JP2006269597A - Method and apparatus for electronic component mounting state inspection - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic component mounting state inspection method or the like for inspecting a mounting state of electronic components from an impression of electrode pads caused at thermal compression bonding, that can automatically inspect the mounting state of the electronic components mounted on the electrode pads by the thermal compression bonding independently of the personal difference of inspection people. <P>SOLUTION: In the example of the electronic component mounting state inspection method disclosed herein, first an observation image of the electrode pads 10a via a transparent mount board 10 by a differential interference microscope 1 is obtained as electronic image data. Then image processing for emphasizing a border in a particular direction is applied to the obtained electronic image data to obtain an emphasis processing value of the impression. Thereafter, a pressing force applied at the thermal compression bonding is obtained from the impression emphasis processing value obtained as above, on the basis of a relationship prepared in advance between the pressing force applied at the thermal compression bonding and the impression emphasis processing value. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electronic component mounting state inspection method and an electronic component mounting state inspection device, and in particular, anisotropic conductive material containing conductive particles on electrode pads disposed on a transparent mounting substrate by thermocompression bonding. The present invention can be applied to an electronic component mounting state inspection method and an electronic component mounting state inspection device that inspects the mounting state of an electronic component from the impression of the electrode pad generated when mounting the electronic component through a film.

  2. Description of the Related Art Conventionally, a technique for mounting an electronic component on an electrode pad disposed on a transparent mounting substrate by thermocompression bonding via an anisotropic conductive film containing conductive particles has existed. Further, as a method for inspecting the mounting state of the electronic component mounted in this way, there are the following methods.

  When the electrode pad is transparent, there is a method for inspecting the mounting state of the electronic component by visually confirming the state of collapse of the conductive particles using an optical microscope.

  In addition, when the electrode pad is opaque, there is a method for inspecting the mounting state of the electronic component by observing an indentation formed by the conductive particles on the electrode pad during thermocompression bonding with a differential interference microscope (Patent Document). 1).

JP 2003-269934 A

  However, the method of visually checking the degree of crushing and indentation of conductive particles through a transparent mounting substrate through an optical microscope or differential interference microscope allows confirmation of the pressure applied during thermocompression bonding and the parallelism of the electronic component mounting state. Confirmation and so on depended on the inspector's senses. In such a visual inspection, the inspection result may vary depending on individual differences among the inspectors to be judged.

  Japanese Patent Application Laid-Open No. 2004-228561 describes that the mounting state of the electronic component can be automatically inspected, but does not describe the specific method.

  Therefore, the present invention can automatically inspect the mounting state of the electronic component mounted on the electrode pad by thermocompression bonding without depending on individual differences of the inspector, and an electronic component mounting state inspection method and An object is to provide an electronic component mounting state inspection apparatus.

  In order to achieve the above object, the electronic component mounting state inspection method according to claim 1 according to the present invention provides a conductive film containing conductive particles on an electrode pad disposed on a transparent mounting substrate by pressure bonding. In the electronic component mounting state inspection method for inspecting the mounting state of the electronic component from the indentation of the electrode pad generated when mounting the electronic component via (A) the electrode through the transparent mounting substrate by a differential interference microscope A step of obtaining an observation image of the pad as electronic image data; and (B) performing an image process for emphasizing a boundary in a specific direction on the electronic image data obtained in the step (A), thereby enhancing the indentation. A step of obtaining a value, and (C) a pre-prepared step obtained by the step (B) based on the relationship between the pressure applied during the crimping and the emphasis processing value of the indentation. From the enhancement values of the indentation, and determining the applied pressure during the crimping includes.

  The electronic component mounting state inspection apparatus according to claim 9 of the present invention mounts an electronic component on an electrode pad disposed on a transparent mounting substrate through a conductive film containing conductive particles by pressure bonding. In the electronic component mounting state inspection apparatus for inspecting the mounting state of the electronic component from the impression of the electrode pad generated at the time, a differential interference microscope, and an observation image of the electrode pad through the transparent mounting substrate by the differential interference microscope Is applied to the electronic image data, and the electronic image data is subjected to image processing for emphasizing a boundary in a specific direction to obtain an emphasis processing value for the indentation, An image processing device that obtains the applied pressure applied during the press-bonding from the enhanced processing value of the indentation based on the relationship between the applied pressure applied at the time and the enhanced processing value of the indentation. That.

  The electronic component mounting state inspection method according to claim 1 of the present invention occurs when an electronic component is mounted on an electrode pad disposed on a transparent mounting substrate by pressure bonding via a conductive film containing conductive particles. In the electronic component mounting state inspection method for inspecting the mounting state of the electronic component from the indentation of the electrode pad, (A) an observation image of the electrode pad through the transparent mounting substrate by a differential interference microscope is used as electronic image data (B) performing an image process for emphasizing a boundary in a specific direction on the electronic image data obtained in the step (A), and obtaining an emphasis processing value for the indentation; Based on the relationship between the applied pressure applied at the time of the crimping and the emphasis processing value of the indentation, the emphasis processing value of the indent determined in the step (B), A step of determining the applied pressure applied at the time of wearing, even when the electrode pad is opaque, from a differential interference microscopic image of the indentation formed on the electrode pad, quantitatively and uniquely The applied pressure during mounting can be obtained. As a result, it does not depend on individual differences of the inspector when obtaining the applied pressure at the time of mounting.

  Further, the electronic component mounting state inspection apparatus according to claim 9 is generated when the electronic component is mounted on the electrode pad disposed on the transparent mounting substrate by pressure bonding via the conductive film containing conductive particles. In the electronic component mounting state inspection apparatus for inspecting the mounting state of the electronic component from the indentation of the electrode pad, an observation image of the electrode pad through the transparent mounting substrate by the differential interference microscope and the differential interference microscope is an electronic image. The imaging device to be converted into data and image processing for emphasizing a boundary in a specific direction are performed on the electronic image data to obtain an emphasis processing value of the indentation. And an image processing device that obtains the applied pressure applied at the time of the crimping from the enhanced processing value of the indentation based on the relationship between the applied pressure and the enhanced processing value of the indentation. (Specifically, the quality of the pressure applied during mounting) component mounting state of can be inspected automatically and easily.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.

<Embodiment 1>
FIG. 1 is a diagram showing a configuration of an electronic component mounting state inspection apparatus according to the present embodiment.

  As shown in FIG. 1, the electronic component mounting state inspection apparatus includes a differential interference microscope 1, a CCD (Charge Coupled Device) camera 2, and an image processing apparatus 3.

  The CCD camera 2 is an imaging device that photoelectrically detects an image of an electrode pad or the like observed with the differential interference microscope 1. The CCD camera 2 is connected to the differential interference microscope 1, and on the other hand, the CCD camera 2 is connected to the image processing device 3 via a cable 4.

  Here, the differential interference microscope 1 divides the illumination light into two light beams by a special prism, and observes the sample with a three-dimensional effect that raises the sample with the interference color and contrast of light and dark caused by the interference of these lights. It is a microscope that can

  The image processing device 3 is a device that can perform each image processing described later in accordance with an image processing program.

  In the differential interference microscope 1, as shown in FIG. 1, the structure described below is observed.

  The structure is obtained by mounting an electronic component 11 such as a semiconductor element on a transparent mounting substrate 10. As a device having the transparent mounting substrate 10 on which the electronic component 11 is mounted, for example, there is a liquid crystal device or the like. In addition, this invention is not limited to the thing regarding the test | inspection of the said liquid crystal device, but if the electronic component 11 is mounted on the transparent mounting board 10 via the electrode pad 10a, it can test | inspect.

  An electrode pad 10 a is disposed on the transparent mounting substrate 10. Also, bumps 11 a are formed on the electronic component 11. The electronic component 11 is mounted on the mounting substrate 10 with the electrode pads 10a and the bumps 11a facing each other. Here, the electronic component 11 is mounted on the mounting substrate 10 by thermocompression bonding. In addition, the electronic component 11 is mounted on the mounting substrate 10 via an anisotropic conductive film (ACF) 12 including conductive particles 12a.

  Therefore, when the thermocompression treatment is performed, a plurality of indentations due to the conductive particles 12a or the like are generated on the electrode pad 10a.

  As shown in FIG. 1, the mounting substrate 10 on which the electronic component 11 is mounted has the back surface (surface opposite to the mounting side) of the mounting substrate 10 facing the objective lens of the differential interference microscope 1. Has been placed. Therefore, in the differential interference microscope 1, an image of the electrode pad 10 a is observed through the transparent mounting substrate 10.

  Next, the electronic component mounting state inspection method according to the present embodiment will be described based on the flowchart shown in FIG.

  First, a plurality of electrode pads 10a are observed using the differential interference microscope 1 (step S1). Here, the electrode pad 10 a is observed through the transparent mounting substrate 10.

  The CCD camera 2 captures the image of the electrode pad 10a obtained through the differential interference microscope 1 and detects it photoelectrically (that is, photoelectrically converts the differential interference microscope image into electronic image data) (step S2).

  Then, the image processing apparatus 3 captures the electronic data image created by the CCD camera 2 (step S3). The electronic data image captured by the image processing apparatus 3 is shown in FIG.

  As can be seen from the electronic data image in FIG. 3, the image includes a plurality of electrode pads 10a. In addition, a plurality of indentation images 21 caused by conductive particles or the like generated during the thermocompression treatment are formed in one electrode pad 10a.

  Here, as shown in FIG. 3, the indentation image 21 obtained through the differential interference microscope changes the strength of the contrast along a specific direction. Specifically, the contrast (brightness) is weak at the lower left side of the impression image 21 (black portion), and the contrast (brightness) is strong at the upper right side of the impression image 21 (white portion). Although not clearly shown in FIG. 3, the contrast (luminance) of the impression image 21 is higher than the contrast (luminance) of the electrode pad 10a image.

  From the following, a series of image processing in the image processing apparatus 3 is executed.

  First, the image processing apparatus 3 executes an enhancement process for enhancing a contrast boundary described below (step S4).

  In step S4, an emphasis process for emphasizing the contrast strength boundary of the impression image 21 is performed at each pixel constituting the electronic data image shown in FIG. Then, as a result of the enhancement process, an enhancement process value (which can also be grasped as the luminance value of the image after the enhancement process) is obtained for each pixel. In the present embodiment, since the enhancement processing value is obtained by a predetermined calculation, it is hereinafter referred to as an enhancement processing calculation value.

  That is, as shown in FIG. 3, the contrast of the impression image 21 changes along a specific direction (the arrow direction in FIG. 3). Therefore, the enhancement processing in step S4 is performed using the following enhancement filter. Here, the enhancement filter can enhance the boundary of the contrast of the impression image 21 for each pixel constituting the electronic data image shown in FIG. 3, and depends on the specific direction. ing.

  Note that enhancement processing for enhancing the boundary of contrast includes primary differentiation processing, smoothing filter processing, Sobel filter processing, Laplacian filter processing, and the like.

  An example of the enhancement filter is shown in FIG. An example of enhancement processing using the enhancement filter shown in FIG. 4 will be described below. In FIG. 4, the coefficients f1, f2, and f5 can be positive numbers, and the coefficients f3, f6, and f7 can be negative numbers.

  The electronic data image shown in FIG. 3 includes a plurality of pixels, and each pixel has a contrast value (luminance value). FIG. 5 is a diagram showing some pixels (predetermined 9 pixels) of the image shown in FIG. Each pixel has a contrast value of b0 to b8.

  Now, attention is focused on a pixel having a contrast value b4. A case where the enhancement process using the enhancement filter shown in FIG. 4 is performed on the pixel will be described. In the enhancement processing of this example, in addition to the enhancement filter shown in FIG. 4, some of the pixels (contrast value b0) shown in FIG. 5 centered on the pixel of interest (pixels having a contrast value b4). -B3 and pixels having b5-b8).

  First, an enhancement processing coefficient “(b4) ′ x” shown below is obtained by an enhancement filter.

(B4) 'x = b0.f0 + b3.f3 + b6.f6 + b2.f2 + b5.f5 + b8.f8
Next, the enhancement processing coefficient “(b4) ′ y” shown below is obtained by the enhancement filter.

(B4) 'y = b0 · f0 + b1 · f1 + b2 · f2 + b6 · f6 + b7 · f7 + b8 · f8
Based on the above result, the result of enhancement processing for the pixel having the contrast value b4 (that is, the enhancement processing calculation value b′4 of the pixel) is expressed by the following equation.

b′4 = [{(b4) ′ x} ² + {(b4) ′ y} ² ] ^1/2
The above enhancement processing is performed on each pixel constituting the electronic data image shown in FIG. 3 (emphasis processing calculation value is obtained).

  As described above, by performing the above enhancement process on the electronic data image shown in FIG. 3, the impression image 21 can be made clearer. The image after the enhancement process is shown in FIG.

  As shown in FIG. 6, the image of the impression 22 is clearly discriminated although there is contrast strength. The contrast changes for each impression 22 image because the depth of the impression formed on the electrode pad 10a is different.

  After the enhancement process, the image processing device 3 stores the image after the enhancement process shown in FIG. 6 (step S4).

  Next, an inspection area is set for one electrode pad 10a of the image after the enhancement process (step S5). 6 is an inspection area, and a plurality of impression images 22 are included in the inspection area. The inspection area is set by the inspector from the outside with respect to the image processing apparatus 3.

  Incidentally, as shown in FIG. 7, one indentation image 22 is usually composed of a plurality of pixels.

  Therefore, the image processing device 3 extracts a plurality of pixels constituting one indentation 22 image, and compares enhancement processing calculation values for each of the extracted pixels. Then, one pixel having an enhancement processing calculation value that is the maximum value is selected from the plurality of extracted pixels (step S6).

  If one pixel having the maximum emphasis processing calculation value in one indentation image 22 belonging to the inspection area is selected, then the next emphasis processing for the other indentation image 22 is maximized. One pixel having the calculated value is selected (step S6).

  In this way, for each indentation image 22 belonging to the inspection region, one pixel having an enhancement processing calculation value that is the maximum value is selected (step S6).

  Next, the image processing device 3 obtains an average value (average enhancement processing calculation value) from the enhancement processing calculation value that is the maximum value of each pixel selected for each impression image 22 in step S6 (step S7). Then, the average enhancement processing calculation value is set as a representative value of the electrode pad 10a in which the inspection region is set.

  Next, the image processing device 3 determines whether or not the average enhancement processing calculation value has been obtained for all the electrode pads 10a included in the image data after the enhancement processing (FIG. 6) (step S8). .

  If the average emphasis processing calculation value has not been obtained for all the electrode pads 10a ("No" in step S8), the process returns to step S5, and the electrode pad 10a for which the average emphasis processing calculation value has not yet been obtained. On the other hand, a new inspection area is set. And the process after step S6 is performed again.

  On the other hand, if the average emphasis processing calculation value is obtained for all the electrode pads 10a (“Yes” in step S8), the process proceeds to step S9.

  Incidentally, the data shown in FIGS. 8 and 9 is stored in the image processing apparatus 3 in advance. 8 and 9 are data showing the relationship between the pressure applied during thermocompression bonding and the emphasis processing calculation value. Here, the horizontal axis is the applied pressure, and the vertical axis is the enhancement processing calculation value.

  The inventor has a relationship in which the enhancement processing calculation value increases primarily as the pressure increases (FIG. 8) and a relationship in which the enhancement processing calculation value decreases primarily as the pressure increases (FIG. 9). Found that there is. Which relationship belongs to the relationship is determined by, for example, the material of the electrode pad 10a. Moreover, even if it is the emphasis process calculation value obtained from the result of any emphasis process, it has the tendency shown to FIG.

  The inspector prepares data as shown in FIG. 8 or FIG. 9 using a sample prepared under the same conditions as the inspection object before the inspection. Then, the created data is stored in the image processing device 3 in advance.

  Next, the image processing apparatus 3 selects an average enhancement processing calculation value that is an extreme value from the average enhancement processing calculation values for each electrode pad 10a obtained by the processing up to step S8. Then, by referring to the data shown in FIGS. 8 and 9, a pressing force (the pressing force is referred to as mounting pressing force) with respect to the selected average emphasis processing calculation value that is the extreme value is obtained (step S <b> 9).

  Here, if the inspection target shows the relationship between the applied pressure and the enhancement processing calculation value shown in FIG. 8, the minimum average enhancement processing calculation value is selected from the plurality of average enhancement processing calculation values. Then, the mounting pressure is obtained from the data shown in FIG. 8 and the minimum average emphasis processing calculation value (step S9).

  On the other hand, if the object to be inspected shows the relationship between the applied pressure and the enhanced processing calculation value shown in FIG. 9, the maximum average enhanced processing calculated value is selected from the plurality of average enhanced processing calculated values. To do. Then, a mounting pressure is obtained from the data shown in FIG. 9 and the maximum average emphasis processing calculation value (step S9).

  That is, in step S9, the weakest pressure value at the time of thermocompression bonding is obtained from the inspection target.

  Next, the image processing apparatus 3 determines whether the electronic component 11 is mounted properly (that is, the mounting board 10 and the electronic component 11) from the pressure threshold value prepared in advance and the mounting pressure obtained in step S9. Is determined whether or not the continuity is good (step S10).

  If the applied pressure during mounting is larger than the applied pressure threshold (“Yes” in step S10), the mounting state of the electronic component 11 that is the inspection target (that is, the applied pressure during thermocompression bonding). Exceeds the predetermined value, and the electrical connection between the mounting substrate 10 and the electronic component 11 is determined to be “good (passed)” (step S11).

  On the other hand, if the applied pressure during mounting is equal to or less than the applied pressure threshold (“No” in step S10), the mounting state of the electronic component 11 that is the inspection target (that is, the applied pressure during thermocompression bonding) Is less than or equal to a predetermined value, and the continuity between the mounting substrate 10 and the electronic component 11 is determined to be “defective (failed)” (step S12).

  As described above, in the electronic component mounting state inspection method according to this embodiment, the differential interference microscope 1 is used, and the applied pressure at the time of mounting is determined based on the natural law shown in FIGS. The quality of the mounting state of the electronic component is determined from the mounting pressure.

  Therefore, the applied pressure during mounting can be quantitatively and uniquely obtained from the differential interference microscope image of the indentation formed on the opaque electrode pad 10a. As a result, it does not depend on individual differences of the inspector when obtaining the applied pressure at the time of mounting.

  In the above description, the average emphasis processing calculation value is obtained for each electrode pad 10a. However, the present invention is not limited to this, and a predetermined representative emphasis processing operation value is arbitrarily obtained for each electrode pad 10a. The inspection result may be determined using the enhancement processing calculation value that is an extreme value from the calculated enhancement processing calculation value.

  In the inspection method according to the present embodiment, a pressure threshold is prepared in advance, and the electronic component mounting state (between the mounting substrate 10 and the electronic component 11 is determined based on a comparison between the pressure threshold and the mounting pressure. Continuity) is determined.

  Therefore, it is possible to easily and automatically determine the quality of the electronic component mounting state (conduction between the mounting substrate 10 and the electronic component 11) without depending on individual differences among the inspectors.

  In addition, the electronic component mounting state inspection apparatus according to the present embodiment includes an image processing apparatus 3 capable of performing the above method.

  Therefore, it is possible to automatically inspect the mounting state of the electronic component (specifically, whether the pressure applied during mounting is good or bad).

  Further, in the present embodiment, the emphasis process for emphasizing the boundary between the contrast strengths is performed focusing on the fact that the contrast strength of the differential interference microscope image of the indentation changes along a specific direction.

  Therefore, in the image data, the background electrode pad image and the impression image can be differentiated more clearly.

  In the present embodiment, the case where the mounting pressure is obtained from the average emphasis processing calculation value that is an extreme value and the data shown in FIGS.

  However, for example, the corresponding pressurizing force may be obtained from the enhancement processing calculation value that is the maximum value selected in step S6 and the data shown in FIGS. In this case, it is also possible to obtain the applied pressure at the time of mounting on one indentation portion.

  Further, when a plurality of indentations are formed on the electrode pad 10a, a predetermined emphasis processing calculation value is obtained for each indentation, an average value is obtained from the obtained emphasis treatment calculation value, and the average value is used as the indentation emphasis processing. An inspection may be performed using the value.

  For example, the corresponding applied pressure may be obtained from the average emphasis processing calculation value obtained in step S7 and the data shown in FIGS. In this case, it is also possible to obtain an average mounting pressure in one electrode pad 10a.

<Embodiment 2>
In the electronic component mounting state inspection method according to the present embodiment, the inspection method according to Embodiment 1 is applied, and the parallelism of the electronic components in the mounting state can be inspected.

  FIG. 10 is a plan view of the liquid crystal display device as viewed from the outer surface side (the surface opposite to the mounting surface) of the transparent mounting substrate 10. In addition, since the electronic component 11 and the display unit 30 are formed on the inner surface side of the transparent mounting substrate 10, the outline is displayed with a dotted line. The electronic component 11 is a circuit that drives the display unit 30.

  Note that, as described above, the present invention is not limited to the one relating to the inspection of the liquid crystal device. If the electronic component 11 is mounted on the transparent mounting substrate 10 via the electrode pads 10a, the inspection is performed. Is possible.

  As shown in FIG. 10, a display unit 30 is provided on the inner surface of the mounting substrate 10. In addition, on the inner surface of the mounting substrate 10, a plurality of electronic components 11 are disposed on the outer periphery of the mounting substrate 10. Here, although not shown, the electronic component 11 is connected to a plurality of electrode pads 10a.

  By employing the inspection method according to the present embodiment, for example, the parallelism of the electronic component 11 in the mounted state shown in FIG. 10 can be inspected.

  Hereinafter, the electronic component mounting state inspection method according to the present embodiment will be described based on the flowchart shown in FIG. Here, the following description refers to a case where the parallelism is inspected for the electronic component 11q shown in FIG.

  FIG. 12 is a cross-sectional view showing a configuration around the electronic component 11q. 1 and 12 denote the same members. In FIG. 12, the conductive particles 12a contained in the anisotropic conductive film (ACF) 12 are not shown. As shown in FIG. 12, the electronic component 11 q is mounted with an inclination with respect to the mounting substrate 10.

  The configuration of the electronic component mounting state inspection apparatus is the same as that of the first embodiment, but the image processing apparatus 3 is loaded with a program that takes into account the following processes. Therefore, in the image processing apparatus 3 according to the present embodiment, image processing according to the installed program is automatically executed.

  First, as shown in FIG. 10, a first inspection region Q1 and a second inspection region Q2 are set for the electronic component 11q (step S21).

  The first inspection region Q1 is set so as to include one end portion of the electronic component 11q. The second inspection region Q2 is set so as to include the other end facing the one end of the electronic component 11q. By setting the inspection area, it is possible to inspect the parallelism of the electronic component 11q in the mounted state in the direction from the first inspection area Q1 to the second inspection area Q2.

  Therefore, when it is desired to check the parallelism in the direction to be inspected, the first inspection region Q1 and the second inspection region Q2 are set along the direction and are opposed to each other with a predetermined distance. Set it.

  Next, the process from step S1 to step S8 in FIG. 2 is executed for the first inspection region Q1. Through the series of processes, a mounting pressure in the first inspection region Q1 (hereinafter referred to as a first mounting pressure) is obtained (step S22).

  Next, the processing from step S1 to step S8 in FIG. 2 is executed for the second inspection region Q2. Through the series of processes, a mounting pressure (hereinafter referred to as a second mounting pressure) in the second inspection region Q2 is obtained (step S23).

  Next, a difference between the first mounting pressure and the second mounting pressure (hereinafter referred to as mounting pressure difference) is obtained (step S24).

  Next, the pressure difference threshold value prepared in advance is compared with the pressure difference during mounting (step S25).

  If the mounting pressure difference is smaller than the pressure difference threshold (“Yes” in step S25), both ends of the electronic component 11q (first inspection region Q1 and second inspection region Q2) The difference in the applied pressure during heat welding is within a predetermined range. Accordingly, the parallelism of the electronic component 11q in the mounted state can also be determined to be in a desired range, and it can be determined as “good (passed)” (step S26).

  On the other hand, if the mounting pressure difference is equal to or larger than the pressure difference threshold (“No” in step S25), both end portions of the electronic component 11q (the first inspection region Q1 and the second inspection region Q1). In the inspection region Q2), the difference in the applied pressure at the time of heat welding is outside the predetermined range. Therefore, it can be determined that the parallelism in the mounted state of the electronic component 11q is also outside the desired range, and can be determined as “defective (failed)” (step S27).

  As described above, in the electronic component mounting state inspection method according to the present embodiment, the first mounting pressure and the second mounting pressure are obtained quantitatively and uniquely, and further, from each of the pressures. The pressure difference during mounting is obtained.

  Therefore, it is possible to determine the degree of parallelism of the electronic component mounting state from the mounting pressure difference without depending on individual differences among the inspectors.

  In the inspection method according to the present embodiment, a pressure difference threshold is prepared in advance, and the parallelism of the electronic component mounting state is determined based on a comparison between the pressure difference threshold and the mounting pressure difference. ing.

  Accordingly, it is possible to easily determine whether or not the parallelism of the electronic component mounting state is good without depending on individual differences among inspectors.

  In addition, the electronic component mounting state inspection apparatus according to the present embodiment includes an image processing apparatus 3 capable of performing the above method.

  Therefore, it is possible to automatically inspect the mounting state of the electronic component (specifically, the parallelism of the electronic component 11q in the mounting state).

It is the schematic which shows the structure and test | inspection condition of the electronic component mounting state inspection apparatus which concern on this invention. 3 is a flowchart illustrating an electronic component mounting state inspection method according to the first embodiment. It is a figure which shows the electrode pad observed with a differential interference microscope. It is a figure for demonstrating an emphasis process. It is a figure for demonstrating an emphasis process. It is a figure which shows the electrode pad image after an emphasis process. It is a figure which shows a mode that indentation was comprised by the some pixel. It is one data which shows the relationship between a pressurizing force and an emphasis processing calculation value. It is the other data which shows the relationship between a pressurizing force and an emphasis process calculation value. It is a top view which shows the mode of the electrical components etc. which are mounted in the liquid crystal display device. 10 is a flowchart for explaining an electronic component mounting state inspection method according to the second embodiment. It is sectional drawing which shows a mode that the electronic component is mounted inclining with respect to the mounting substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Differential interference microscope, 2 CCD camera, 3 Image processing apparatus, 4 Cable, 10 Mounting board, 10a Electrode pad, 11, 11q Electronic component, 11a Bump, 12 Anisotropic conductive film (ACF), 12a Conductive particle, Q1 1st One inspection area, Q2 second inspection area, 30 display section.

Claims (9)

Electronic component that inspects the mounting state of the electronic component from the impression of the electrode pad that is generated when the electronic component is mounted on the electrode pad disposed on the transparent mounting substrate through the conductive film containing conductive particles by pressure bonding. In the mounting state inspection method,
(A) obtaining an observation image of the electrode pad through the transparent mounting substrate by a differential interference microscope as electronic image data;
(B) performing an image process for emphasizing a boundary in a specific direction on the electronic image data obtained in step (A), and obtaining an emphasis processing value for the indentation;
(C) From the enhancement processing value of the indentation obtained in the step (B) based on the relationship between the pressure applied during the pressure bonding and the enhancement processing value of the indentation prepared in advance. Obtaining a pressure applied during the crimping, and
An electronic component mounting state inspection method characterized by the above. The specific direction is
The contrast intensity of the image observed by the differential interference microscope is a direction that changes along the direction.
The electronic component mounting state inspection method according to claim 1. As an emphasis processing value of the indentation,
Using the maximum value of the emphasis processing value that each pixel of the indentation has,
The electronic component mounting state inspection method according to claim 2. A plurality of the indentations are formed on the electrode pad,
As an emphasis processing value of the indentation,
Using an average value obtained from a predetermined emphasis processing value obtained for each indentation,
The electronic component mounting state inspection method according to claim 2. The electrode pad is plural,
As an emphasis processing value of the indentation,
Using an emphasis processing value that is an extreme value obtained from a predetermined emphasis processing value obtained for each electrode pad,
The electronic component mounting state inspection method according to claim 2. (D) preparing a pressure force threshold value in advance;
(E) The method further includes the step of determining whether the electronic component is mounted properly from the pressure threshold and the pressure determined in step (C).
The electronic component mounting state inspection method according to claim 1. (O) setting a first inspection region and a second inspection region for the electronic component;
(P) performing the steps (A) to (C) on the first inspection region;
(Q) performing the steps (A) to (C) on the second inspection region;
(R) The method further comprises the step of obtaining a difference between the applied pressure determined in the step (P) and the applied pressure determined in the step (Q).
The electronic component mounting state inspection method according to claim 1. (S) preparing a pressure difference threshold value in advance;
(T) The method further includes the step of judging whether the electronic component is mounted or not based on the pressure difference threshold and the difference in the pressure obtained in step (R).
The electronic component mounting state inspection method according to claim 7. Electronic component that inspects the mounting state of the electronic component from the impression of the electrode pad that is generated when the electronic component is mounted on the electrode pad disposed on the transparent mounting substrate through the conductive film containing conductive particles by pressure bonding. In the mounting state inspection device,
Differential interference microscope,
An imaging device that converts an observation image of the electrode pad through the transparent mounting substrate by the differential interference microscope into electronic image data;
The electronic image data is subjected to image processing for emphasizing a boundary in a specific direction, an indentation emphasis processing value is obtained, and a preliminarily applied pressure applied during the pressure bonding and the indentation of the indentation are prepared. An image processing device for obtaining a pressure applied at the time of the pressure bonding from the enhancement processing value of the indentation based on a relationship with the enhancement processing value;
An electronic component mounting state inspection apparatus characterized by that.

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