TWI668438B - Substrate inspection device and method - Google Patents

Abstract

The present invention provides an apparatus and method for a laminated substrate and a coated substrate having a surface coated or sealed, even if foreign matter or contaminants are attached to the surface or back surface of the laminated substrate. It is detected, and the inside of the multi-layer substrate can be specifically inspected.

The present invention relates to a substrate inspection apparatus that inspects an inside of a multi-layer substrate, and includes an imaging unit, a reflection illumination unit, a reflection illumination switching unit, a transmission illumination unit, a switching reflection illumination unit, and/or an illumination direction through the illumination unit. A switching unit, a foreign matter detecting unit, and a difference processing unit.

Description

Substrate inspection device and method

The present invention relates to a substrate inspection apparatus and method for detecting foreign matter immersed in a bonded substrate and a substrate coated or sealed on the surface (ie, a multi-layer substrate), or checking whether the internal structure is of a specific size and shape Form, or check whether bubbles or the like are mixed at the laminate interface.

Since the prior art, it has been known that a part having a fine movable portion (for example, a sensor, a gyroscope, a micro-relay, etc.) is formed by a wafer or the like to form a laminated structure such as a MEMS (Micro Electro Mechanical Systems). Technology (for example, Patent Document 1).

Further, there has been proposed a technique of inspecting foreign matter of a specific layer (functional layer or the like) which is immersed in such a substrate (for example, Patent Document 2).

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2010-69599

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2014-126436

In a laminated structure such as MEMS, there are many cavities or gaps inside, and particularly when foreign matter is present in a portion narrower than the gap between adjacent structures, the movement of the fine movable portion is hindered, and the desired performance is not exhibited. After that.

However, in the technique of Patent Document 2, the illumination of the transparent type is used to align the specific layer inside the bonded substrate to perform the foreign matter inspection, but when foreign matter or contamination is attached to the surface or the back surface of the packaged substrate. When the object is the same, it is determined that there is a foreign matter or the like even if it is removable later.

Accordingly, it is an object of the present invention to provide an apparatus and method for a bonded substrate and a coated or sealed multi-layer substrate, even if foreign matter or contaminants are attached to the surface or back surface of the multi-layer substrate. The inside of the multi-layer substrate can be inspected specifically.

In order to solve the above problems, an aspect of the present invention is a substrate inspection apparatus that inspects an inside of a multi-layer substrate, and includes an imaging unit that images an inspection target area set on the multi-layer substrate; An illumination unit that emits infrared light or visible light from the imaging unit side toward the inspection target area; and a reflection illumination switching unit that switches between the infrared illumination and the visible light from the reflective illumination unit; and the illumination unit is Irradiating the inspection target area with the infrared light on the side opposite to the imaging unit; and switching the illumination direction switching unit to use either or both of the reflection illumination unit and/or the transmission illumination unit; and the foreign object detection unit The foreign matter existing in the inspection target region is detected based on the image captured by the imaging unit, and the difference processing unit performs the detection based on the foreign matter detection result based on the image captured by the infrared light. The difference processing of the foreign object detection result of the image of the camera.

Moreover, another aspect of the present invention is a substrate inspection method, which is an inspection method. The inside of the multi-layer substrate includes: an imaging step by infrared reflected light, which irradiates infrared light to an inspection target region set on the multi-layer substrate, and images the light reflected from the inspection target region; a first main surface imaging step of the visible light, wherein the visible light is emitted from the first main surface side of the multi-layer substrate toward the inspection target region, and the light reflected from the inspection target region is imaged; a step of inverting the front and back sides of the layer substrate; and a second principal surface image capturing step by visible reflected light, wherein the visible light is emitted from the second main surface side of the multi-layer substrate toward the inspection target region, and the inspection is performed from the inspection Light imaging of the target area reflection; and an image obtained based on the first main surface imaging step by visible reflected light based on an inspection result of the image obtained by the imaging step by the infrared reflected light The inspection result and the step of performing differential processing based on the inspection result of the image obtained by the second main surface imaging step by the visible reflected light.

Moreover, another aspect of the present invention is a substrate inspection method for inspecting an inside of a multi-layer substrate, and comprising: an imaging step by infrared transmission light, which is set toward the multi-layer substrate The inspection target area is irradiated with infrared light, and the light passing through the inspection target area is imaged; and the first main surface imaging step by visible reflected light is performed from the first main surface side of the multi-layer substrate toward the inspection target area a step of irradiating the visible light to the light reflected from the inspection target region; a step of inverting the front and back surfaces of the multi-layer substrate; and a second main surface imaging step by visible reflected light from the multi-layer substrate The second main surface side irradiates the inspection target area with visible light, and images the light reflected from the inspection target area; and the image obtained based on the imaging step by the infrared transmitted light. The result of the inspection is performed on the inspection result based on the image obtained by the first main surface imaging step by the visible reflected light and the inspection result based on the image obtained by the second main surface imaging step by the visible reflected light. The steps of differential processing.

Moreover, another aspect of the present invention is a substrate inspection method for inspecting an inside of a multi-layer substrate, and comprising: an imaging step by infrared reflection light and infrared transmission light, wherein the alignment is set to the above The inspection target region of the multi-layer substrate is irradiated with infrared light, and the light reflected from the inspection target region and the light passing through the inspection target region are imaged; and the first main surface imaging step by visible reflected light is performed from the above-mentioned complex The first main surface side of the layer substrate is irradiated with visible light toward the inspection target region, and the light reflected from the inspection target region is imaged; the step of inverting the front and back surfaces of the multilayer substrate; and the second step by visible reflected light a main surface imaging step of irradiating visible light from the second main surface side of the multi-layer substrate toward the inspection target region, and capturing light reflected from the inspection target region; and based on the infrared transmission light and infrared The result of the inspection of the image obtained by the imaging step of the reflected light, and the result of the inspection based on the image obtained by the first main surface imaging step by the visible reflected light Check images acquired by the main surface of the second imaging step of visible light is reflected results of the processing step difference.

An object of the present invention is to provide an apparatus and method for a multi-layer substrate that does not detect foreign matter, contaminants, or the like on the surface or back surface of the multi-layer substrate. The interior is specially inspected.

1‧‧‧Substrate inspection device

1f‧‧‧ device framework

2‧‧‧Substrate retention department

3‧‧‧Photography Department

4‧‧‧Lighting Department

5‧‧‧Inspection Department

20‧‧‧ mounting table

20h‧‧‧ openings

21‧‧‧X-axis slides

22‧‧‧Y-axis slide

23‧‧‧Rotating mechanism

24‧‧‧Connected components

30‧‧‧Mirror tube

31‧‧‧ half mirror

32‧‧‧Lights that shine upwards

33‧‧‧Mirror tube

34‧‧‧ Objective lens

34a‧‧‧ objective lens

34b‧‧‧ objective lens

35‧‧‧ camera camera

36‧‧‧Light-receiving components

41‧‧‧Coaxial Epi-Illumination Department

41a‧‧‧Huan Light Source Department

41b‧‧ ‧Shutter Department

41c‧‧‧Filter Department

41d‧‧‧Filter switching unit

41f‧‧‧Fiber Department

41L‧‧‧Lights

42‧‧‧Lifted light

43‧‧‧Transmission Department

43a‧‧‧Halogen source department

43b‧‧ ‧Shutter Department

43c‧‧‧Filter Department

43d‧‧‧Filter switching unit

43e‧‧·Mirror

43f‧‧‧Fiber Department

43L‧‧‧Lights

44‧‧‧Lighting direction switching section

45‧‧‧ oblique lighting department

45L‧‧‧ illumination light

46‧‧‧Lighting direction switching section

51‧‧‧ Foreign Body Detection Department

52‧‧‧Differential Processing Department

G‧‧‧Internal structures

R‧‧‧ inspection area

Side of the S1‧‧ ‧ layered substrate (surface)

S2‧‧‧ the other side of the multi-layer substrate (back)

W‧‧‧Multilayer substrate

X1‧‧‧ foreign objects that should be detected

X2‧‧‧ foreign objects that should be detected

X3‧‧‧ foreign objects that should be detected

X‧‧‧ directions

Y1‧‧‧Do not want to detect foreign objects

Y2‧‧‧ unwanted foreign objects detected

Y‧‧‧ direction

Z‧‧‧direction

Θ‧‧‧ direction

FIGS. 1(a) and 1(b) are schematic diagrams showing an example of a multi-layer substrate to be inspected.

Fig. 2 is a schematic view showing an example of a form in which the present invention is embodied.

Fig. 3 is a flow chart showing an example of imaging and inspection of a multi-layer substrate by applying the present invention.

4(a) to 4(g) are plan views showing an example of imaging and inspection of a multi-layer substrate inspected by applying the present invention.

Fig. 5 is a plan view showing another example of the case where the multi-layer substrate inspected by applying the present invention is imaged and inspected.

Fig. 6 is a plan view showing still another example of the case where the multi-layer substrate inspected by applying the present invention is imaged and inspected.

Fig. 7 is a flow chart showing another example of imaging and inspection of a multi-layer substrate by applying the present invention.

The form for carrying out the invention will be described using the drawings. In each of the figures, the three axes of the orthogonal coordinate system are set to X, Y, and Z, and the XY plane is set to a horizontal plane, and the Z direction is set to a vertical direction. In particular, the Z direction sets the direction of the arrow symbol to the upper direction and the reverse direction to the lower direction.

A person who has a comb-shaped minute cantilever beam formed in the inside of the multi-layer substrate (hereinafter simply referred to as "multilayer substrate W") is exemplified as an object to be inspected. The multi-layer substrate W is formed by molding the inner structure by processing the surface of the crucible wafer, and then cap-sealing the substrate including the glass or the crucible from the upper surface side to form a so-called hollow structure. The surface on one side of the multi-layer substrate W is referred to as a first main surface (or simply referred to as "surface") S1. Further, the other side having the positive and negative relationship with the surface is referred to as a second main surface (or simply referred to as "back surface") S2.

Fig. 1 is a schematic view showing an example of a multi-layer substrate to be inspected, and a cross-sectional view is shown in Fig. 1(a), and a plan view is shown in Fig. 1(b). Further, in Fig. 1 (a) and (b), the multi-layer substrate W having the internal structure G, the foreign matter existing in the inside (i.e., the foreign matter to be detected) X1 to X3, and the adhesion to the multi-layer substrate W are respectively shown. The foreign matter on the surface S1 or the back surface S2 (that is, the foreign matter that is not desired to be detected) Y1, Y2. Further, in the multi-layer substrate W, the inspection target region R is indicated by a broken line.

Fig. 2 is a conceptual diagram showing an example of a form in which the present invention is embodied, and a composite diagram showing a schematic diagram of a device used for obtaining an image of an inspection target region and a configuration necessary for inspection based on the acquired image are described. Block diagram.

The substrate inspection apparatus 1 embodying the present invention detects foreign matter that has entered the inside of the multi-layer substrate W, or checks whether the internal structure is formed in a specific size or shape, or checks whether air bubbles or the like are mixed in the laminate interface. The substrate inspection device 1 includes a substrate holding unit 2, an imaging unit 3, an illumination unit 4, and an inspection unit 5.

The substrate holding portion 2 mounts the multi-layer substrate W to be inspected, holds it in a specific posture, and moves/rotates or stands still as needed. Specifically, the substrate holding portion 2 includes a substrate holder 20 , an X-axis slider 21 , a Y-axis slider 22 , and a rotating mechanism 23 .

In the substrate holder 20, the outer layer portion of the multilayer substrate W outside the inspection target region R is held from the lower surface or the side surface in a state in which the multilayer substrate W to be inspected is parallel to the XY direction. Specifically, the substrate holder 20 is formed of an annular frame provided with an opening 20h wider than the inspection target region R of the multi-layer substrate W, and is in contact with the outer edge portion of the multi-layer substrate W. Grooves or pores are formed. Moreover, the trough or pore is connected to a vacuum source or a source of compressed air via an on-off valve. Alternatively, the substrate holder 20 may have a mechanism in which a plurality of portions of the outer edge portion of the multi-layer substrate W are sandwiched from the outside toward the inside by a sandwich mechanism or the like, instead of the grooves or the pores.

The X-axis slide 21 is attached to the apparatus frame 1f, and moves the Y-axis slide 22 at an arbitrary speed in the X direction, and is stationary at any position. Specifically, the X-axis slide is composed of a pair of guide rails extending in the X direction, a slider portion that moves on the guide rails, and a slider drive portion that moves/stops the slider portion. The slider drive unit may be constituted by a combination of a servo motor or a pulse motor that is rotated/rested by a signal from an external device, a pulse motor, a ball screw mechanism, or a linear motor mechanism.

The Y-axis slider 22 moves the rotation mechanism 23 at an arbitrary speed in the Y direction, and is arbitrary The position is still. Specifically, the Y-axis slide member is composed of a pair of guide rails extending in the Y direction, a slider portion that moves on the guide rails, and a slider drive portion that moves/stops the slider portion. The slider drive unit may be constituted by a combination of a servo motor or a pulse motor that is rotated/rested by a signal from an external device, a pulse motor, a ball screw mechanism, or a linear motor mechanism.

The rotation mechanism 23 rotates the substrate holder 20 at an arbitrary speed in the θ direction with the Z axis as the center of rotation, and is stationary at an arbitrary angle. Specifically, the rotation mechanism 23 can exemplify a direct drive motor or the like that is rotated/stationary at an arbitrary angle by signal control from an external device. The substrate holder 20 is attached to the member on the rotating side of the rotating mechanism 23 via the connecting member 24.

With this configuration, the substrate holding portion 2 can be placed in the XYθ direction independently or in combination in the XYθ direction as needed in a state in which the substrate W to be inspected is placed and held in a specific posture. Move at a specific speed, angle, and stand at any position and angle.

In the imaging unit 3, the inspection target region R set to the multi-layer substrate W to be inspected is imaged from above.

Specifically, the imaging unit 3 includes a lens barrel 30, a half mirror 31, objective lenses 34a and 34b, and an imaging camera 35.

The lens barrel 30 is a hollow frame body in which the half mirror 31, the objective lenses 34a and 34b, the imaging camera 35, an illumination mechanism to be described later, and the like are fixed at a specific interval, and the unnecessary light from the outside is blocked.

The half mirror 31 reflects the light irradiated from the coaxial epi-illumination 31 described later and irradiates the multi-layer substrate W, and the light reflected from the inspection target region R or the surface from the lower surface of the multi-layer substrate W passes through the inspection target region R. The light (that is, the light 32 emitted from the inspection target region R upward) passes.

The objective lenses 34a and 34b project the image of the multi-layer substrate W on the XY plane and image it on the imaging camera 35. The objective lens 34a, 34b has different projection magnifications, and can be used by the objective lens rotator mechanism Switch properly.

The imaging camera 35 includes, as a light receiving element 36, an area sensor such as a CCD or a CMOS, and the like, and images the light 32 that is emitted upward from the inspection target region R and images corresponding to the image being captured. The signal or data is output to an external machine.

The illumination unit 4 is configured to illuminate the illumination target light to the inspection target region R set on the multi-layer substrate W. Specifically, the irradiation unit 4 includes a reflection illumination unit, a transmission illumination unit 43, and an illumination direction switching unit 46. Here, as one type of the reflection illumination unit of the present invention, a configuration including the coaxial epi-illumination unit 41 will be described as an example.

The coaxial epi-illumination unit 41 is configured to illuminate the illumination light 41L toward the inspection target region R from the optical axis direction of the imaging camera 35 side (that is, above the multi-layer substrate W). The coaxial epi-illumination unit 41 includes a light source unit 41a, a shutter unit 41b, a filter unit 41c, a filter switching unit 41d, and an optical fiber unit 41f.

The light source unit 41a emits light containing visible light and infrared light to the outside. Specifically, the light source unit 41a includes an incandescent lamp such as a halogen lamp, a metal halide lamp, or a xenon lamp, and includes a reflection mechanism called an elliptical lens as needed.

The shutter portion 41b switches between the light emitted from the light source portion 41a toward the outside (that is, the open state) or the blocked (ie, the closed state). Specifically, the shutter portion 41b includes a shielding plate that shields or absorbs light emitted from the light source portion 41a, and an actuator (for example, a solenoid) that rotationally or linearly moves the shielding plate. Further, the shutter unit 41b is in an "open state" in a state shown by a solid line in FIG. 2, and a "off state" in a state shown by a broken line.

The filter portion 41c selectively transmits infrared light or visible light among the light emitted from the light source portion 41a. Specifically, the filter portion 41c includes an infrared light transmission filter that attenuates or reflects the visible light to pass the infrared light, and a visible light transmission filter that attenuates or reflects the infrared light. The visible light passes.

The filter switching unit 41d selectively switches between the infrared light transmitting filter and the visible light transmitting filter using the filter unit 41c to constitute the reflective illumination switching unit of the present invention. specific In other words, the filter switching portion 41d selectively switches the light emitted from the light source portion 41a by rotating or reciprocating the holder with the infrared light transmitting filter and the visible light transmitting filter. The infrared light passes through or passes visible light as the illumination light 41L. This switching operation can be automatically performed by signal control from an external device or manually by an operator.

The optical fiber portion 41f guides the light passing through the filter portion 41c toward the lens barrel 30. Specifically, as the optical fiber portion 41f, a plurality of elongated glass materials, plastic resins, or the like (so-called light guides) may be exemplified.

The illumination unit 43 is configured to illuminate the inspection target region R with the illumination light 43L from the side opposite to the imaging camera 35 (ie, below the multi-layer substrate) via the multi-layer substrate W. The illumination unit 43 includes a light source unit 43a, a shutter unit 43b, a filter unit 43c, a filter switching unit 43d, an optical fiber unit 43f, and a mirror 43e.

The light source unit 43a, the shutter unit 43b, the filter unit 43c, the filter switching unit 43d, and the optical fiber unit 43f can be respectively used with the light source unit 41a, the shutter unit 41b, the filter unit 41c, and the filter switching unit 41d. The optical fiber portion 41f has the same configuration.

The mirror 43e reflects the light guided by the optical fiber portion 43f and illuminates the illumination target light 43L toward the inspection target region R. Specifically, the mirror 43 e is disposed below the opening 20 h of the mounting table 20 so as to face the objective lens 34 a of the imaging unit 3 . Further, the mirror 43e is disposed between the mounting table 20 and the rotating mechanism 23, and does not interfere with the connecting member 24 even when the X-axis slider 21, the Y-axis slider 22, and the rotating mechanism 23 move, and is self-loaded. The opening 20h of the mounting table 20 is disposed to illuminate the illumination light 43L upward.

When the imaging unit 35 of the imaging unit 3 performs imaging, the illumination direction switching unit 46 switches between the illumination light 41L from the upper side generated by the coaxial epi-illumination unit 41 or the lower side generated by the transmission illumination unit 43. Illuminate light 43L, or use both. Specifically, the illumination direction switching unit 46 is connected to the coaxial epi-illumination unit 41 and an actuator (for example, a solenoid) that transmits the shutter portions 41b and 43b of the illumination unit 43, and outputs a control signal. The actuator is ON/OFF. More specifically, the illumination direction switching unit 46 is configured by a control signal output unit such as a personal computer or a sequencer, and can output a specific voltage and current, and apply it to the actuator to switch the shielding plate to open. Status or off state.

According to this configuration, the substrate inspection apparatus 1 can be configured by the filter portion 41c of the coaxial epi-illumination unit 41, the filter switching unit 41d, the filter unit 43c of the transmission illumination unit 43, and the filter switching unit 43d. The illumination direction switching unit 46 switches between the shutter units 41b and 43b, and switches to the mode described below or another mode to perform imaging.

1) Only infrared light (ie infrared reflected light) is illuminated from above

2) Only infrared light is emitted from below (ie infrared transmitted light)

3) Irradiate infrared light (ie, infrared reflected light) from above, and illuminate infrared light from below (ie, infrared transmitted light)

4) Only visible light from above (ie, visible light)

The inspection unit 5 is a checker who specifies the image captured by the imaging camera 35. As the inspection item, the presence or absence of the foreign matter or the bubble, the number of the detected foreign matter or the bubble, the measurement of the size, the confirmation of the pattern shape of the internal structure, the size measurement, and the like can be exemplified.

The inspection unit 5 includes a foreign matter detecting unit 51 and a difference processing unit 52.

The foreign object detecting unit 51 detects a foreign object existing in the inspection target region R based on the image captured by the imaging unit 3 . The difference processing unit 52 is a difference processor that performs a foreign object detection result based on an image captured by the irradiation of the visible light based on the foreign object detection result of the image captured by the infrared light. The inspection unit 5, the foreign object detection unit 51, and the difference processing unit 52 are configured by an image processing device (hardware) and an image processing program (software).

More specifically, the inspection unit 5 may be configured to include a first inspection result recording unit, a second inspection result recording unit, and a third inspection result recording unit. The first inspection result recording unit records the result of the inspection based on the image captured in the first inspection mode. Similarly, the second inspection result recording unit and the third inspection result recording unit are respectively recorded based on the second and third inspection modes. The result of the inspection of the image captured under the formula. Further, the first to third inspection result recording units may be configured by a memory unit constituting the image processing apparatus of the inspection unit 5. Further, the difference processing unit 52 performs a difference process on each inspection result recorded in the first to third inspection result recording units.

The imaging and inspection are performed by switching to the illumination light irradiation mode described below.

1) First inspection mode... Inspection of the multilayer substrate W by infrared light, and in this mode, one of the following is selected.

1-1) Irradiate only infrared light (ie, infrared reflected light) from above

1-2) Only infrared light is emitted from below (ie infrared transmitted light)

1-3) Irradiating infrared light (ie, infrared reflected light) from above, and irradiating infrared light (ie, infrared transmitted light) from below

2) Second inspection mode... inspection of the surface S1 side of the multi-layer substrate W by visible light

3) The third inspection mode... inspection of the back side S2 side of the multilayer substrate W by visible light

[Camera, inspection process]

Fig. 3 is a flow chart showing an example of imaging and inspection of a multi-layer substrate by applying the present invention. First, the multi-layer substrate W is placed on the mounting table 20 so that the surface S1 side is upward (step s101).

Then, the infrared reflected light is irradiated from the surface S1 side of the multi-layer substrate W toward the inspection target region R, and imaging and inspection are performed (step s102). This is referred to as inspection result A.

Then, the visible reflected light is irradiated from the surface S1 side of the multi-layer substrate W toward the inspection target region R, and imaging and inspection are performed (step s103). This is referred to as inspection result B.

Next, the multi-layer substrate W is reversed so that the back surface S2 side is placed upward (step s104).

Next, the visible reflection is irradiated from the S2 side of the back surface of the laminated substrate W toward the inspection target region R. Light is taken, and imaging and inspection are performed (step s105). This is referred to as inspection result C.

Then, the inspection unit 5 performs arithmetic processing on the difference between the inspection result B and the inspection result C based on the inspection result A, and acquires the inspection result D (step s107).

Moreover, the inspection unit 5 outputs the inspection result D as needed (step s108). The form of the output may be exemplified by storing the inspection result D in the memory unit of the image processing apparatus, or displaying the information display on the substrate inspection apparatus, or transmitting data to an external device, or simply sounding an alarm or a buzzer. form.

Fig. 4 is a plan view showing an example of imaging and inspection of a multi-layer substrate inspected by applying the present invention.

4(a), an image in which the inspection target region R of the multi-layer substrate W is imaged in the first illumination light irradiation mode is displayed, and specifically, the surface S1 of the multi-layer substrate W is placed on the upper surface, and An image that is imaged only by infrared light (ie, infrared reflected light) from above. In the first illumination light irradiation mode, in the imaging unit 3, one part of the infrared light is transmitted through the multilayer substrate W, the internal structure, and the cavity portion, and a part of the infrared light is reflected, so that the image is captured as a captured image. image. On the other hand, the foreign matter X1 to X3 existing inside the multi-layer substrate W and the foreign matter Y1 and Y2 adhering to the surface S1 or the back surface S2 of the multi-layer substrate W are scattered by the infrared light on the surface of the foreign matter, so that it is used as a captured image. The camera is a dark image.

4(b), an image in which the inspection target region R of the multi-layer substrate W is imaged in the second illumination light irradiation mode is displayed, and specifically, the surface S1 of the multi-layer substrate W is placed on the upper surface, and An image that is imaged only by illuminating visible light from above. In the second illumination light irradiation mode, since the visible light is reflected on the surface S1 of the multi-layer substrate W in the imaging unit 3, the image is captured as a bright image, and the visible light is attached to the surface of the multi-layer substrate W. The surface of the foreign matter Y1 of S1 is scattered, so that the image is a dark image.

4(c), an image in which the inspection target region R of the multi-layer substrate W is imaged in the third illumination light irradiation mode is displayed, and specifically, the back surface S2 of the multi-layer substrate W is placed on the upper surface, and An image that is imaged only by illuminating visible light from above. In the third illumination light illumination mode In the imaging unit 3, since the visible light is reflected on the back surface S2 of the multi-layer substrate W, the image is captured as a bright image, and the visible light is scattered on the surface of the foreign matter Y2 adhering to the back surface S2 of the multi-layer substrate W. Therefore, the camera is a dark image. Further, since the direction is made to match the above-described Figs. 4(a) and 4(b), the state in which the image is reversed in the X direction or the Y direction is displayed.

4(d), the detected foreign objects X1 to X3, Y1, and Y2 are displayed based on the inspection results of the image captured by the inspection target region R of the multi-layer substrate W in the first illumination light irradiation mode.

4(e), the detected foreign matter Y1 is displayed based on the inspection result of the image captured by the inspection target region R of the multi-layer substrate W in the second illumination light irradiation mode.

In FIG. 4(f), the detected foreign matter Y2 is displayed based on the inspection result of the image captured by the inspection target region R of the multi-layer substrate W in the third illumination light irradiation mode.

In FIG. 4(g), the results of the differential processing by the inspection result difference processing unit (that is, the inspection result) are displayed for the multi-layer substrate W, and only the foreign substances X1 to X3 to be detected are displayed.

With this configuration, the substrate inspection apparatus 1 of the present invention can detect only the foreign matter X1 to X3 existing on the surface of the multi-layer substrate W without detecting the foreign matter Y1 and Y2 adhering to the surface of the multi-layer substrate W.

[Variation 1]

In the above, as the first illumination light irradiation mode, a mode in which only infrared light (i.e., infrared reflected light) from above is irradiated will be described. However, the present invention is not limited to this embodiment, and may be a mode in which only the infrared light from the lower side (that is, the infrared transmitted light) is irradiated as the first illumination light irradiation mode. Specifically, in place of the above-described step s102, the infrared ray transmission light is irradiated from the surface S1 side of the multi-layer substrate W toward the inspection target region R, and imaging and inspection are performed (step s112).

Fig. 5 is a plan view showing another example of the case where the multi-layer substrate inspected by applying the present invention is imaged and inspected. In FIG. 5, an image in which the inspection target region R of the multi-layer substrate W is imaged by infrared transmission light is displayed. In this case, in the imaging unit 3, through the layer The light of the substrate W, the internal structure, and the cavity portion is captured as a bright image, and the foreign matter X1 to X3 existing inside the multi-layer substrate W and the foreign matter Y1 adhering to the surface S1 or the back surface S2 of the multi-layer substrate W , Y2, infrared light absorption or scattering and is captured as a dark image. However, in this case, specific image processing is also performed. As a result of the inspection by the inspection unit 5, the result shown in Fig. 4(d) can be obtained, and the result of the differential processing can also be obtained as shown in Fig. 4(g). Show the results.

[Variation 2]

Further, in addition to the above-described form, the first illumination light irradiation mode may be a form in which the infrared reflected light and the infrared transmitted light are irradiated together. Specifically, in place of the above-described step s102, the infrared reflected light and the infrared transmitted light are irradiated from the surface S1 side of the multi-layer substrate W toward the inspection target region R, and imaging and inspection are performed (step s122).

Fig. 6 is a plan view showing still another example of the case where the multi-layer substrate inspected by applying the present invention is imaged and inspected. In FIG. 6, an image in which the inspection target region R of the multi-layer substrate W is irradiated with both the infrared reflected light and the infrared transmitted light is displayed. In this case, in the imaging unit 3, the infrared light transmitted through the multi-layer substrate W, the internal structure, and the cavity portion is captured as a bright image, and the foreign matter X1 to X3 existing inside the multi-layer substrate W, The infrared light reflected on the upper surface of the foreign matter Y1, Y2 attached to the surface S1 or the back surface S2 of the multi-layer substrate W is imaged as a bright image. On the other hand, since the side portions of the foreign matter X1 to X3, Y1, and Y2 are reflected or scattered by the infrared reflected light, and the infrared transmitted light is absorbed or scattered, the outline portion of the foreign matter is imaged as a dark image in the image pickup unit 3. . However, in this case, specific image processing is also performed. As a result of the inspection by the inspection unit 5, the result shown in Fig. 4(d) can be obtained, and the result of the differential processing can also be obtained as shown in Fig. 4(g). Show the results.

In addition, the form of the first illumination light irradiation mode may be selected as appropriate, and may be appropriately determined depending on the material of the multi-layer substrate to be inspected, the pattern or size of the internal structure, the size of the foreign matter to be detected, and the like.

[Variation 3]

Further, the substrate inspection device 1 described above is configured to select one of three types of illumination patterns for the first illumination light. However, in terms of applying the present invention, it is also possible to adopt a device having any of three types. For example, in the case where only infrared reflected light is used, the illumination unit 4 may not be provided with the transmission illumination unit 42. On the other hand, if only the infrared transmitted light is used, the light source of the illuminating unit 41 of the illuminating unit 4 can be configured to illuminate only the visible light.

[Variation 4]

In the first inspection mode, the surface of the multi-layer substrate W is imaged and inspected toward the imaging unit 4 side, and the inspection result A is obtained, and the inspection results B and C under visible light are performed. The form of the difference and the acquisition and output of the inspection result D will be described.

However, the use of the infrared reflected light and/or the infrared transmitted light allows the infrared light to pass through the surface of the multi-layer substrate W and the internal structure, but the light is attenuated by the surface reflection, so the material of the multi-layer substrate W is used. Or the thickness is different, and it is difficult to detect a foreign matter that has sneaked into the inside of the substrate. In this case, it is preferable to perform imaging and inspection not only on the surface S1 side of the multi-layer substrate W toward the imaging unit 4 side, but also to reverse the multi-layer substrate W so that the multi-layer substrate W has the back surface S2 side. Image pickup and inspection are additionally performed in a state toward the imaging unit 4 side.

Fig. 7 is a flow chart showing another example of imaging and inspection of a multi-layer substrate by applying the present invention. In FIG. 7, steps s101 to s105 (steps s112 and s122 are replaced in place of step s102) described with reference to FIG. 3 are shown to be the same, but thereafter step s106 (or steps s116, s126) shown below, The process of s109, s110.

In this flow, the infrared reflected light is irradiated toward the inspection target region R from the back surface S2 side of the multi-layer substrate W which is placed in the reverse direction, and imaging and inspection are performed (step s106). Alternatively, the infrared transmitted light is irradiated to perform imaging and inspection (step s116). Alternatively, the infrared reflected light and the infrared transmitted light are irradiated to perform imaging and inspection (step s126). Here, these The result obtained in any step is referred to as inspection result A2.

Then, the inspection unit 5 adds the inspection result A2 to the inspection result A, and based on this, calculates the difference between the inspection result B and the inspection result C, and obtains the inspection result D2 (step s109). Moreover, the inspection unit 5 outputs the inspection result D2 as needed (step s110).

[Others, various changes]

Further, in the above, the device configuration and the inspection sequence in the case of manually inverting the multi-layer substrate W are shown. However, in the case where the multi-layer substrate W is to be automatically inverted and the continuity inspection is performed, a configuration including a substrate inversion robot or the like may be employed.

In addition, although the configuration in which one imaging unit 2 is provided on the side of the reflection illumination unit is described above, it may be configured to be provided on the side of the transmission illumination unit 43. Thus, the operation of inverting the substrate when the back surface of the multi-layer substrate W is imaged can be omitted, and the time taken for inspection can be shortened.

In the above, the imaging unit 3 collectively images the inspection target region R. However, the inspection target region R may be divided into a plurality of divided regions, and each of the divided regions may be sequentially imaged. In this case, the substrate inspection apparatus is configured such that the multi-layer substrate W and the imaging camera 35 are relatively moved, and the respective divided regions are imaged by a so-called step-and-repeat method.

Alternatively, the multi-layer substrate W may be continuously moved relative to the imaging camera 35, and the illumination light may be strobed and illuminated, and imaging may be performed at a specific feed pitch. At this time, since the illuminating time of the stroboscopic illumination is extremely short, even if the image is captured during the movement, it is imaged as in the state of the still image.

Further, when the image is acquired by the divided imaging, the inspection and the difference processing may be performed in each of the divided regions, or may be performed on a composite image obtained by combining the captured images into one or a plurality of images.

In addition, as described above, the light source units 41a and 43a for illumination are provided, and the light passing through the filter units 41c and 43c and the filter switching units 41d and 4d is switched. However, the configuration is not limited to this configuration, and a light source that emits a visible light region such as a white LED or a fluorescent lamp or a light source that emits an infrared light region such as an infrared LED may be used as a light source for illumination. In this case, a configuration in which the light is turned ON/OFF can be switched, and a configuration in which the filter portion or the filter switching portion is omitted can be employed.

In addition, when the material of the substrate to be inspected has a property of transmitting infrared light and absorbing visible light, the filter portion 43c and the filter switching portion 43d of the illuminating portion 43 are omitted. The infrared light including the visible light is configured to be irradiated toward the inspection target region R as the illumination light 43L from below. In this case, the foreign matter is imaged as a bright image by the infrared light, and the foreign matter X1 to X3, Y1, and Y2 are captured as a dark image.

In the above, as a form of embodying the present invention, as one type of the reflection illumination unit, the configuration including the coaxial epi-illumination unit 41 is exemplified. However, the reflective illumination unit is not limited to such a form, and may be configured to include the oblique illumination unit 45 indicated by a broken line. The oblique illumination unit 45 can be exemplified by a ring illumination or a dome illumination having a light-emitting unit that is illuminated from one direction as shown by a broken line, or surrounded by an objective lens.

In the above, the inspection form in the case where the foreign matter X1 to X3 sneaked into the inside of the multi-layer substrate W is detected is exemplified. However, the aspect to which the present invention is applied is not limited to this embodiment, and may be applied to whether or not the internal structure of the multi-layer substrate W is formed in a specific size and shape (so-called pattern inspection), or whether the inspection is carried out at the laminate interface. The form of bubbles, etc.

Claims (8)

A substrate inspection apparatus for inspecting an inside of a multi-layer substrate, comprising: an imaging unit that images an inspection target area set on the multi-layer substrate; and a reflection illumination unit that faces the inspection from the imaging unit side The target area is irradiated with infrared light or visible light; and the reflected illumination switching unit switches between the infrared light and the visible light emitted from the reflective illumination unit; and the transmitted illumination unit is directed toward the inspection target area from the side opposite to the imaging unit. Irradiating the infrared light; the illumination direction switching unit switches between the use of the reflective illumination unit and/or the transillumination unit or the use of the illumination unit; the foreign object detection unit detects the presence based on the image captured by the imaging unit a foreign matter in the inspection target area; and a difference processing unit that performs a difference processing of the foreign object detection result based on the image captured by the irradiation of the visible light based on the foreign object detection result of the image captured by the infrared light; The foreign matter detection result of the image captured by the infrared light is reflected by the infrared light irradiated from the reflective illumination unit. The generator; and the result of detecting the foreign matter based on the image captured by the visible light is generated by the visible light irradiated from the reflective illumination unit. A substrate inspection apparatus for inspecting an inside of a multi-layer substrate, comprising: an imaging unit that images an inspection target area set on the multi-layer substrate; and a reflection illumination unit that faces the inspection from the imaging unit side Subject area illumination Infrared light or visible light; a reflected illumination switching unit that switches between the infrared light and the visible light emitted from the reflective illumination unit; and the illumination unit that emits infrared light toward the inspection target area from a side opposite to the imaging unit And an illumination direction switching unit that switches between the reflection illumination unit and/or the transmission illumination unit or the use of the illumination unit; the foreign object detection unit detects the presence of the inspection based on the image captured by the imaging unit a foreign matter in the target area; and a difference processing unit that performs a difference process of the foreign object detection result based on the image captured by the irradiation of the visible light based on the foreign object detection result of the image captured by the infrared light; and based on the irradiation The foreign matter detection result of the image captured by the infrared light is generated by the infrared light irradiated from the reflective illumination unit and the infrared light irradiated from the transparent illumination unit; and the image captured based on the visible light is irradiated The result of the foreign matter detection is generated by the visible light irradiated from the reflective illumination unit. A substrate inspection method for inspecting an inside of a multi-layer substrate, comprising: an imaging step by infrared reflected light, which irradiates infrared light to an inspection target region set on the multi-layer substrate, and the inspection is performed from the inspection The first main surface imaging step is performed by the visible light, and the visible light is emitted from the first main surface side of the multi-layer substrate toward the inspection target region, and the inspection target region is emitted from the inspection target region. Reflecting light imaging; a step of inverting the front and back surfaces of the multi-layer substrate; and a second main surface imaging step by visible reflected light from the above-mentioned multi-layer base The second main surface side of the plate irradiates the inspection target area with visible light, and images the light reflected from the inspection target area; and the inspection result based on the image obtained by the imaging step by the infrared reflected light, Differentially processing the inspection result based on the image obtained by the first main surface imaging step by visible reflected light and the inspection result based on the image obtained by the second main surface imaging step by visible reflected light step. The substrate inspection method according to claim 3, wherein the imaging step by the infrared reflected light includes the step of irradiating infrared light from the first main surface side of the multi-layer substrate toward the inspection target region from the inspection target region The reflected light is imaged from the first main surface side of the multi-layer substrate; the front and back surfaces of the multi-layer substrate are reversed; and infrared light is emitted from the second main surface side of the multi-layer substrate toward the inspection target region. The light reflected by the inspection target region is imaged from the second main surface side of the multilayer substrate. A substrate inspection method for inspecting an inside of a multi-layer substrate, comprising: an imaging step by infrared transmission light, which irradiates infrared light to an inspection target region set on the multi-layer substrate, and passes the inspection Light imaging of the target region; the first main surface imaging step by visible reflected light, which is to illuminate the inspection target region from the first main surface side of the multi-layer substrate, and reflects the inspection target region Light imaging; a step of inverting the front and back surfaces of the multi-layer substrate; and a second main surface imaging step by visible reflected light, which is illuminated from the second main surface side of the multi-layer substrate toward the inspection target area Light, and the light reflected from the inspection target area is photographed; and An inspection result based on an image obtained by the first main surface imaging step by visible reflected light and based on a visible reflection based on an inspection result of an image obtained by an imaging process by the infrared transmitted light The step of performing the difference processing on the inspection result of the image obtained by the second main surface imaging step of the light. The substrate inspection method according to claim 5, wherein the imaging step by the infrared transmitted light includes the step of irradiating infrared light from the first main surface side of the multi-layer substrate toward the inspection target region, and passing the inspection target region Light is imaged from the second main surface side of the multi-layer substrate; the front and back surfaces of the multi-layer substrate are reversed; and infrared light is emitted from the second main surface side of the multi-layer substrate toward the inspection target region, and the inspection is passed. The light of the target region is imaged from the first main surface side of the multilayer substrate. A substrate inspection method for inspecting an inside of a multi-layer substrate, comprising: an imaging step by infrared reflected light and infrared transmitted light, which irradiates infrared light to an inspection target region set on the multi-layer substrate, The light reflected from the inspection target region and the light imaging through the inspection target region; and the first main surface imaging step by visible reflected light from the first main surface side of the multi-layer substrate toward the inspection target region Irradiating visible light, imaging light reflected from the inspection target region; step of inverting the front and back surfaces of the multi-layer substrate; and scanning a second main surface by visible reflected light from the multi-layer substrate (2) the main surface side illuminates the visible light toward the inspection target area, and images the light reflected from the inspection target area; and the inspection result based on the image obtained by the imaging process by the infrared transmitted light and the infrared reflected light, For the first master based on visible reflected light The inspection result of the image obtained by the surface imaging step and the step of performing the difference processing based on the inspection result of the image obtained by the second main surface imaging step by the visible reflected light. The substrate inspection method according to claim 7, wherein the imaging step by the infrared transmitted light and the infrared reflected light includes the step of irradiating infrared light from the first main surface side of the multi-layer substrate toward the inspection target region. The light reflected by the inspection target region is imaged from the first main surface side of the multi-layer substrate, and the light passing through the inspection target region is imaged from the second main surface side of the multi-layer substrate; And irradiating infrared light to the inspection target region from the second main surface side of the multi-layer substrate, and capturing light reflected from the inspection target region from the second main surface side of the multi-layer substrate, and passing the inspection The light in the target region is imaged from the second main surface side of the multilayer substrate.