JP3455031B2 - Bump appearance inspection device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting the appearance of bumps, which are minute projections formed on the electrode portion of a semiconductor chip (hereinafter simply referred to as a chip).

[0002]

2. Description of the Related Art Conventionally, as a device of this type, FIGS.
There is one shown in. This device is disclosed in Japanese Patent Laid-Open No. 04-1132.
No. 59, the chip 102 on which the bump 101 is formed is placed on the base 103, and the chip 102
Are radiated by two types of illumination methods, a dark illumination method and a bright field illumination method, and the chip surface 102a is imaged by the CCD camera 105. C under the dark field illumination method and the bright field illumination method respectively.
The output signal of the CD camera 105, that is, the image signal is subjected to image processing by the computer image processing device 106, the characteristic value of the bump 101 is extracted from the image data obtained by this, and the extracted characteristic value of the bump is stored in advance. By comparing it with the characteristic value of the good bump, the goodness and the badness of the bump are determined.

The dark field illumination method is the CCD camera 10.
5 is an illumination method of irradiating the chip surface 102a with an acute irradiation angle by light 109 from an annular illuminating device 108 that surrounds the circumference of the optical axis 107 of FIG. In the bright field illumination method, the parallel light 111 from the light source 110 is transmitted through the beam splitter 112 to the optical axis 107 of the CCD camera 105.
This is an illumination method in which parallel light 111 is vertically irradiated onto the chip surface 102a so as to be coaxial with. FIG. 10 shows some examples of bump images obtained under the dark-field illumination method and the bright-field illumination method. In the figure, (i) is a plan view of a good bump, and (ii), (iii ) Is a plan view of a bump with a defective shape and a bump with a part missing, respectively.

In this conventional bump appearance inspection apparatus, the table 103 is movable in the x-axis and y-axis directions by the table controller 104, and the field of view of the CCD camera 105 is moved by moving the table 103. It has become.

FIG. 11 shows another conventional bump appearance inspection apparatus. This device is known as an in-line four-view optical barrel, and the chip 10 passing through a lens 201 is used.
2a, 202b, 2
A plurality of prisms 203 are arranged so as to be branched into four of 02c and 202d, and the four branch optical paths 202 are also provided.
As shown in FIG. 12, four cameras 205 are provided so as to be displaced from each other so as to receive light traveling through a, 202b, 202c and 202d, that is, so as to image each part of the chip 102. Lined up in 4
Each part of the chip in each of the two visual fields A, B, C, and D can be enlarged to some extent (1.2 times) for simultaneous observation. This allows the system to batch test long chips.

[0006]

The above-mentioned first conventional technique, which determines whether the bump 101 is good or bad by using the dark field illumination method and the bright field illumination method, is easily defective due to the following reason. There is a problem that the feature cannot be detected. That is,
In this conventional technique, the feature extraction is performed by binarizing the image data. In this case, even if the original image is preprocessed to remove noise, the annular shape in the conventional technique is used. In the dark field illumination method, even the wiring pattern directly under the bump is extracted. Therefore, since the bump and the wiring pattern overlap with each other, it is difficult to accurately determine the bump shape. This will be described in more detail. In the annular dark-field illumination method, since the light is applied to the chip surface 102a in an oblique direction, the irradiation light is scattered on the uneven portion, and a part of the light is received by the CCD camera 105. Since the light is incident vertically on the bump surface, the surface of the bump is bright and the pattern of the flat portion of the chip where no bump is present is observed dark. Although this illumination method can remove a part of the pattern of the flat part where the bump does not exist, conversely, as shown in FIG. 6A, a wiring pattern having minute irregularities other than the bump is also extracted. It will be done.

On the other hand, in the bright-field illumination method of irradiating the object vertically, the light incident on the convex bump 101 is scattered and the surface is observed dark, and the pattern of the flat portion of the chip other than the bump portion is observed. Is observed brightly, the pattern of this bright flat portion becomes an obstacle to extraction of the bump pattern.

Further, in the above first prior art,
Since only one CCD camera 105 is used to capture an image of the chip surface, when the chip 102 is long, it is not possible to capture an image of the entire surface of the chip 102 at one time. In this case, if you try to inspect the entire surface of the chip,
It is necessary to move the field of view by moving the table 103 by the table controller 104. Then, every time the visual field is moved, it is necessary to operate the table 103 to perform the chip position correction process, and there is also a problem that the processing time becomes long in proportion to the number of visual fields.

On the other hand, in the case of the second prior art, that is, in the case of the serial 4-field optical barrel, the four field-of-views A arranged in a straight line,
B, C, and D can be observed simultaneously, and the field of view pitch can be widened within a certain range. Therefore, as long as the image is taken at a predetermined magnification, a long chip can be viewed at once. It can be imaged. Therefore, the above-mentioned problem in the first conventional technique described above is solved by the second conventional technique. However,
Since this apparatus has only four fields of view and the total field of view is limited to 20 mm, when the magnification of the lens 201 is increased to a high magnification, it is possible to collectively image the entire surface of a long chip. There is a problem that you cannot do it. Therefore, if the entire length of the chip is to be imaged at a high magnification, the field of view needs to be expanded. However, considering the field of view expansion by this conventional technique, the number of branches of the optical path 202 is increased by the additional prism 203 ′.
The additional CCD camera 205 'will be used for imaging. Since the brightness of the reflected light from the chip 102 decreases every time it passes through the prism 203, the brightness of the light passing through the additional prism 203 ′ further decreases. And each CCD camera 20
Since the number of prisms that must pass through to reach 5,205 'varies depending on each visual field, a large luminance difference, that is, uneven illumination occurs in each visual field, resulting in image recognition being impossible (FIG. 5A). reference).

Therefore, it is an object of the present invention to obtain an image of the entire surface of a chip even with a long chip, without uneven illumination, and with a wiring pattern removed at a high magnification. It is an object of the present invention to provide a bump appearance inspection device capable of performing inspection at high speed and accurately.

[0011]

In order to achieve the above object, a bump visual inspection apparatus according to a first aspect of the present invention includes a supporting means for supporting a chip on which a bump to be inspected is formed, and a supporting means for supporting the chip. Illuminating means for illuminating the entire surface of the chip, a lens for enlarging an image obtained by reflected light from the entire surface of the chip, and a plurality of prisms arranged so as to divide the optical path of the light passing through the lens into a plurality of prisms. , Each of the imaging units is arranged between the plurality of imaging units that capture the light of each of the branched optical paths and the prism and each of the imaging units so that light is incident on each of the imaging units with a substantially equal amount of light. An image for determining the quality of the bump based on the image data obtained by performing image processing by inputting the image signal output from each of the image capturing units and a filter for adjusting the amount of incident light to And a management device, the lighting means
Between the light emitting element and the light emitting element and the supporting means.
With a diffusion lens provided, the outer periphery of the chip surface
It is characterized by an annular illuminating device that illuminates brightly and darkly the center .

[0012] In this bump appearance inspection apparatus, first, the chip is supported by the supporting means, the annular
The entire surface of the chip is illuminated by the illumination means including the illumination device . Then, after the illumination light reflected by the entire surface of the chip enters the lens, it travels to each imaging unit through the optical path branched by the plurality of prisms. Since the light amount of the light directed to each image pickup unit is adjusted by the filter before entering the image pickup unit, the light is incident on all the image pickup units with substantially the same light amount regardless of the number of prisms passing through. As a result, a magnified image of the entire surface of the chip without illumination unevenness can be collectively obtained. According to the present invention, a large number of fields of view can be prepared in advance by increasing the number of optical path branches, and a high magnification of a long chip (for example, 2.
It is also possible to deal with collective imaging at 5 magnifications. Even if the number of branches of the optical path is large, the amount of light is adjusted by the filter, so that uneven illumination does not occur. The amount of light reflected from the entire surface of the chip is reduced by passing through a plurality of prisms. Therefore, it is necessary to determine the amount of light emitted by the illumination means in consideration of the reduction in the amount of light.

[0013]

Usually, the bumps are provided on the outer peripheral portion of the chip. The ring-shaped illumination device according to claim 1 is an inspection target because it uses a diffusion lens to illuminate a chip outer peripheral portion where bumps are present brightly and a chip central portion where bumps are not present dark. The image of the bump can be effectively obtained.

[0015]

[0016]

The bump visual inspection device according to claim 2 is
Supporting means for supporting the chip on which bumps to be inspected are formed, illuminating means for illuminating the entire surface of the chip supported by the supporting means, and reflected light from the entire surface of the chip, A filter for removing the reflected light component, a lens for enlarging the image obtained by the reflected light from the entire surface of the chip, a plurality of prisms arranged to branch the optical path of the light passing through the lens into a plurality of, A plurality of imaging units that capture the light of the branched optical paths, and are disposed between the prism and each imaging unit, to each imaging unit, so that light is incident on any imaging unit with a substantially equal amount of light. A filter for adjusting the amount of incident light, and image processing is performed by inputting the image signal output from each of the image pickup units,
An image processing device for determining the quality of the bump based on image data obtained by image processing.

According to the second aspect of the invention, the light from which the reflected light component from the wiring pattern is removed is input to the image pickup device, so that an image of only the bumps without the wiring pattern can be obtained. Moreover, even if a part of the wiring pattern is captured, it is negligible and does not hinder the bump inspection. Therefore,
Easy and accurate determination of good and bad bumps.

[0019] In one embodiment <br/> bump appearance inspection apparatus of the present invention, the imaging unit is an odd number, the plurality of prisms is branched light path an odd number.

In order to image the entire chip with a plurality of image pickup units, it is necessary to determine which image pickup unit should be divided to image the entire chip according to the chip length. Since there is always an imaging unit located at the center, the imaging unit corresponding to the chip length is selected with the coordinate center of the imaging unit located at this center as the center of the chip. Further, when the supporting means is movable so that the position of the chip can be moved, the supporting means is moved (including rotation) around the center coordinates of the image pickup unit located at the center.

[0021] In the bump appearance inspection apparatus according to claim 3, the image processing apparatus, optionally a storage unit, an input image signal to store the position information and the position information of the bumps on the reference chip reference chip Of the chip based on the switching means for switching to the input from the image pickup part, and the image signal from the image pickup part located at the positions corresponding to both ends of the chip supported by the supporting means and the position information of the reference chip. It is characterized by further comprising a calculating means for recognizing the position of the chip to be inspected by calculating the amount of deviation and the inclination in the x- and y-axis directions from the position of the reference chip.

The image processing apparatus of this bump appearance inspection apparatus recognizes the position of the chip supported at any position by the supporting means as follows. First, the switching means sequentially switches to the image pickup units located at the positions corresponding to both ends of the chip to capture the image signals at both ends of the chip. Subsequently, based on the captured image signal and the position information of the reference chip, the amount of displacement and the inclination of the chip in the x and y axis directions from the position of the reference chip are calculated by the calculating means. Then, this calculated x,
The position of the chip is recognized from the shift amount and the inclination in the y-axis direction. Since the conventional device shown in FIG. 8 has only one imaging unit, and thus one visual field,
In order to image each end of the chip, it is necessary to move the table on which the chip is placed so that each end is in the visual field. On the other hand, according to the present invention, the image of each end portion of the chip can be taken in only by switching the image pickup unit by the switching unit, so that the position of the chip can be recognized at high speed.

Further, in the bump appearance inspection apparatus according to claim 4, the image processing apparatus converts the position of the bumps on the reference chip by using the shift amount and the slope determined by the calculating means The converting means, the extracting means for extracting the characteristic amount of the bump to be inspected existing at the position after the conversion, and the characteristic amount extracted by the extracting means are compared with a predetermined reference value, and the inspecting object is determined according to the comparison result. It is characterized by further comprising a judging means for judging whether the bump is good or bad.

In the image recognition device of this bump appearance inspection device, the position of the bump on the reference chip is registered in advance in the storage means, and the position of the bump on the reference chip is
The actual position of the bump can be recognized only by converting by the converting means using the displacement amount and the inclination obtained by the calculating means. That is, bump position recognition is performed at high speed. Therefore, high-speed inspection is possible.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 shows the entire structure of the bump appearance inspection apparatus according to the first embodiment. As shown in the figure, the bump appearance inspection apparatus 1 includes a support base 3 having a stage 2 for mounting a chip 102 on its upper surface, and a 9-optical path optical unit supported by a support 5 on the support base 3. 6, an annular illumination device 7 installed in the light receiving portion of the optical unit 6, and an image processing device 9 to which an output signal, that is, an image signal from the optical unit 6 is input via a video line 8. ing.

The stage 2 is movable in the x-axis and y-axis directions and rotatable (rotation angle θ) by a stage driving device (not shown).

Further, the image processing apparatus 9 includes an image processing / arithmetic unit 91 equipped with a memory storing a bump inspection program, a CPU for executing the program, and the like, and a monitor 92 for displaying the image-processed chip image. Consists of. The image processing / arithmetic unit 91 receives the output signal of the optical unit 6 and performs image processing to extract the characteristic value of the bump 101 from the image data of the chip 102 obtained through the image processing. Feature value,
Compared with a preset reference value, depending on the result,
The bumps are judged to be good or bad. As the image processing method and the feature value extracting method, known methods can be used, and since they are not directly related to the essence of the present invention, detailed description of these methods will be omitted.

The annular illumination device 7 and the optical unit 6 are constructed as shown in FIG. The annular illuminating device 7 includes a plurality of light emitting diodes (hereinafter, referred to as LEDs) 72, which are arranged inside the cover 71 at predetermined intervals in the circumferential direction and are inclined from the radially outer side toward the inner side, and the LEDs 72. And an annular diffusing lens 73 provided below. The diffusion lens 73 is an LED
After diffusing the light from 72, the chip 102 which is the subject
It is for illuminating so that the central part is dark and the outer peripheral part is bright. However, even if the central part is illuminated darkly, it is important to secure a sufficient amount of light as the amount of light for performing bump observation.

On the other hand, the optical unit 6 has a lens 61 for enlarging an image obtained by the reflected light from the chip 102 illuminated by the annular illumination device 7 and an optical path 62 of the light passing through the lens 61. A plurality of prisms 63 arranged so as to be branched into nine, and nine CCD cameras 65 (a, b, c, which receive light that has passed through the respective branch paths).
d, e, f, g, h). By enlarging the chip image by the lens 61 and the nine branches of the optical path 62 by the prism 63, a field of view approximately twice that of the second prior art can be realized, and therefore a long object can be magnified at a high magnification (for example, 2.5 times). However, batch imaging is possible, and high resolution (for example, 10
μ) can be processed.

Further, the input surface of each CCD camera 65 has an ND (neutral / neutral) for reducing the amount of incident light.
A density filter 66 is installed. This ND
The filter 66 adjusts the amount of light coming from the peripheral portion of the chip in accordance with the amount of light coming from the central portion of the chip so that the amount of light entering each CCD camera 65 becomes constant. CCD camera 65 by ND filter 66
It is possible to eliminate the brightness difference between the fields of view of the captured image, that is, the uneven illumination. 5A and 5B show images of respective visual fields taken by the CCD cameras a, c, e, g, and i when the light amount adjustment by the ND filter 66 is not performed and when it is performed. It can be seen that in the case of FIG. 5A, the difference in luminance between the visual fields is large, and in the case of FIG. 5B, the luminance of each visual field is substantially the same. The image state shown in FIG. 5 (A) corresponds to the image state when the field of view is expanded by simply providing the additional prism 203 'in the conventional technique shown in FIG.

A sharp cut filter 66 is provided between the lens 61 and the prism 63 to remove light in the wavelength region corresponding to the pigment component of the wiring pattern. Since the bump 101 on the chip 102 and the wiring pattern have different pigment components, by providing the sharp cut filter 66, an image of only the bump 101 from which the wiring pattern is removed can be obtained. In addition,
Actually, as shown in FIG. 6B, a part of the wiring pattern may remain slightly even by the sharp cut filter 66, but it does not affect extraction of the characteristic value of the bump. It is a thing. Therefore, it is possible to obtain the accurate feature value of the bump 101 from the image data of the binarized chip. By comparing with the image obtained by the conventional dark-field illumination method shown in FIG. 6A, it can be understood how the wiring pattern is removed from the image in this embodiment.

By the way, in the optical unit 6, an odd number (9 in this embodiment) of CCD cameras 65 are installed. There is a center camera (fifth camera in this case) for the odd number of cameras. The significance of this center camera will be described below with reference to FIG.

There are chips of various lengths, and it is necessary to determine which camera is to be divided into to capture images of the entire chip according to the chip length. As shown in FIG. 3 (A), when an odd number of cameras are arranged, a center camera exists therein, but a camera corresponding to the chip length is selected with the center of coordinates of this center camera as the chip center. This makes it easier to select a camera.

On the other hand, when an even number of cameras are arranged, the selection of the cameras becomes complicated and is not easy for the following reason. That is, when measuring an object existing at the boundary between the cameras, the field of view of each camera is as shown in FIG.
As shown in (B), a certain width (fixed width) w is overlapped in the x-axis direction, and this overlap width w is determined in consideration of the size of the object. When installing an even number of cameras, the boundary between the cameras becomes the chip center, and therefore the overlapping width w of the field of view must be taken into consideration when selecting the cameras, and therefore the selection of the cameras becomes complicated. Of.

Furthermore, in order to move (including rotation) the object 102 by moving the stage 2, it is necessary to align the center of the optical system with the center of the movement of the stage 2. By arranging it,
As shown in (C), the center coordinates of the center camera can be used as the center of stage movement, which facilitates position adjustment and operation of the stage 2.

FIG. 4 shows a flow of the bump inspection processing program executed by the image processing / arithmetic unit 91. The bump inspection processing program will be described below with reference to FIG.

First, in step # 1, the coordinates of the left and right chip corners of the reference chip and the bump barycentric coordinates of each visual field in the reference chip are registered as initial data. Next, in step # 2, after the chip 102 having bumps to be inspected is transferred onto the stage 2, the stage 2 is driven to align the position of the chip 102 with the light receiving surface of the optical unit 6. Next, in steps # 3 to 6,
The CCD cameras 65 are sequentially switched to the visual fields located at the left chip corner and the right chip corner, and the left and right chip corner coordinates are extracted from the captured image. Continued Step # 7
Then, the coordinates of the left and right chip corners extracted in steps # 4 and # 6 are compared with the coordinates of the left and right chip corners of the reference chip registered in step # 1, and the x and y-axis directions from the reference chip registration position are compared. The deviation amount (XY) and the inclination (θ) are calculated.

Next, in step # 8, the camera is switched again to the CCD camera 65 at the left chip corner position, and in steps # 9 to 11, the inspection is performed in the corresponding visual field. And
Until it is determined in step # 12 that the inspection of the entire visual field is completed, that is, the inspection of the visual field in which the right chip corner is located is completed, the CCD camera 65 is sequentially switched in step # 13 while moving the visual field. Perform an inspection.
In each visual field, in step # 9, the position conversion of the bump barycentric coordinates in each visual field of the registered reference chip is performed based on the displacement amount (XY) and the inclination (θ) obtained in step # 7. Determine the position of the bump to be inspected. Then, in step # 10, various feature values (area, etc.) of the bump at the determined position are extracted from the binary image data, and the extracted feature value is compared with a preset reference value to obtain the bump value. It is judged whether it is good or bad.

The above steps # 3, # 5, # 8, #
The switching means is constituted by 13. Further, the calculation means is constituted by the steps # 4, # 6 and # 7. Further, the step # 10 constitutes the extraction means, and the step # 11 constitutes the judgment means.

As is clear from the above description, in the present embodiment, the position determination of the chip and the movement of the visual field for the inspection are performed by switching the CCD cameras, not by driving the stage. Therefore, the bump appearance inspection process can be performed at high speed.

Although the bump visual inspection apparatus 1 shown in FIGS. 1 and 2 uses the annular illumination device 7 for chip illumination, the illumination device 4 shown in FIG. 7 can also be used. This lighting device 4
Is composed of four rectangular illuminating parts 40, and each illuminating part 40 has a structure in which an LED 42 is installed in a rectangular box-shaped cover 41. These four rectangular illuminators 40 are inclined parallel to each chip side and outward from the chip surface so that the entire surface of the chip mounted on the stage 2 can be uniformly illuminated. In this state, it is attached to an attachment portion (not shown). The length of the illumination unit 40 in the longitudinal direction is substantially equal to the length of each side of the stage 2. The illuminating device 4 can uniformly illuminate the entire surface of the chip 102, and can provide a sufficient amount of light for observing the bump 101 even in a low-luminance visual field in which the number of optical paths in the prism 63 is largest. Therefore, as in the case of the annular illumination device 7, the light amount can be adjusted by the ND filter 66,
An image effective for bump visual inspection can be obtained.

Further, in the bump appearance inspection apparatus 1 shown in FIGS. 1 and 2, the sharp cut filter 67 is used as a means for removing the wiring pattern from the image. The same effect can be obtained by transmitting only the phase light.
That is, the flat portion of the chip surface where the bumps 101 do not exist is a mirror surface, but the surface of the bump 101 is rough due to particles, so that the illumination light is specularly reflected on the chip flat portion surface and scattered on the bump surface. Therefore, the reflected light from the chip has a phase difference between the flat portion of the chip and the bump. By using this phase difference, the specular reflection light is removed by the polarization filter and only the scattered light is transmitted, so that the wiring pattern of the chip can be removed from the image, and the image of only the bump can be obtained. is there.

In the above embodiment, the optical path is branched into nine so that the nine fields of view can be imaged together, but the number of fields of view is not limited to this. Further, the number of CCD cameras 65 may be even.

[0045]

As is apparent from the above, the bump appearance inspection apparatus according to the first aspect of the present invention includes the support means for supporting the chip on which the bump to be inspected is formed, and the entire surface of the chip supported by the support means. Illuminating means for illuminating, a lens for enlarging an image obtained by reflected light from the entire surface of the chip, a plurality of prisms arranged to divide the optical path of light passing through the lens into a plurality of, A plurality of image capturing units that capture the light of each optical path, and the incident light to each image capturing unit are arranged between the prism and each image capturing unit so that the light is incident on each of the image capturing units with a substantially equal amount of light. A filter for adjusting the amount of light and an image processing device that inputs image signals output from each of the imaging units to perform image processing and determines pass / fail of the bumps based on image data obtained by the image processing. Equipment Since it is, it can be obtained collectively enlarged image with no illumination unevenness entire chip surface. Further, according to the invention of claim 1, the number of imaging units can be increased according to the chip length, batch imaging at a high magnification of a long chip can be dealt with, and high resolution processing can be performed. Further, even if the number of image capturing units, that is, the number of optical path branches is large, the amount of light incident on the image capturing units is adjusted by the filter, so that it is possible to effectively prevent uneven illumination.

That is, according to the invention of claim 1, FIG.
Since the uneven illumination as in the conventional apparatus shown in FIG. 8 is eliminated, the image can be surely recognized, and the processing time due to the movement of the table at the time of capturing the image of the entire surface of the chip as in the conventional apparatus shown in FIG. Because there is no loss,
Bump visual inspection can be performed stably at high speed.
And the device of the present invention, by a stable and high-speed inspection,
It becomes a device that replaces the visual appearance inspection process, and the inspection process can be automated.

[0047] In addition, in the bump appearance inspection apparatus according to claim 1, said illuminating means comprises a light emitting element, the light emitting element
And a diffusion lens provided between the support means and
Since it consists of an annular illuminating device that illuminates the outer peripheral part of the chip surface brightly and illuminates the central part darkly, it is possible to effectively illuminate the place with bumps and effectively obtain an image of the bumps to be inspected. be able to.

[0048]

The bump appearance inspection apparatus according to claim 2 is
Supporting means for supporting the chip having bumps to be inspected, illuminating means for illuminating the entire surface of the chip supported by the supporting means, and a lens for enlarging an image obtained by reflected light from the entire surface of the chip. A plurality of prisms arranged so as to divide the optical path of the light passing through the lens into a plurality of portions, a plurality of image capturing units that capture the light of the respective branched optical paths, and between the prism and each image capturing unit. And a filter that adjusts the amount of light incident on each image pickup unit so that the light is incident on each of the image pickup units at a substantially equal amount.
In addition to the image processing device that inputs the image signal output from each of the image pickup units and performs image processing, and determines the quality of the bump based on the image data obtained by the image processing, the reflected light from the entire surface of the chip Therefore, since a filter for removing the reflected light component from the wiring pattern on the chip surface is further provided, a bump image in which the wiring pattern is substantially removed can be obtained. Therefore, it is possible to easily and accurately determine whether the bump is good or bad.

[0050]

In the bump appearance inspection apparatus according to the third aspect of the present invention, since the image processing apparatus has a switching means for switching the input of the image signal to the input from an arbitrary image pickup unit, the image of each end of the chip can be displayed. Incorporation can be performed simply by switching the image pickup unit, and it is not necessary to move the table for supporting the chip unlike the conventional case. Therefore, the position of the chip supported at any position by the supporting means can be recognized at high speed. , Can be confirmed. Therefore, the appearance inspection of the chip can be performed at a higher speed in combination with the speedup of the inspection due to the ability to image the entire chip at once.

Further, in the bump appearance inspection apparatus according to the fourth aspect , the image processing apparatus converts the position of the bump on the reference chip by using the shift amount and the inclination obtained by the calculating means. Since the conversion means is provided, the actual bump position recognition can be performed at high speed. Therefore, the inspection can be performed at a higher speed in combination with the fact that the entire chip can be collectively imaged and the inspection can be speeded up, and the image signal can be input only by switching the image pickup unit.

[Brief description of drawings]

FIG. 1 is a system structure diagram of a bump appearance inspection device according to an embodiment of the present invention.

FIG. 2 is a structural diagram of an optical unit of the bump appearance inspection device of FIG.

FIG. 3 is a diagram illustrating the significance of a center camera in an optical unit.

FIG. 4 is a flowchart of an inspection processing program executed in the bump appearance inspection apparatus of FIG.

5 is a photograph replacing a drawing showing a fine pattern formed on a substrate, (A) is a photograph with uneven illumination obtained when a field of view is expanded according to a conventional method, and (B) is a photograph of FIG. It is a photograph that eliminates the illumination unevenness obtained by the optical unit.

6A is a schematic diagram of a chip image in which a wiring pattern is extracted by dark-field illumination, and FIG. 6B is a schematic diagram of a chip image in which the wiring pattern is removed using a sharp cut filter.

FIG. 7 is a diagram showing an illumination means different from the illumination device shown in FIGS.

FIG. 8 is a system configuration diagram of a conventional bump inspection apparatus.

FIG. 9 is a diagram illustrating a dark field illumination method and a bright field illumination method used in the bump inspection apparatus of FIG.

FIG. 10 is a diagram showing an observation state of the appearance of bumps by a dark field illumination method and a bright field illumination method.

FIG. 11 is a structural diagram of a serial 4-view optical barrel that is a conventional device.

12 is a diagram showing the field of view of the camera of FIG.

[Explanation of symbols]

1 ... Bump appearance inspection device, 2 ... Stage, 3 ... Support base,
4 ... Illumination device, 6 ... Optical unit, 7 ... Annular illumination device,
9 ... Image processing device, 61 ... Lens, 62 ... Optical path, 63 ...
Prism, 65 ... CCD camera, 66 ... ND filter,
67 ... Sharp cut filter, 101 ... Bump, 10
2 ... Chip.

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-6-323824 (JP, A) JP-A-2-155249 (JP, A) JP-A-7-286968 (JP, A) JP-A-6- 273127 (JP, A) JP 3-189544 (JP, A) JP 63-32670 (JP, A) JP 6-258047 (JP, A) JP 63-304109 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01B 11/24 G06T 7/00

Claims (4)

(57) [Claims] 1. A support means for supporting a chip on which bumps to be inspected are formed, an illuminating means for illuminating the entire surface of the chip supported by the support means, and light obtained by reflected light from the entire surface of the chip. A lens for enlarging the image, a plurality of prisms arranged so as to branch the optical path of the light passing through the lens into a plurality, a plurality of imaging units for capturing the light of the branched optical paths, the prism and each A filter that is arranged between the image pickup units and adjusts the light amount of the incident light to each image pickup unit so that the light is incident on each of the image pickup units with a substantially equal light amount, and an image output from each of the image pickup units. An image processing device that inputs a signal to perform image processing and determines pass / fail of the bump based on image data obtained by the image processing, wherein the lighting means includes a light emitting element, the light emitting element, and the support. And a diffusion lens arranged between the means, brighten the outer peripheral portion of the chip surface, the bump appearance inspection apparatus characterized by comprising an annular illuminating device for illuminating darkened center. 2. A supporting means for supporting a chip on which bumps to be inspected are formed, an illuminating means for illuminating the entire surface of the chip supported by the supporting means, and reflected light from the entire surface of the chip on the surface of the chip. The filter that removes the reflected light component from the wiring pattern, the lens that magnifies the image obtained by the reflected light from the entire surface of the chip, and the optical path of the light that has passed through the lens are arranged so as to branch into a plurality of paths. It is arranged between a plurality of prisms, a plurality of image pickup units that capture the light of the branched optical paths, and between the prisms and the respective image pickup units so that light is incident on any of the image pickup units with a substantially equal amount of light. , A filter that adjusts the amount of light incident on each imaging unit, and image processing that is performed by inputting the image signal output from each imaging unit described above, based on the image data obtained by the image processing. Bump appearance inspection apparatus characterized by comprising a determining image processing apparatus acceptability of pump. 3. A bump appearance inspection apparatus according to claim 1 or 2, the image processing apparatus includes a storage means for storing position information and the position information of the bumps on the reference chip reference chip, the image signal Based on the switching means for switching the input to the input from the arbitrary image pickup section, the image signal from the image pickup section located at the positions corresponding to both ends of the chip supported by the support means, and the position information of the reference chip, A bump appearance inspection apparatus, comprising: a calculating unit that calculates a displacement amount and an inclination of the chip from the position of the reference chip in the x- and y-axis directions and recognizes the position of the chip. 4. The bump appearance inspection device according to claim 3 , wherein the image processing device converts the position of the bump on the reference chip by using the shift amount and the inclination obtained by the calculation means. The conversion means, the extraction means for extracting the feature amount of the bump to be inspected existing at the position after the conversion, the feature amount extracted by the extraction means is compared with a predetermined reference value, and the inspection target is determined according to the comparison result. A bump appearance inspection apparatus further comprising a judging unit for judging whether the bump is good or bad.