foreign matter. It becomes possible to obtain the height accurately.

  Further, in the foreign matter and defect inspection apparatus, when the substrate is replaced and another substrate is inspected, the intersection of the other substrate surface on the stage and the confocal surface is determined before scanning. It has a mechanism for adjusting the distance between the detection optical system and the substrate, which is recognized by the detection surface and matches the position of the intersection on the detection surface with a preset reference position of the detection surface. When inspecting a substrate, even if there is a slight variation in the thickness of the substrate itself or the pattern formed on the substrate for each substrate, it is always independent of the variation in the z-axis direction for each substrate. Inspection can be performed with an optimal detection system.

  Further, according to the present invention, in the foreign matter and defect inspection apparatus, when the substrate is moved or incident light is scanned, the peak of detection light (pk1) appearing linearly in the y-axis direction on the detection surface of the optical detection element. When the position in the x-axis direction is displaced beyond a preset position range, a mechanism for adjusting the distance between the detection optical system and the substrate is provided to return the displacement to a preset position range. Therefore, the limit of the height of the detectable foreign matter or the depth of the defect (pinhole) is not reduced by the undulation in the substrate.

Hereinafter, the foreign matter and defect inspection apparatus according to the present invention will be described in detail.
FIG. 1 is a schematic diagram of a foreign matter and defect inspection apparatus according to the present invention. As shown in FIG. 1, the foreign matter and defect inspection apparatus inspects from a light source 101 whose optical axis is inclined by an angle θ (0 ° <θ <20 °) with respect to a normal line of a substrate 105 placed on a stage. And a mechanism for converging the reflected light 203 from the substrate 105 with the objective lens 102 having a confocal optical system disposed on the optical axis and detecting it with the optical detection element 104. ing.
The reflected light 203 passes through the pinhole 103 disposed at a position optically conjugate with the point P where the incident light 201 strikes the substrate, and reaches the optical detection element 104.

FIG. 2 is an enlarged schematic view of the visual field 106 of FIG. The surface 204 perpendicular to the reflected light 203 intersecting the substrate 105 at the point P across the objective lens 102 is optically conjugate (hereinafter, the surface 204 is referred to as a confocal surface).
Point P is an intersection of incident light 201a and reflected light 203a, that is, a point that regularly reflects incident light 201a as reflected light 203a when an object is present at this position.
Further, the incident light 201 from the light source is focused on the confocal plane 204. At this time, in the field of view 106 (FIG. 2), the confocal surface 204 is inclined toward the reflected light 203 side by θ with respect to the substrate surface 105, and the confocal surface 204 intersects the substrate surface 105 at a point P. Yes.

  In this case, the incident light 201a passing through the point P in the visual field 106 to be inspected by the incident light 201 is focused on the confocal plane 204, and the reflection reflected on the substrate 105 on the point P is reflected. The light 203 a is focused again on the pinhole 103 through the objective lens 102, passes through the pinhole 103, and is detected on the optical detection element 104.

  On the other hand, the light 201b and 201c that do not pass through the point P in the incident light 201 is in a defocused state on the substrate 105 that is a reflection surface, and the reflected light 203b and 203c of these lights is also defocused on the pinhole 103. Therefore, the reflected lights 203b and 203c are blocked by the pinhole 103 and are not detected by the optical detection element.

  Therefore, on the optical detection element 104, only the reflected light from the straight line (hereinafter referred to as the y-axis) orthogonal to the point P on the substrate surface at the point P is detected. Therefore, an image obtained by the optical detection element 104 is as shown in FIG. 3, and the detected intensity I distribution in the x-axis direction obtained on the y-axis is as shown in b in FIG.

  The inspection apparatus can scan at least in the x-axis direction. If a foreign object or a defect exists on the substrate 105 during the scan as shown in FIG. 4 (the substrate 105 is moved to the left side of the x-axis as indicated by a thick arrow in FIG. 4), When the upper surface of the foreign material 301 overlaps the confocal surface 204 at the position 31, the incident light 201 f applied to the foreign material 301 is focused on the foreign material. The reflected light 203 f passes through the pinhole 103 and is detected by the optical detection element 104.

As indicated by a in FIG. 5, the light detected on the optical detection element 104 at this time is reflected light 203 d from the y-axis orthogonal to the x-axis at the point P and reflected from the foreign substance 301 at the position 31. Light 203f. The detected intensity I distribution is as shown in FIG.
In FIG. 5, when the reflected light other than the reflected light 203d from the point P is on the incident light side on the detection surface of the optical detection element 104, the foreign object or defect is identified as a foreign object. The As will be described later, when the reflected light is on the reflected light side of the detection surface of the optical detection element 104, the foreign substance or defect is identified as a defect (pinhole). Further, since the optical detection element 104 is inclined by θ with respect to the substrate surface, the detected image is compressed by cos θ times in the x-axis direction.

  As shown in FIG. 6, when the substrate 105 is further moved to the position 32, the incident light 201 g applied to the foreign material 301 is degenerated on the foreign material 301 because the upper surface of the foreign material 301 is out of the confocal surface 204. The focus g is reached and the reflected light 203g is blocked by the pinhole 103 and is not detected by the optical detection element 104 as shown by a in FIG. That is, the optical detection element 104 can detect the top surface of the foreign material only when the top surface of the foreign material is on the confocal surface 204.

As shown in FIG. 8, when the substrate 105 is further moved in the x-axis direction (leftward in FIG. 7) from this state and the foreign object 301 reaches the position 33 which is the same position as the point P, the previous point P The reflected light from is lost. The reflected light from the point P (position 33) is defocused d by the foreign substance 301, passes through the objective lens 102 and the pinhole 103, and is not detected by the optical detection element 104. Therefore, as shown by a in FIG. 9, the foreign substance 301 is recognized as a defect in the y axis that has been detected so far on the detection surface. Therefore, the position of the detected foreign substance 301 on the substrate, that is, the position 33 shown in FIG. 9 can be recognized and output as the position of the foreign substance on the substrate.

As described above, the position where the upper surface of the foreign object is detected is the side where the incident light 201 exists (the right side in FIG. 5) with respect to the z axis passing through the point P, but this is the z axis as shown in FIG. On the other hand, when the detection is made at the position 34 on the side where the reflected light 203 exists (left side in FIG. 5), the confocal plane 204 exists at a position lower than the substrate 105 in the z-axis direction at the position 34. In such a case, the image detected on the optical detection element 104 is as indicated by a in FIG. 11, and the foreign matter or defect (pinhole) 304 detected at the position 34 is identified as a defect (pinhole). The
Further, the position 34 of the detected defect (pinhole) 304 can be calculated based on the position 33 shown in FIG.
The z-axis indicates an axis perpendicular to the surface formed by the x-axis and the y-axis on the intersection of the x-axis and the y-axis at the point P.

Further, as shown in FIG. 5, the light detected on the optical detection element 104, the reflected light 203d from the y-axis orthogonal to the x-axis at the point P, and the reflected light 203f from the foreign substance 301 at the position 31, It is possible to calculate the position of the foreign matter or defect on the substrate from the distance on the detection surface.
That is, as shown in FIG. 5, when the distance detected on the optical detection element is L and the distance on the substrate 105 (between QR ′) is M, the optical detection element 104 is also θ relative to the substrate 105. Therefore, L and M are in the relationship of Equation (1).
M = L · cos θ (1).

In addition, the area of the foreign matter is calculated based on the area of the detection light peak (pk2) appearing in a dotted manner on the detection surface other than the reflected light from the point P detected on the optical detection element 104 shown in FIG. Is possible.
Similarly, the area of the defect can be calculated from the area of the peak (pk2) of the detection light that appears in a dot shape on the detection surface other than the reflected light from the point P shown in FIG.

  That is, since the optical detection element 104 perpendicular to the optical axis 203 of the reflected light is inclined by θ with respect to the substrate 105, the area (S ′) detected in the x-axis direction of the detection surface of the optical detection element 104 is , Compressed by cos θ times in the x-axis direction. However, since θ is preferably about 7 ° to 5 °, the area (S) of the foreign matter or defect on the substrate can be regarded as S≈S ′ for convenience.

  Further, when the horizontal size of the foreign matter or defect is sufficiently large, the defect caused by the foreign matter or the defect may be larger than the width in the x-axis direction of the reflected light of the y axis detected by the optical detection element. In this case, since the substrate 105 is moving, the size of the defect is sequentially updated, and the area of the defect on the optical detection element 104 is obtained by superimposing the defect size in the moving direction.

In addition, when the foreign substance 301 on the substrate is moved together with the substrate in the x-axis direction, the vertex of the foreign substance can be recognized at the position 31. As shown in FIG. 5, the distance in the z-axis direction between the confocal surface 204 and the substrate 105 at the position 31, that is, the height H of the foreign matter is M at the distance between the position 31 and the point P (position 33) on the substrate. Therefore, the height H of the foreign substance is in the relationship of the following formula (6). If the distance between peaks detected by the optical detection element is L, the distance between H and L is as follows. The relationship represented by the mathematical formula (2) is obtained. Thereby, it is possible to calculate the height of the foreign matter.
H = M · tan θ (6).
H = L · sin θ (2).

  Similarly, as shown in FIG. 11, by giving a negative sign to the distance L, it is possible to calculate the depth of the defect (pinhole) by Equation 2.

  In the above case, the substrate 105 has been moved from the side where the incident light 201 exists with respect to the z axis to the side where the reflected light 203 exists (the left direction in FIG. 1) with respect to the z axis. Even if this is moved in the opposite direction, there is no problem.

  By calculating as described above, the position and area of the foreign matter on the substrate 105 on the substrate and the height of the foreign matter can be detected. In this case, the scan length is set from one end of the substrate 105 in the x-axis direction to the other end, and with respect to the y-axis direction, each time the scan in the x-axis direction ends once, the substrate 105 and the inspection optical system The entire position of the substrate 105 is inspected by updating the position in the y-axis direction and scanning again in the x-axis direction, or scanning using a plurality of inspection optical systems, or a combination of the two methods. It goes without saying that it is possible.

  Further, the position and the number of foreign objects detected, the area, the height of the foreign object are statistically determined, and the means and the determination result for determining whether or not the predetermined determination formula is satisfied with respect to the number of foreign objects, the area and the height If the output means is provided, it is possible to perform pass / fail judgment and to provide defect information of the substrate to the review machine and defect repair machine for the board that has been inspected, and the inspection can be performed efficiently. . Further, as the means for performing the determination, a widely used computer or the like can be used.

  When the substrate to be inspected is a color filter substrate or the like, an RGB pixel matrix, a photo spacer, or the like is formed on the substrate. In this case, regular height changes occur on the substrate surface. Therefore, when this substrate is scanned and inspected, regularly reflected light having a certain period is detected on the optical detection element, but the regular reflected light is detected in a regular pattern of the substrate. , The reflected light is not determined as a foreign object.

In the past, it has been assumed that the substrate 105 is geometrically flat without any particular limitation. However, the actual substrate has undulation of the substrate itself, undulation of the film thickness of the pattern formed on the substrate, etc. Exists. In such a case, since the distance of the surface of the substrate 105 with respect to the inspection optical system changes during scanning, the position of the intersection of the substrate 105 surface and the confocal surface 204 in the x-axis direction is shifted from the point P. .
That is, every time the position of the substrate is sequentially updated, the position of the intersection changes continuously. When the substrate 105 is moved and the relative position between the substrate 105 and the inspection optical system is sequentially updated, the position in the x-axis direction of the line intersecting the substrate 105 and the confocal plane 204 is continuously displaced according to the scan. In this case, it is possible to detect the undulation of the substrate by determining that the undulation is on the surface of the substrate.

  Originally, there is a certain amount of undulation in the film thickness of an actual substrate or a pattern formed on the substrate. If the undulation itself is small in height and the undulation slope is gentle, this will not cause defects such as a short circuit during panel creation. However, if the substrate has waviness, an error occurs when accurately obtaining the height of the foreign material existing on the substrate.

If the surface of the substrate 105 is flat and has no waviness, the light detected on the optical detection element 104 is reflected light from the y-axis orthogonal to the x-axis at the point P as shown in a in FIG. 203d and reflected light 203f from the foreign substance 301 at the position 31.
At this time, since the surface of the substrate 105 is flat, the position of the peak (pk1) of the detection light on the detection surface of the optical detection element 104 of the reflected light 203d from the point P is stationary even if the substrate is further moved. There is no shift in the x-axis direction.

On the other hand, when the surface of the substrate 105 has waviness, the substrate 105 is still a flat portion at the point P (position 37) as shown in FIG. The detected lights are the reflected light from the substrate 105 at the point P (position 37), that is, the detection light peak (pk1) and the detection light peak (pk3) reflected from the foreign material 305.
However, when the substrate 105 is moved in the left direction in FIG. 12 from the position 35 where the upper surface of the foreign material 305 is detected, the wavy portion indicated by the reference symbol U is shared before reaching the position 37 in FIG. It intersects with the focal plane 204.

Therefore, the position of the peak (pk1) of the detection light detected on the detection surface of the optical detection element 104 is from the original point P (position 37), that is, for example, from the center in the x-axis direction on the detection surface. Shifting starts in the right direction in FIG.
The time when the shift of the peak (pk1) of the detection light is stopped on the detection surface of the optical detection element 104 is continued, that is, the time when the swell is stabilized.

FIG. 12B shows that the shift of the detection light peak (pk1) at the position 36 on the detection surface of the optical detection element 104 has stopped. If the shift amount of the peak from the detection light peak (pk1) at the position 37 to the detection light peak (pk1) at the position 36 is L ′ on the detection surface of the optical detection element 104, the calculation is performed at the position 36. The height is deviated by the height H ′ obtained by the following formula (3).
H ′ = L ′ · sin θ (3).

When the position 36 in FIG. 12B is shifted to the incident light side (right side in FIG. 12) with respect to the point P (position 37), the undulation is higher in the z-axis direction, and conversely, the reflected light side (FIG. 12). When shifted to the middle left), the undulation is lowered in the z-axis direction.
According to the present invention, since the value of the height of the undulation in the z-axis direction can be corrected, the height of the foreign matter can be accurately obtained even when the undulation is present on the substrate.

  The light source used in the present invention is not particularly limited as long as it is a light source applicable to the optical system of the present invention, but laser light for scanning from the point of resolution is preferable. As a means for scanning the laser light, a galvanometer mirror, a polygon mirror, an acoustooptic device, or the like can be used.

In the present invention, the inspection optical system has a finite field of view. However, as shown in FIG. 13 (a), the foreign object 306 at a position 28 that is the detection surface end (field end) with respect to the x-axis direction of the field 106. When the height H36 of the foreign material 306 is present, the value H calculated by the equation (4) based on the distance L ″ in the x-axis direction between the point P (position 25) and the detection surface 28 When the height is higher than ″ (H36> H ″), the top surface of the foreign material 306 does not intersect the confocal surface 204 even if the foreign material 306 is moved from the position 28 to the point P (position 25) and scanned from the position 29. Therefore, the upper surface of the foreign material 306 is not detected by the optical detection element 104.
H ″ = L ″ · sin θ (4).

Similarly, when the defect (pinhole) 307 arrives at the position 29, the calculation is performed by Expression (6) based on the distance L ″ ′ in the x-axis direction between the position 29 and the point P (position 25) on the detection surface. When the depth H37 of the defect (pinhole) 307 is deeper than the value H ′ ″, the bottom surface of the defect (pinhole) 307 is scanned from the position 28 to the point P (position 25) and the position 29. Since it does not intersect with the focal plane 204, the bottom surface of the defect (pinhole) is not detected by the optical detection element 104.
H ′ ″ = L ′ ″ · sin θ (5).

However, as shown in FIG. 13B, when the foreign matter 306 or the defect (pinhole) 307 comes to the position of the point P (position 25), it is normally reflected at the point P (position 25) and is reflected on the optical detection element 104. The line of reflected light that should be detected in this way is blocked by the foreign matter 306 or the defect (pinhole) 307, so the presence of the foreign matter 306 or the defect (pinhole) 307 is detected at the point P (position 25) at that time. It is possible.
In the present invention, the amount of movement of the substrate 105 until a black spot due to defocusing of a foreign substance or a defect is detected in the detection light peak (pk1) of the detection surface of the optical detection element 104 shown in FIG. That is, it is determined that there is a foreign object having a height of H ″ ″ or more or a defect (pinhole) having a depth of H ″ ″ or more depending on the distance from both ends of the visual field of the detection surface. It is possible to do.

  The inspection apparatus provided by the present invention can inspect a plurality of substrates by replacing the inspection substrate, but even a substrate created with the same specifications is formed on the substrate itself or on each substrate. There is a slight variation in the thickness of the formed pattern. Therefore, according to the present invention, the intersection of the substrate 105 and the confocal plane 204 shown in FIG. 2 set on the stage is recognized before scanning, and the position of the intersection is a preset reference position in the field of view. A mechanism capable of changing the distance between the optical detection system and the substrate 105 so as to meet the above requirements.

  For this reason, the inspection machine provided by the present invention can always inspect with an optimal detection system regardless of variations in the z-axis direction for each substrate. As a method capable of changing the distance between the optical detection system and the substrate 105, a detection unit including a light source 101, an objective lens 102 for detecting reflected light, a pinhole 103, and an optical detection element 104 may include a piezoelectric element or the like. There is a method of providing a drive mechanism using a ball screw or the like, but the method is not limited to this.

  The above-described undulation in the substrate causes a change in the position in the x-axis direction of the intersection between the substrate 105 and the focal plane 204. However, if the displacement is large, the distance from the intersection to the edge of the field of view on the detection surface is shortened. That is, the limit of the height of the detectable foreign matter or the limit of the depth of the pinhole is reduced. Therefore, according to the present invention, when the position of the intersection of the substrate 105 and the focal plane 204 in the x-axis direction changes beyond the preset position range, the displacement is set to the reference position set first. A mechanism capable of changing the distance between the optical detection system and the substrate 105 so as to return is provided.

  In this case, when the position in the x-axis direction of the intersection of the substrate 105 and the focal plane 204 changes so as to exceed the set range, feedback is performed so as to return to the initially set reference position. The same mechanism as described above can be used as a method for changing the distance between the optical detection system and the substrate 105.

  Further, the substrate to be inspected is usually subjected to some patterning, and depending on the specification of the substrate to be inspected, the height of the substrate surface differs between the part of the substrate surface that is patterned and the part of the substrate surface that is not patterned. Therefore, according to the present invention, as shown in FIG. 14, the height of the surface of the substrate is perpendicular to the scanning direction at the boundary portion 108 of the pattern portion 107 on the substrate 105 in the direction perpendicular to the scanning direction. In a place that changes rapidly in a certain direction, at a preset position, the distance between the optical detection system and the substrate 105 is changed so that the position of the intersection point matches the preset reference position of the detection surface, A mechanism is provided for re-adjusting the distance between the detection optical system and the substrate to be inspected so that the position of the intersection of the substrate 105 and the confocal surface 204 appears at an appropriate location on the detection surface, and restarting scanning. As a result, it is possible to always perform inspection under optimum conditions regardless of the pattern. The same mechanism as described above can be used as a method for changing the distance between the optical detection system and the substrate 105.

Further, as shown in FIG. 15, the position of the intersection of the substrate 105 and the confocal surface 204 is different on the detection surface even in the boundary portion 109 in the direction parallel to the scanning direction of the patterning unit 107. In this case, according to the present invention, for the portions having different heights, the distance between the optical detection system and the substrate 105 is set so that only the portion matches the position of the intersection with the preset reference position of the detection surface. It has a mechanism for changing the distance between the detection optical system and the substrate to be inspected again so that the position of the intersection of the substrate 105 and the confocal plane 204 appears at an appropriate place on the detection surface. ing. As a result, it is possible to always perform inspection under optimum conditions regardless of the pattern. The same mechanism as described above can be used as a method for changing the distance between the optical detection system and the substrate 105.

  The substrate to be inspected usually has an irregular pattern such as an alignment mark in addition to a regular pattern such as a pixel matrix. According to the present invention, in this case, in order to prevent an irregular pattern from being recognized as a defect of the substrate by scanning the substrate, a portion having an irregular pattern in the substrate is arbitrarily set in the inspection apparatus in advance. In addition, the setting portion has a mechanism that does not perform inspection determination. Thereby, an irregular pattern is not recognized as a defect.

  The inspection apparatus provided by the present invention is suitable for inspection of foreign matters or defects on a substrate for a flat panel display, is suitable for inspection of a color filter substrate, and further, is used for a color filter substrate for a liquid crystal display or an organic EL. It is suitable for inspection of a color filter substrate for display.

It is a schematic diagram of the foreign material and defect inspection apparatus by this invention. It is the schematic diagram which expanded the visual field in FIG. It is an image obtained with the optical detection element of the reflected light in FIG. It is a schematic diagram which shows a mode that the foreign material on a board | substrate reflects incident light. It is explanatory drawing of the reflected light from the board | substrate in P point, the reflected light from a foreign material, the image obtained by an optical detection element, and detection intensity distribution. It is explanatory drawing which shows a mode that the upper surface of the foreign material remove | deviated from the confocal surface. 7 is an image obtained by the optical detection element at a position shown in FIG. It is explanatory drawing which showed a mode that it does not reflect from the upper surface of a foreign material, when the position of a foreign material is P point. FIG. 9 is an image obtained by the optical detection element at a position shown in FIG. It is a schematic diagram which shows a mode that the defect (pinhole) on a board | substrate reflects incident light. FIG. 11 shows an image obtained by the optical detection element at a position shown in FIG. 10 where a defect (pinhole) is present. (A) is explanatory drawing of the image and detection intensity distribution which are obtained with an optical detection element before a wave | undulation reaches | attains P point. (B) is an explanatory diagram of an image obtained by the optical detection element and the detected intensity distribution when the undulation reaches the point P. (A) is explanatory drawing which shows a mode that reflected light is not obtained when the height of a foreign material is higher than the height which can be detected by a visual field edge part. (B) is an explanatory view showing a state where a black spot is obtained when the point P is reached when the height of the foreign object is higher than the height that can be detected at the edge of the visual field. It is explanatory drawing which shows the location where the height of a substrate surface changes rapidly in the boundary part of the direction perpendicular | vertical to a scanning direction of the pattern part on a board | substrate. It is explanatory drawing which shows the location where the height of a substrate surface changes rapidly in the boundary part of the direction parallel to a scanning direction of the pattern part on a board | substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Light source 102 ... Objective lens 103 ... Pinhole 104 ... Optical detection element 105 ... Substrate 106 ... Field of view 107 ... Pattern part 108, 109 ... Boundary part 201- .... Incident light 203 ... Reflected light 204 ... Confocal surfaces 301, 305, 306 ... Foreign matter 304, 307 ... Defect (pinhole)
H, H36 ... Foreign object height H37 ... Defect (pinhole) depth H '... Waviness height L ... Distance M detected on optical detection element ... On substrate The distance P at the point P ... The point U that regularly reflects the incident light as reflected light when there is an object ... The wave portion a ... The image b obtained with the optical detection element ... The detection intensity obtained with the optical detection element Distributions d, g, defocus pk1, detection light peaks pk2, pk3, which appear linearly in the y-axis direction on the detection surface, and detection lights, which appear in the form of dots in the x-axis direction on the detection surface peak

Claims (18)

In the inspection device that detects foreign matter and defects attached on the substrate,
1) A light source that irradiates a substrate with incident light whose optical axis is inclined at an angle θ (0 ° <θ <20 °) with respect to the normal of the substrate, and the point at which the incident light is reflected by the substrate surface (P) A light source that focuses the incident light on a confocal plane corresponding to the pinhole below, perpendicular to the optical axis of the reflected light,
2) an objective lens having a confocal optical system arranged on the optical axis of the reflected light, which collects the reflected light from the substrate surface;
3) A point (P) where incident light is reflected on the substrate surface, and a pinhole disposed at an optically conjugate position,
4) an optical detection element that detects reflected light that has passed through the pinhole and is perpendicular to the optical axis of the reflected light;
5) A mechanism that moves the substrate in the x-axis direction or scans incident light with the direction in which the optical axis is inclined at an angle θ (0 ° <θ <20 °) with respect to the normal of the substrate as the x-axis direction,
A foreign matter and defect inspection apparatus characterized by comprising: When the axis in the x-axis direction passing through the point (P) where the incident light is reflected by the substrate surface is the x-axis, and the axis perpendicular to the x-axis on the substrate surface at the point (P) is the y-axis,
1) Recognizing the peak (pk1) of the detection light appearing linearly in the y-axis direction on the detection surface of the optical detection element as the position on the substrate surface located at the point (P),
2) Recognize the peak of detection light (pk2) appearing in a point shape in the x-axis direction of the detection surface as a foreign substance or a defect,
3) Due to the movement of the substrate or the scan of incident light, the peak (pk2) of the detection light due to the reflected light from the foreign matter or defect changes to a defocused black point, and the black point is in the detection light peak (pk1). Recognize the position on the substrate surface of the foreign object or defect with the overlapping position,
4) When the detection light peak (pk2) is on the incident light side of the detection surface, the foreign object or defect is identified as a foreign object, and when it is on the reflected light side of the detection surface, the foreign object or defect is detected. 2. The foreign matter and defect inspection apparatus according to claim 1, further comprising means for identifying the defect and calculating the position of the foreign matter and the defect on the substrate surface. When the axis in the x-axis direction passing through the point (P) where the incident light is reflected by the substrate surface is the x-axis, and the axis perpendicular to the x-axis on the substrate surface at the point (P) is the y-axis,
1) The detection light peak (pk1) appearing linearly in the y-axis direction on the detection surface of the optical detection element is recognized as the position (Q) on the substrate surface located at the point (P),
2) Recognize the peak of detection light (pk2) appearing in a point shape in the x-axis direction of the detection surface as the position (R) of the foreign matter or defect,
3) Obtain the difference (L) between the position of the detection light peak (pk1) and the position of the detection light peak (pk2) on the detection surface,
4) The difference (M) between the position (Q) on the substrate surface and the position (R ′) of the foreign matter or defect is calculated by the following formula (1), and the difference (M) is calculated on the substrate surface. Recognizing the distance from the position (Q) to the position (R ') on the substrate surface of the foreign object or defect,
5) When the detection light peak (pk2) is on the incident light side of the detection surface, the foreign object or defect is identified as a foreign object, and when it is on the reflected light side of the detection surface, the foreign object or defect is detected. 2. The foreign matter and defect inspection apparatus according to claim 1, further comprising means for identifying the defect and calculating the position of the foreign matter and the defect on the substrate surface.
M = L · cos θ (1) When the axis in the x-axis direction passing through the point (P) where the incident light is reflected by the substrate surface is the x-axis, and the axis perpendicular to the x-axis on the substrate surface at the point (P) is the y-axis,
1) The detection light peak (pk1) appearing linearly in the y-axis direction on the detection surface of the optical detection element is recognized as the position (Q) on the substrate surface located at the point (P),
2) Recognize the peak of detection light (pk2) appearing in a point shape in the x-axis direction of the detection surface as the position (R) of the foreign matter or defect,
3) Obtain the difference (L) between the position of the detection light peak (pk1) and the position of the detection light peak (pk2) on the detection surface,
4) Calculate the difference in height (H) between the substrate surface and the top surface of the foreign substance or defect by the mathematical formula (2) shown below.
5) When the detection light peak (pk2) is on the incident light side of the detection surface, the foreign object or defect is identified as a foreign object, and the height difference (H) is given a plus sign to recognize the height of the foreign object. In addition, when it is on the reflected light side of the detection surface, the foreign object or the defect is identified as a defect, and the depth difference (H) is given a minus sign to recognize the depth of the defect,
4. The foreign matter and defect inspection apparatus according to claim 1, further comprising means for calculating a height of the foreign matter on the substrate surface and a depth of the defect on the substrate surface.
H = L · sinθ (2)   A means for determining whether or not the number of detected foreign matters and defects and the height / depth value calculated by the mathematical formula (2) satisfy a predetermined judgment formula is provided. The foreign matter and defect inspection apparatus according to any one of claims 1 to 4.   When the substrate is moved or incident light is scanned and the relative position between the substrate and the incident light is sequentially updated, the peak of detection light (pk2) appearing in a dot shape in the x-axis direction of the detection surface of the optical detection element 6. The apparatus according to claim 1, further comprising means for determining that the position and intensity of the substrate regularly change with a certain period as a regular pattern of the substrate. Foreign matter and defect inspection apparatus as described in the paragraph   The peak of detection light (pk1) that appears linearly in the y-axis direction on the detection surface of the optical detection element when the substrate is moved or the incident light is scanned and the relative position between the substrate and the incident light is sequentially updated. 2. When the detection surface is shifted in the x-axis direction in conjunction with the movement of the substrate or the scan of incident light, there is provided means for determining that the shift is the undulation of the substrate surface. The foreign matter and defect inspection apparatus according to claim 6. The peak (pk1) of the detection light determines the shift distance (L ′) obtained by shifting the detection surface in the x-axis direction in conjunction with the movement of the substrate or the scan of incident light,
1) The height (H ′) of the swell of the substrate surface is calculated by the following formula (3),
2) When the shift of the detection light peak (pk1) is on the incident light side of the detection surface, the direction of the undulation is identified as the upward direction of the substrate surface, and the detection light peak (pk1) starts to shift. Subtracting the height (H ′) from the height of the foreign matter calculated by the mathematical formula (2) before the calculation, and calculating the correct height of the foreign matter from the reference surface of the substrate,
When the shift of the detection light peak (pk1) is on the reflected light side of the detection surface, the direction of undulation is identified as the downward direction of the substrate surface, and before the detection light peak (pk1) starts shifting. A means for performing addition correction of the height (H ′) to the height value of the foreign matter calculated by the mathematical formula (2) and calculating a correct height of the foreign matter from the reference surface of the substrate. The foreign matter and defect inspection apparatus according to claim 7, wherein
H ′ = L ′ · sin θ (3)   The foreign matter and defect inspection apparatus according to claim 1, wherein the incident light is laser light.   The foreign matter and defect inspection apparatus according to claim 9, wherein the laser beam is scanned within a visual field. When the substrate is moved or the incident light is scanned and the relative position between the substrate and the incident light is sequentially updated, the peak of detection light (pk1) appearing linearly in the y-axis direction on the detection surface of the optical detection element Only, and the defocused black spot of the foreign object or defect overlaps the peak (pk1) of the detection light,
1) If the black spot overlaps in the detection light peak (pk1) from the incident light side, the foreign matter or defect is identified as a foreign matter, and the black spot overlap in the detection light peak (pk1) is reflected. If from the light side, the foreign object or defect is identified as a defect,
2) Obtain the distance (L ″) from the position of the detection light peak (pk1) on the detection surface to the detection surface end (field end) in the x-axis direction on the incident light side, or detect on the detection surface Obtain the distance (L ′ ″) from the position of the light peak (pk1) to the detection surface end (field end) in the x-axis direction on the reflected light side,
3) Calculate the height (H ″) or the depth (H ′ ″) by the following formula (4) or formula (5),
4) A means for recognizing that the height of the foreign matter is higher than the height (H ″) or the depth of the defect is deeper than the depth (H ′ ″) is provided. The foreign matter and defect inspection apparatus according to any one of claims 1 to 10.
H ″ = L ″ · sin θ (4)
H '''=L''' · sin θ (5)   When performing inspection of another substrate by replacing the substrate, before scanning, the intersection of another substrate surface on the stage and the confocal surface is recognized by the detection surface of the optical detection element, The foreign object according to any one of claims 1 to 11, further comprising a mechanism for adjusting a distance between the detection optical system and the substrate, the position of which is adjusted to a preset reference position of the detection surface. Defect inspection equipment.   The position in the x-axis direction of the peak (pk1) of the detection light that appears linearly in the y-axis direction on the detection surface of the optical detection element when moving the substrate or scanning the incident light is a preset position range. 13. A mechanism for adjusting the distance between the detection optical system and the substrate is provided to return the displacement to a preset position range when the displacement is exceeded. The foreign matter and defect inspection apparatus according to any one of the above.   When moving the substrate or scanning incident light, if there is a portion where the height of the substrate surface changes abruptly in a direction perpendicular to the direction of moving the substrate or scanning incident light, the portion is By setting, the movement of the substrate or the scan of incident light is interrupted for each location, and the detection surface of the detection light peak (pk1) appearing linearly in the y-axis direction on the detection surface of the optical detection element A mechanism for adjusting the distance between the detection optical system and the substrate, wherein the position of the detection optical system is matched with a preset reference position of the detection surface and the movement of the substrate or scanning of incident light is resumed, is provided. Item 14. The foreign matter and defect inspection device according to any one of Items 13 to 14.   When moving the substrate or scanning incident light, if there is a place where the height of the substrate surface changes suddenly in a direction parallel to the direction of moving the substrate or scanning incident light, the position is previously determined. By setting, the movement of the substrate or the scan of incident light is interrupted for each location, and the detection surface of the detection light peak (pk1) appearing linearly in the y-axis direction on the detection surface of the optical detection element A mechanism for adjusting the distance between the detection optical system and the substrate, wherein the position of the detection optical system is matched with a preset reference position of the detection surface and the movement of the substrate or scanning of incident light is resumed, is provided. Item 15. The foreign matter and defect inspection device according to any one of Items 14 to 14.   The foreign matter and defect inspection apparatus according to claim 1, further comprising a unit that sets an arbitrary portion of the substrate as a non-inspection region. The foreign substance and defect inspection device according to claim 1, wherein the substrate is a substrate for a flat panel display.   The foreign substance and defect inspection apparatus according to claim 1, wherein the substrate is a color filter substrate.

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