TW202220078A - Appearance inspection device and method - Google Patents

Abstract

Provided are an appearance inspection device and method that make it possible to obtain a desired inspection result without detecting a pseudo defect even if a location under inspection includes a variable region where outer edge position deviation or dimension error is permitted. Specifically, this appearance inspection device for inspecting the appearance of a location under inspection comprises an inspection image acquisition unit for acquiring an inspection image, an inspection reference image registration unit for registering a reference image to serve as a reference for inspection, and an inspection unit for carrying out inspection by comparing the inspection image and reference image. The location under inspection includes a variable region where outer edge position deviation or dimension error is permitted. There is an edge detection unit for detecting the position of the outer edge of the variable region. A variable region reference image serving as a reference for inspecting the variable region is registered as a reference image. The inspection unit inspects the variable region in the inspection image by comparing the variable region and a region in the variable region reference image that has a position corresponding to that of the variable region on the basis of the position of the outer edge detected by the edge detection unit.

Description

Appearance inspection device and method

The present invention relates to a visual inspection apparatus and method for inspecting an inspection object part by comparing an inspection image photographed with a reference image of the inspection object part. For example, a wafer appearance inspection apparatus and method for photographing the appearance of a semiconductor element etc. formed on a wafer, and performing the quality judgment of the semiconductor element etc. are performed.

After a semiconductor element is layered on a semiconductor wafer to form multiple semiconductor element circuits (ie, the repeating appearance pattern of the element wafer), it is singulated into individual chip parts, and the chip parts are packaged and shipped as electronic parts. Or incorporated into electrical products.

Further, before each chip component is singulated, an inspection image and a reference image of the repeating appearance pattern of the element chip formed on the wafer are photographed, and inspections regarding the quality of each chip component are performed (eg, Patent Document 1).

In addition, there is known a technique for reducing erroneous detection due to alignment errors by aligning the inspection target image and the reference image and then performing defect detection (for example, Patent Document 2).

On the other hand, it is known to perform subtraction processing (ie, comparison) between the inspection image and the reference image, and mask and eliminate the noise generated due to the deviation of pattern matching at the boundary portion of the image (for example, patent Reference 3). [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2007-155610 [Patent Document 2] Japanese Patent Laid-Open No. 2003-4427 [Patent Document 3] Japanese Patent Laid-Open No. 2000-335062

[Problems to be Solved by Invention]

The inspection object, that is, a semiconductor element, includes a plurality of adjacent regions with different properties. For example, when a chip component is to be inspected, a wiring circuit pattern or external connection terminals (so-called electrode pads and ground portions) are formed on the surface of the wafer.

Since the wiring circuit pattern is deeply related to the performance of the device chip, strict inspection is required for disconnection or short circuit, difference in line width, and foreign matter.

On the other hand, since the external connection terminal only needs to be capable of bonding or conducting with external elements, lead wires, etc., the positional deviation and dimensional error of the outer edge are not strictly required as in the wiring circuit pattern.

Therefore, when an area (variation area) that allows for positional deviation or dimensional error of the outer edge is included in the inspection image of the inspection object portion, the position of the boundary (ie, the outer edge) of the surrounding area (peripheral area) is included. Varies in each inspection image. In this way, when compared with the reference image, the position of the outer edge in the inspection image that varies in position is detected as a defect (so-called suspected defect), which is a major cause of a decrease in the yield of the device wafer.

In addition, the prior art such as Patent Documents 2 and 3 presupposes that the size, range, pattern, etc. of the reference image are specified, and cannot cope with changes in the size of the inspection target portion.

Therefore, the present invention has been made in view of the above-mentioned problems; The object is to provide a visual inspection apparatus and method that can obtain desired inspection results without detecting suspected defects even if the inspection object includes a variation region that allows positional deviation or dimensional error of the outer edge. [Technical means to solve problems]

In order to solve the above problems, one aspect of the present invention is an appearance inspection device, which is a device for photographing the appearance of an inspection object part and inspecting it; and has: An inspection image acquisition unit that acquires an appearance image of the inspection object portion as an inspection image; An inspection reference image registration unit that registers a reference image that becomes a reference for inspection of the inspection target portion; and An inspection unit that compares the inspection image with the reference image and inspects the inspection target portion; and The inspection object part includes the allowable outer edge position deviation or dimensional error variation area; and has: an edge detection section that processes the inspection image and detects the position of the outer edge of the variable area; and As the reference image, a reference image of the variation area that is set as the inspection standard for the variation area and whose outer edge is set wider than the standard range is registered; The inspection unit compares the variation area of the inspection image with an area corresponding to the position of the variation area in the variation area reference image based on the position of the outer edge detected by the edge detection unit, and checks the variation area.

Also, another aspect of the present invention is an appearance inspection method, which is a method for inspecting an inspection target portion by comparing an inspection image and a reference image of the appearance of a portion to be inspected, and comprising: a reference image registration step, which pre-registers a reference image; An examination image acquisition step, which acquires an examination image; and An inspection step of comparing the inspection image and the reference image and inspecting the inspection object portion; and The inspection object part includes the allowable outer edge position deviation or dimensional error variation area; and has: The step of registering, as a reference image, a reference image of a variation area that is set to a range wider than the standard range to be the inspection standard for the variation area; and an edge detection step that processes the inspection image to detect the location of the outer edge of the changed region; and In the inspection step, the changed area of the inspection image is compared with an area corresponding to the position of the changed area in the changed area reference image based on the position of the outer edge detected in the edge detection step, and the changed area is inspected. [Effect of invention]

Even in the inspection object part, including the position deviation of the outer edge or the variation area of the dimensional error, the expected inspection result can be obtained without detecting the suspected defect.

Below, the form for implementing this invention is demonstrated using drawings. In the following description, the three axes of the orthogonal coordinate system are represented by X, Y, and Z, the horizontal direction is represented by the X direction and the Y direction, and the direction perpendicular to the XY plane (that is, the direction of gravity) is represented by Z. direction. In addition, the Z direction expresses the direction opposite to gravity as upward, and the direction in which gravity acts as downward. In addition, let the direction of rotation about the Z direction as the central axis be the θ direction.

FIG. 1 is an image diagram showing an example of an inspection image as an example of an embodiment of the present invention. FIG. 1 shows an example of the inspection image Px in which the inspection object region Rx is captured. In addition, the inspection object portion Rx includes a variation region Rx1 that allows positional deviation or dimensional error of the outer edge B, and a peripheral region Rx2 adjacent to the variation region Rx1.

In addition, in the following description, it is shown that in the element wafer C formed on the wafer W, the external connection terminal formed by the plating step is set as the variation region Rx1 in the inspection object portion Rx, and the wiring circuit pattern and the like are set as the inspection An example of the peripheral region Rx2 in the target part Rx.

FIG. 2 is a schematic diagram showing the overall configuration of an example of an embodiment of the present invention. FIG. 2 schematically shows each part constituting the wafer appearance inspection apparatus 1 according to the present invention.

The wafer appearance inspection apparatus 1 captures and inspects the appearance of the inspection object portion Rx set on the surface of the wafer W. As shown in FIG. For example, the inspection image Px is obtained while the repeating appearance pattern of the element wafer C (a type of semiconductor element) formed on the wafer W at specific intervals in the XY direction is successively photographed, and the inspection image Px is obtained and compared with the pre-registered reference image Pf , whereby the entire surface of the wafer W is continuously inspected. Specifically, the wafer appearance inspection apparatus 1 includes an inspection image acquisition unit 2 , an inspection reference image registration unit 3 , an edge detection unit 4 , an inspection unit 5 , and the like.

More specifically, the wafer appearance inspection apparatus 1 includes a wafer holding unit H, an imaging unit S, a relative moving unit M, a computer CP, a controller CN, and the like.

The examination image acquisition unit 2 acquires the external appearance image of the examination object region Rx as the examination image Px. Specifically, the inspection image acquisition unit 2 is constituted by the imaging unit S and the input unit of the computer CP.

FIG. 3 is a conceptual diagram showing a state in which an external image in an example of an embodiment of the present invention is captured. 3 shows a situation in which the imaging camera S5 having the imaging unit S relatively moves in the direction indicated by the arrow Vs with respect to the wafer W, while successively photographing the appearance of the device chips C formed on the wafer W at specific intervals along the XY direction.

Specifically, during the relative movement of the relative moving part M (for example, moving in the direction of the arrow Vs), the lighting part S1 is strobe light at predetermined intervals or positions, and the camera S5 captures the same appearance as a still image. picture. And the external appearance image output from the imaging camera S5 is input as the inspection image Px to the input part of the computer CP (that is, the inspection image Px is acquired).

The inspection reference image registration unit 3 registers a reference image Pf serving as an inspection reference for the inspection target region Rx. Specifically, the inspection reference image registration unit 3 registers the fluctuation region reference image Pf1 or the peripheral region reference image Pf2 as the reference image Pf.

More specifically, the examination reference image registration unit 3 is constituted by a memory unit or an auxiliary memory unit of the computer CP.

FIG. 4 is an image diagram showing an example of a reference image in an example of an embodiment of the present invention. FIG. 4( a ) shows an example of the variation area reference image Pf1 which is one of the reference images Pf. FIG. 4(b) shows an example of the peripheral area reference image Pf2, which is one of the reference images Pf.

The variation area reference image Pf1 serves as a reference for the variation area Rx1, and the outer edge B1 of the variation area Rx1 is set to be wider than the standard range Rs. The range of the outer edge B1 of the variable region Rx1 is wider than that of the standard range Rs, which does not mean that the area is wider, but that the entire circumference of the outer edge B1 is located further outside than the standard range Rs. On the other hand, the peripheral area reference image Pf2 serves as a reference for the inspection of the peripheral area Rx2, and the outer edge B2 of the variation area Rx1 is set to a range narrower than the standard range Rs. The range of the outer edge B2 of the variable region Rx1 is narrower than the standard range Rs is not because the area is narrow, but the entire circumference of the outer edge B1 is located more inward than the standard range Rs.

In addition, the variation area reference image Pf1 or the peripheral area reference image Pf2 is prepared and selected in advance to allow the variation of the outer edge B of the variation area Rx1 as a limit sample, and registered in the inspection reference image registration unit 3 in advance.

The edge detection unit 4 processes the inspection image Px and detects the position of the outer edge B of the variable region Rx1 (ie, the boundary with the peripheral region Rx2 ). Specifically, the edge detection unit 4 performs difference processing, differentiation processing, etc. on each pixel included in the inspection image Px, and outputs position information of the pixel determined to be the outer edge B of the variation region Rx1. More specifically, the edge detection unit 4 is constituted by a processing unit or an image processing unit of the computer CP and an execution program.

The inspection unit 5 compares the inspection image Px and the reference image Pf, and inspects the inspection object region Rx, that is, compares the variation area Rx1 of the inspection image Px with the variation area based on the boundary position detected by the edge detection unit 4 The area corresponding to the position of the variation area Rx1 in the reference image Pf1 is checked for the variation area Rx1.

Furthermore, the inspection unit 5 compares the peripheral area Rx2 of the inspection image Px with the area corresponding to the peripheral area Rx2 position in the peripheral area reference image Pf2 based on the boundary position detected by the edge detection unit 4, and inspects the peripheral area Rx2. By. Specifically, the inspection unit 5 compares the luminance values of the pixels in the reference image Pf1 corresponding to the position of the change area Rx1 with respect to each pixel of the change area Rx1 of the inspection image Px, and determines whether the difference in luminance is within a specific range ( That is, within the acceptance criteria). More specifically, the inspection unit 5 is composed of a processing unit or an image processing unit of the computer CP and an execution program.

The wafer holding part H holds the wafer W. Specifically, the wafer holding portion H holds the wafer W from the lower surface side and supports the wafer W in a horizontal state. More specifically, the wafer holding portion H includes a mounting table H1 whose upper surface is horizontal. The mounting table H1 is provided with a groove portion or a hole portion in a portion in contact with the wafer W, and the groove portion or the hole portion is connected to a negative pressure generating mechanism such as a vacuum pump through a switching valve or the like. In addition, the wafer holding portion H can hold or release the holding of the wafer W by switching the groove portions or the hole portions to a negative pressure state or a ventilated state.

The imaging unit S captures the appearance of the inspection target portion and outputs image data. Specifically, the imaging unit S includes a lens barrel S0, an illumination unit S1, a half mirror S2, a plurality of objective lenses S3a and S3b, an objective lens rotator mechanism S4, an imaging camera S5, and the like.

The lens barrel S0 fixes the illumination part S1, the half mirror S2, the objective lenses S3a, S3b, the objective lens rotator mechanism S4, the imaging camera S5, etc. in a specific posture, and guides the illumination light L1 or the observation light L2. The lens barrel S0 is attached to the apparatus frame 1f via a connecting metal fitting or the like (not shown).

The illumination part S1 emits illumination light L1 required for imaging. Specifically, a laser diode, a metal halide lamp, a xenon lamp, LED (Light Emitting Diode: Light Emitting Diode) illumination etc. can be illustrated as the illumination part S1. More specifically, the lighting unit S1 is controlled based on a signal from the outside to switch light-on/off, or to strobe light at a specific place or timing.

The half mirror S2 reflects the illumination light L1 emitted from the illumination unit S1 and irradiates it to the wafer W side, and allows the incident light (also referred to as reflected light and scattered light. That is, observation light) L2 from the wafer W side to pass through to the side of the wafer W. Video camera S5 side.

The objective lenses S3a and S3b are used for imaging the image of the imaging area on the workpiece W on the imaging element of the imaging camera S5 at specific observation magnifications different from each other.

The objective lens rotator mechanism S4 uses or switches either of the objective lenses S3a and S3b. Specifically, the objective lens rotator mechanism S4 is controlled by manual operation or external signals, and rotates and stops at each specific angle.

The imaging camera S5 images the imaging area F on the workpiece W, and acquires the inspection image Px or the reference image Pf. The acquired images are output to the outside (in this embodiment, the computer CP) as image signals or image data.

The relative moving unit M is one that relatively moves the wafer holding unit H and the imaging unit S. Specifically, the relative moving part M includes an X-axis slider M1, a Y-axis slider M2, and a rotation mechanism M2.

The X-axis slider M1 is installed on the device frame 1f, so that the Y-axis slider M2 moves at an arbitrary speed along the X direction, and is stationary at an arbitrary position. Specifically, the X-axis slider is composed of a pair of rails extending in the X direction, a slider portion that moves on the rails, and a slider drive portion that moves and stops the slider portion.

The Y-axis slider M2 is based on the control signal output from the control unit CN, so that the rotating mechanism M3 moves at an arbitrary speed along the Y direction, and is stationary at an arbitrary position. Specifically, the Y-axis slider is composed of a pair of rails extending in the Y direction, a slider portion that moves on the rails, and a slider drive portion that moves and stops the slider portion.

The slider driving parts of the X-axis slider M1 and the Y-axis slider M2 can be a combination of a servo motor or a pulse motor and a ball screw mechanism that is controlled by a signal from the control part CN to rotate and stop, or a linear motor mechanism, etc. constitute.

The rotation mechanism M3 rotates the mounting table H1 at an arbitrary speed in the θ direction, and is stationary at an arbitrary angle. Specifically, the rotation mechanism M3 can be exemplified by being controlled by a signal from an external device such as a direct drive motor to rotate/rest at an arbitrary angle. The mounting table H1 of the wafer holding|maintenance part H is attached to the member of the rotation side of the rotation mechanism M3.

Since the relative moving part M is configured in this way, the wafer W can be opposed to the imaging part S in the XYθ direction independently or in combination at a specific speed or angle while holding the wafer W to be inspected. Move, or stand still at any position or angle.

The computer CP is the one that inputs signals or data from the outside, performs specific arithmetic processing or image processing, and outputs signals or data to the outside, and performs functions such as the following. ・Registration, switching, etc. of inspection image registration mode and inspection mode (ie, operation mode) ・Check the registration, switching, etc. of the camera magnification of the image registration mode ・Acquisition, registration, etc. of the reference image Pf in the inspection image registration mode ・Registration of inspection recipes in inspection mode (scanning position or order, imaging interval (pitch, interval), moving speed, etc.), switching of inspection recipes to be used, etc. ・Image processing of inspection image Px or reference image Pf ・Position detection (edge detection) of the outer edge B of the change region Rx in the inspection image Px of the inspection mode, acquisition of position information of the outer edge B, etc. ・Comparison of the inspection image Px in the inspection mode with the reference image Pf (ie, inspection) More specifically, the computer CP consists of an input part and an output part, a memory part (called a register or a memory), a control part and an arithmetic part (called a CPU (Central Processing Unit) or an MPU (Micro Processor) Unit: Microprocessing Unit)), image processing device (called GPU (Graphics Processing Unit: Graphics Processing Unit)), auxiliary memory device (HDD (Hard Disk Drive: hard disk drive) or SSD (Solid State Disk: solid state) Disk), etc.) (ie, hardware), and its executable program, etc. (ie, software).

The controller CN is a device that inputs and outputs signals or data with external devices (each device of the imaging unit S or the relative moving unit M, a computer CP, etc.), performs specific control processing, and performs functions such as the following. ・Outputs a signal for holding/releasing the wafer W to the wafer holding unit H ・Controlling the objective lens rotator mechanism S4 to switch the objective lens to be used (imaging magnification) ・Output a strobe light signal to the lighting unit S1 ・Output camera trigger to camera S5 ・Input image output from camera S5 (check image or reference image) ・Drive control of the relative moving part M: The function of monitoring the current positions of the X-axis slider M1, Y-axis slider M2, and rotating mechanism M3, and outputting and controlling the driving signal That is, the controller CN can drive and control the relative moving part M, and can output an imaging trigger to the imaging part S while changing the location of the imaging area F set on the wafer W. Furthermore, a desired image can be obtained by outputting an imaging trigger while switching the imaging magnification or field of view size and changing the imaging interval according to the type of inspection.

In addition, the output of the imaging trigger can be exemplified in the following manner. ・While scanning and moving in the X direction, the illumination light L1 emits light for a very short time (so-called stroboscopic light) every time it moves a certain distance. ・A method of moving and stationary at a specific position, irradiating illumination light L1 and photographing (so-called step & repeat).

More specifically, the controller CN is constituted by a part of the computer CP or a dedicated programmable logic controller, etc. (ie, hardware), and an execution program thereof (ie, software).

<Operation Mode and Operation Flow> The wafer appearance inspection apparatus 1 has an inspection image registration mode and an inspection mode, and can be switched and operated.

FIG. 5 is a flow chart showing an example of an embodiment of the present invention. FIG. 5( a ) shows a series of flows of images (ie, reference images) captured by the wafer appearance inspection apparatus 1 and registered as an inspection reference of the device wafer C placed on the wafer W (ie, reference images) for each operation step. This is called the inspection image registration flow, and the mode that operates by the following operation flow is the inspection image registration mode.

First, the wafer W for registering the reference image Pf is mounted on the mounting table H1 of the wafer appearance inspection apparatus 1 (step s1 ). In this wafer W, the element wafer C which becomes the reference|standard of a good-or-nothing judgment is included.

Next, the alignment marks and the like formed on the wafer W are read, and the alignment of the wafer W is performed (step s2 ).

Next, the relative moving unit M is controlled to move the wafer W to a position (ie, an imaging position) where the imaging unit S can capture the element wafer C set as the reference image Pf (ie, imaging position) (step s3 ).

Next, the reference image Pf is captured by the imaging unit S, and the reference image Pf is registered in the inspection reference image registration unit 3 (step s4). Specifically, the reference image Pf for inspecting the variation area Rx1 is registered as the variation area reference image Pf1.

Further, it is determined whether or not to capture and register a reference image (step s5 ), and in the case of capture and registration, the above steps s3 to s5 are repeated. Specifically, the reference image Pf for inspecting the surrounding area Rx2 is registered as the surrounding area reference image Pf2. On the other hand, if it is not necessary to further capture and register the reference image, the wafer W is released (step s6 ).

In addition, it is judged whether or not to capture and register a reference image even on another wafer (step s7 ), and the above-mentioned steps s1 to s7 are repeated in the case of capture and registration. On the other hand, if it is not necessary to capture and register the reference image, the series of flows ends.

FIG. 5( b ) shows a series of flow in which the appearance image Px of the element chip C arranged on the wafer W is captured by the wafer appearance inspection apparatus 1 and the inspection is performed based on the image in each operation step. This is called an inspection flow, and a mode operated by the following operation flow is an inspection mode.

First, an inspection recipe is newly registered or selected from a pre-registered inspection recipe, and the wafer W is placed on the mounting table H1 (step s11 ).

Next, the alignment marks etc. formed on the wafer W are read, and the alignment of the wafer W is performed (step s12).

Next, the element wafer C is imaged by the imaging unit S while the relative moving unit M is controlled to move the wafer W, and an inspection image Px is acquired (step s13 ).

Next, the edge detection unit 4 detects the position of the outer edge B of the variation region Rx1 in the acquired inspection image Px (step s14).

Next, the inspection is performed by comparing the variation area Rx1 in the inspection image Px with the area corresponding to the position of the variation area Rx1 in the pre-registered variation area reference image Pf1 (step s15 ). Specifically, the inspection unit 5 compares the variation area Rx1 in the inspection image Px with the position of the outer edge B of the variation area Rx1 detected by the edge detection unit 4 in the inspection image Px with the variation area reference image. The area corresponding to the position of the variation area Rx1 in Pf1 is checked for the variation area Rx1.

Furthermore, the inspection is performed by comparing the peripheral region Rx2 of the inspection image Px with the region corresponding to the position of the peripheral region Rx2 of the peripheral region reference image Pf2 registered in advance. Specifically, the inspection unit 5 compares the peripheral area Rx2 of the inspection image Px with the position of the outer edge B of the variation area Rx1 detected by the edge detection unit 4 of the inspection image Px and the peripheral area reference image Pf2 The area corresponding to the position of the surrounding area Rx2 is checked to check the surrounding area Rx2.

Next, another inspection image Px is acquired to determine whether to continue the inspection or the like (step s16 ), and in the case of continuing the inspection or the like, the above-mentioned steps s13 to s16 are repeated. On the other hand, if further inspection and the like are not required, the wafer W is released (step s17 ).

In addition, it is determined whether or not an inspection image is acquired and inspected for other wafers (step s18 ), and the above-mentioned steps s11 to s18 are repeated in the case of further inspection or the like. On the other hand, if no further inspection or the like is required, the series of flows ends.

Since the wafer appearance inspection apparatus 1 of the present invention has such a configuration, Even if the inspection target portion Rx includes a variation region Rx1 that allows positional deviation or dimensional error of the outer edge, a desired inspection result can be obtained without detecting a suspected defect. [Other forms, variations] In addition, in the above-mentioned example, in addition to the variation area Rx1 of the inspection image Px, the inspection unit 5 compares the peripheral area Rx2 with the peripheral area in the peripheral area reference image Pf2 based on the position of the outer edge B detected by the edge detection unit 4 The composition of the area corresponding to the location of area Rx2 is checked. However, in terms of embodying the present invention, the inspection of the peripheral region Rx2 may not be performed, and only the inspection of the variable region Rx1 may be performed.

In the above description, the inspection target portion Rx is shown as a semiconductor element or the like formed on the wafer W, and an example of an external connection terminal formed on the wafer W by the plating step is set as the variation region Rx1 of the inspection target portion Rx. In the plating step, since the amount of the deposited plating material is not specific, the line width or positional accuracy of the wiring circuit pattern varies depending on the amount of the deposited material. In addition, the external connection terminals formed by the plating step do not strictly define the line width or the positional accuracy as much as the wiring circuit pattern inside the element, but allow positional deviation or dimensional accuracy. Therefore, if such a part is set as an inspection object, a desired inspection result can be obtained without detecting a suspected defect. However, the present invention can also be applied to the inspection of other inspection object parts in addition to the external connection terminal formed by the plating step.

In the above, although the configuration in which the inspection object portion Rx is set on the surface of the wafer W is exemplified, it may be set on the intermediate layer (eg, the bonding surface, etc.) of the laminated substrate. In this case, the imaging unit S may be configured to appropriately select a wavelength that transmits through other laminated films or wafers as the illumination light L1 to irradiate the inspection target site, and the imaging camera S5 acquires the observation light L2.

In the above, the wafer appearance inspection apparatus 1 is shown as an example, and the imaging position of the device wafer C to be inspected on the wafer W in the XY directions is changed, and the inspection image Px is captured (that is, acquired). However, after the present invention is embodied, the relative movement unit M, the imaging unit S, etc. are not necessarily configured, and may be configured to be received by the input unit of the computer CP (that is, acquired by the inspection image acquisition unit 2) and stored in memory. In the inspection image Px sent from the host computer or external device having the inspection image Px, the position of the outer edge of the variation region Rx1 included in the inspection image Px is detected by the edge detection unit 4 in the same manner as described above, and the inspection unit 5 performs the detection. The same inspection as above (so-called offline inspection).

1: Wafer appearance inspection device 1f: Device frame 2: Check the image acquisition section 3: Check the reference image registration section 4: Edge detection section 5: Inspection Department B: Outer edge (boundary) B1: Outer edge B2: Outer edge C: Component wafer (wafer parts) EN:controller CP: computer F: Camera area (field of view) H: Wafer Holder H1: Mounting table L1: Illumination light L2: Light incident from the wafer side (reflected light, scattered light) M: Relative moving part M1: X-axis slider M2: Y-axis slider M3: Rotary Mechanism Pf: benchmark image Pf1: Changed area reference image Pf2: Peripheral area reference image Px: check image Rs: Standard range RP: Recipe Registration Department Rx: Inspection object part Rx1: Change area (inspection target part) Rx2: Surrounding area (inspection target area) S: camera department S0: lens barrel S2: Half mirror S3a: Objective lens S3b: Objective lens S4: Objective rotator mechanism S5: Camcorder s1～s7: steps s11～s18: Steps Vs: Arrow W: Wafer

FIG. 1 is an image diagram showing an example of an inspection image in an example of an embodiment of the present invention. FIG. 2 is a schematic diagram showing the overall configuration of an example of an embodiment of the present invention. FIG. 3 is a conceptual diagram showing a state in which an external image is captured in an example of a form embodying the present invention. 4(a) and (b) are image diagrams showing an example of a reference image in an example of an embodiment of the present invention. Fig.5 (a), (b) is a flowchart in an example of the form which embodies this invention.

1: Wafer appearance inspection device

1f: Device frame

2: Check the image acquisition section

3: Check the reference image registration section

4: Edge detection section

5: Inspection Department

C: Component wafer (wafer parts)

EN:controller

CP: computer

F: Camera area (field of view)

H: Wafer Holder

H1: Mounting table

L1: Illumination light

L2: Light incident from the wafer side (reflected light, scattered light)

M: Relative moving part

M1: X-axis slider

M2: Y-axis slider

M3: Rotary Mechanism

Pf1: Changed area reference image

Pf2: Peripheral area reference image

Px: check image

S: camera department

S0: lens barrel

S2: Half mirror

S3a: Objective lens

S3b: Objective lens

S4: Objective rotator mechanism

S5: Camcorder

W: Wafer

Claims (5)

An appearance inspection device is characterized in that it is a device for photographing and inspecting the appearance of an inspection object part, and has: An inspection image acquisition unit that acquires an appearance image of the inspection object portion as an inspection image; An inspection reference image registration unit that registers a reference image as an inspection reference for the above-mentioned inspection target portion; and An inspection unit that compares the inspection image and the reference image to inspect the inspection target portion; and The above-mentioned inspection object part includes a variation area that allows the positional deviation or dimensional error of the outer edge; and has: an edge detection unit that processes the inspection image to detect the position of the outer edge of the variable region; and As the above-mentioned reference image, the above-mentioned outer edge of the above-mentioned fluctuating area is registered and set to be a wider range than the standard range, and becomes the inspection standard of the fluctuating area. Reference image; The inspection unit compares the variation area of the inspection image with an area corresponding to the position of the variation area in the variation area reference image based on the position of the outer edge detected by the edge detection unit, and checks the variation area . The visual inspection device of claim 1, wherein As the reference image, a peripheral area reference image in which the variation area is set to a range narrower than the standard range is registered as an inspection reference for the peripheral area further outside the outer edge of the variation area; The inspection unit compares the peripheral area of the inspection image with an area corresponding to the location of the peripheral area in the peripheral area reference image based on the position of the outer edge of the fluctuation area detected by the edge detection unit, to check the surrounding area. The visual inspection device of claim 1 or 2, wherein The above-mentioned inspection object portion is a semiconductor element formed on a wafer, etc.; The external connection terminals formed on the wafer by the plating step are set as the fluctuation region in the inspection object portion. An appearance inspection method, characterized in that it is a method for inspecting the inspection object portion by comparing an inspection image and a reference image of the appearance of the inspection object portion, and has: a reference image registration step, which pre-registers the above-mentioned reference image; An inspection image obtaining step, which obtains the above-mentioned inspection image; and An inspection step of inspecting the inspection object portion by comparing the inspection image and the reference image; and The above-mentioned inspection object part includes a variation area that allows the positional deviation or dimensional error of the outer edge; and has: The step of registering, as the reference image, a reference image of the variation area that is set as the inspection standard for the variation area with the variation area set to a wider range than the standard range; and an edge detection step, which processes the inspection image to detect the position of the outer edge of the change region; and In the inspection step, the change region of the inspection image is compared with the region corresponding to the position of the change region in the change region reference image based on the position of the outer edge detected in the edge detection step, and the inspection is performed. the change area. As in the visual inspection method of claim 4, it has the following steps: As the reference image, a surrounding area reference image that is set to be a range narrower than the standard range is registered as a reference for the inspection of the surrounding area; and In the inspection step, the peripheral area of the inspection image is compared with an area corresponding to the peripheral area position in the other area reference image based on the boundary position detected in the edge detection step, to inspect the peripheral area area.

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