Method for inspecting appearance of semiconductor chip and apparatus for inspecting appearance of semiconductor chip

Abstract

To provide a method for inspecting the appearance of a semiconductor chip and a device for inspecting the appearance of a semiconductor chip that can perform different processes on a semiconductor chip which is displaced by more than a threshold value.SOLUTION: The present invention includes the steps of: irradiating a semiconductor chip 48 arranged on a substrate with light and acquiring image data by reflected light from the semiconductor chip 48; and confirming whether at least one of the position and the amount of rotation of the semiconductor chip 48 is displaced by larger than a threshold value in the image data and determining that a different process from a process for the semiconductor chip within the threshold value is to be done if at least one of the position and the amount of rotation of the semiconductor chip 48 is displaced by more than the threshold value.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for inspecting the appearance of a semiconductor chip and an apparatus for inspecting the appearance of a semiconductor chip, and more particularly to an appearance inspection apparatus that acquires an image of a semiconductor chip to be inspected and performs an inspection.

Background Art

[0002] Conventionally, an appearance inspection apparatus that acquires an image of a semiconductor chip to be inspected and performs an inspection is known (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses an inspection apparatus that discriminates whether an inspection target is a non-defective product by comparing an image of an element chip of the inspection target taken with an image of a non-defective product and detects a defect of the element chip.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Although not described in Patent Document 1 mentioned above, when transferring a semiconductor chip on a wafer substrate to a transfer substrate, the semiconductor chip may rotate or the position of the semiconductor chip may shift. This is because the tip of the bump electrode of the semiconductor chip may be sharp or round. Therefore, even if the semiconductor chip is a good product, if it rotates or its position is shifted, when transferring from the transfer substrate to the wiring substrate, the semiconductor chip and the wiring position may not match, and the possibility that the semiconductor chip does not function increases. Therefore, even if the semiconductor chip transferred to the transfer substrate or the semiconductor chip transferred to the wiring substrate is a good product, for a semiconductor chip whose position has shifted beyond the threshold or whose rotation amount is large, it is desired to make a judgment to perform a process different from that of a semiconductor chip within the threshold.

[0006] This invention has been made to solve the above problems. One object of this invention is to provide an appearance inspection apparatus capable of making a judgment to perform a process different from that of a semiconductor chip within a threshold for a semiconductor chip whose position has shifted beyond the threshold.

Means for Solving the Problems

[0007] To achieve the above object, an appearance inspection method for a semiconductor chip according to a first aspect of this invention includes a step of irradiating light to a semiconductor chip disposed on a substrate and acquiring image data by reflected light from the semiconductor chip, and in the image data, checking whether at least one of the position of the semiconductor chip and the rotation amount of the semiconductor chip has shifted beyond a threshold, and if it has shifted beyond the threshold, making a judgment to perform a process different from that of a semiconductor chip within the threshold.

[0008] As described above, the method for inspecting the appearance of a semiconductor chip according to the first aspect of the present invention irradiates light onto the semiconductor chip disposed on the substrate to acquire image data of the semiconductor chip. From the acquired image data of the semiconductor chip, it can be confirmed that the semiconductor chip has rotated or deviated from its original position when at least one of the rotation amount and position of the semiconductor chip deviates beyond a threshold value. As a result, it is possible to make a determination to perform a process different from that for a semiconductor chip within the threshold value.

[0009] In the method for inspecting the appearance of a semiconductor chip according to the first aspect described above, preferably, in the step of performing a process different from that for a semiconductor chip within the threshold value, the different process is a process of determining not to use the semiconductor chip. With this configuration, when transferring the semiconductor chip onto the wiring substrate after transfer, a semiconductor chip with a high possibility of misaligned wiring positions is determined in advance not to be used without transfer.

[0010] In the method for inspecting the appearance of a semiconductor chip according to the first aspect described above, preferably, in the step of acquiring image data, light is irradiated onto the semiconductor chip while changing the illumination intensity, and a plurality of image data are acquired from the reflected light from the semiconductor chip at a plurality of illumination intensities. With this configuration, in a single image data, when there is a semiconductor chip with saturated pixel values, the rotation amount and positional deviation cannot be confirmed. However, by acquiring a plurality of image data from the reflected light from the semiconductor chip at a plurality of illumination intensities, it is possible to acquire the image data at each illumination intensity, so that the rotation amount and positional deviation of the semiconductor chip can be confirmed from the image data with unsaturated pixel values.

[0011] In this case, preferably, in the step of acquiring image data, light is irradiated onto the semiconductor chip from at least two directions, and image data are acquired from the reflected light from the semiconductor chip. With this configuration, even when there is a tilted semiconductor chip on the substrate, since the reflected light is incident on the imaging unit, it is possible to acquire image data in which the rotation amount and positional deviation can be confirmed.

[0012] In the configuration of irradiating the semiconductor chip with light from at least the above two directions, preferably, one of the above two directions is the vertical direction, and the other of the above two directions is the obliquely upward direction. With such a configuration, since the image data of a plurality of appropriately transferred semiconductor chips can be acquired by the light from the vertical direction, it is possible to determine whether to use the semiconductor chip or not. Also, since the image data of the inclined semiconductor chip can be acquired by the light from the obliquely upward direction even when the upper surface of the semiconductor chip is inclined obliquely with respect to the horizontal direction, it is possible to determine whether to perform a process different from that of the semiconductor chip within the threshold value.

[0013] In the configuration of irradiating the semiconductor chip with light from at least the above two directions, preferably, in the step of acquiring image data, the relative height of the irradiation portion of the light from the obliquely upward direction with respect to the substrate is changed, and the semiconductor chip is irradiated with light at each of a plurality of height positions, and a plurality of image data are acquired by the reflected light from the semiconductor chip at each of the plurality of height positions. With such a configuration, when there is a semiconductor chip with saturated pixel values, the amount of rotation and positional deviation cannot be confirmed. However, by changing the height of the irradiation portion of the light from the obliquely upward direction with respect to the substrate, the imaging unit can acquire image data in which the pixel values at each height are not saturated, so that the amount of rotation and positional deviation of the semiconductor chip can be confirmed.

[0014] In this case, preferably, in the step of determining to perform a process different from that of the semiconductor chip within the threshold value, the semiconductor chip is irradiated with a predetermined amount of light, image data is acquired by the reflected light from the semiconductor chip, and in the image data, when the reflected light from the inclined semiconductor chip is incident on the imaging unit excessively, the semiconductor chip with saturated pixel values is determined to perform a process different from that of the semiconductor chip within the threshold value. With such a configuration, when transferring the semiconductor chip from the transfer substrate to the wiring substrate, in advance, the semiconductor chip with a low probability of matching the wiring position will not be transferred, so that the working efficiency of the process of transferring the semiconductor chip to the wiring substrate can be improved.

[0015] An appearance inspection apparatus according to a second aspect of the present invention is an appearance inspection apparatus that inspects the position of a semiconductor chip disposed on a substrate and the amount of rotation of the semiconductor chip, respectively, and includes a substrate holding unit that holds the substrate on which the semiconductor chip is disposed, an irradiation unit that irradiates light onto the semiconductor chip of the substrate held by the substrate holding unit, an imaging unit that images the semiconductor chip to be inspected, and a control unit that determines whether at least one of the position of the semiconductor chip to be inspected imaged by the imaging unit and the amount of rotation of the semiconductor chip deviates beyond a threshold value, and when it deviates beyond the threshold value, controls to determine whether to perform a process different from that of the semiconductor chip within the threshold value on the semiconductor chip on the substrate.

[0016] As described above, the appearance inspection apparatus for a semiconductor chip according to the second aspect of the present invention acquires image data of the semiconductor chip by an irradiation unit that irradiates light onto the semiconductor chip disposed on the substrate held by the substrate holding unit and an imaging unit that images the semiconductor chip to be inspected. From the acquired image data of the semiconductor chip, the control unit obtains the amount of rotation and the position of the semiconductor chip, and by deviating beyond the threshold value, it can be confirmed that the semiconductor chip has rotated or deviated from its original position. As a result, it is possible to determine whether to perform a process different from that of the semiconductor chip within the threshold value on the semiconductor chip.

[0017] In the appearance inspection apparatus according to the second aspect, preferably, the irradiation unit irradiates light on the semiconductor chip from at least two directions, namely, the vertical direction and the obliquely upward direction, and further includes a relative lifting mechanism that changes the relative height between the substrate holding unit and the irradiation unit. The control unit is configured to control to change the height of the relative lifting mechanism when detecting a semiconductor chip whose pixel value is saturated by the reflected light from the semiconductor chip. With this configuration, when detecting a semiconductor chip whose pixel value is saturated by the reflected light from the semiconductor chip, the relative height between the irradiation unit and the semiconductor chip with respect to the substrate is changed by the relative lifting mechanism, and image data at each height can be acquired by the imaging unit. Therefore, it is possible to confirm the amount of rotation and the deviation of the position of the semiconductor chip from the image data in which the pixel value is not saturated.

[0018] In the appearance inspection apparatus according to the second aspect, preferably, when the control unit detects a semiconductor chip whose pixel value is saturated due to reflected light from the semiconductor chip, the control unit is configured to perform control to determine that a process different from that of the semiconductor chip within the threshold is to be performed on the semiconductor chip on the substrate. With this configuration, when transferring a semiconductor chip from a transfer substrate to a wiring substrate, in advance, for a semiconductor chip with a low probability of correct wiring position, a process different from that of the semiconductor chip within the threshold (semiconductor chip with a high probability of correct wiring position) is performed, so that the working efficiency of the process of transferring the semiconductor chip to the wiring substrate can be improved.

Effect of the Invention

[0019] According to the present invention, as described above, it is possible to provide an appearance inspection apparatus capable of determining whether to perform a process different from that of a semiconductor chip within a threshold on a semiconductor chip whose position deviates beyond the threshold.

Brief Description of the Drawings

[0020]

Figure 1

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Figure 8

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Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0021] Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

[0022] With reference to FIGS. 1 and 6, the appearance inspection method according to the present embodiment will be described.

[0023] [First Embodiment] (Structure of Appearance Inspection Apparatus) With reference to FIG. 1, the structure of the appearance inspection apparatus 100 according to the first embodiment will be described. The appearance inspection apparatus 100 is configured to inspect a plurality of semiconductor chips 48 (see FIGS. 2 to 5).

[0024] As shown in FIG. 1, the appearance inspection apparatus 100 includes a moving stage 10. The moving stage 10 includes an X-axis slider 11 and a Y-axis slider 12 in a horizontal plane. The X-axis slider 11 is disposed on the base 20. Further, the Y-axis slider 12 is disposed on the X-axis slider 11.

[0025] In addition, the appearance inspection device 100 includes a mounting table 30. The mounting table 30 is disposed on the Y-axis slider 12. And the mounting table 30 is configured to be moved in the X direction and the Y direction by the moving stage 10. Further, the mounting table 30 is configured to mount a transfer substrate 49 on which a plurality of semiconductor chips 48 are arranged. Note that the transfer substrate 49 is an example of the "substrate" in the claims.

[0026] In addition, the appearance inspection device 100 includes an imaging unit 40. The imaging unit 40 is configured to create image data of the semiconductor chip 48 to be inspected. The imaging unit 40 includes a lens barrel 41, a half mirror 42, an objective lens 43, and an imaging camera 44. The imaging camera 44 includes a light receiving element 44a. And the imaging camera 44 is configured to output the image of the imaged semiconductor chip 48 to a control unit 51 described later.

[0027] In addition, the appearance inspection device 100 includes an illumination unit 45. The illumination unit 45 includes a coaxial epi-illumination device 45a, and irradiates the semiconductor chip 48 below with irradiation light in a vertical direction from an irradiation unit 46a through the half mirror 42. The imaging unit 40 is configured to image the reflected light exiting from the semiconductor chip 48 in the vertical direction.

[0028] In addition, the appearance inspection device 100 includes a control unit 51. The control unit 51 is composed of a CPU (Central Processing Unit) or the like, and includes a data input unit 52, a storage unit 53, a detection unit 54, a data providing unit 55, and a data transmission unit 56. Also, the control unit 51 controls the illumination intensity of the illumination unit 45.

[0029] The data input unit 52 can input in advance the threshold values of the rotation amount and the positional deviation and the light amount.

[0030] Also, in the storage unit 53, the threshold values input by the data input unit 52 are stored.

[0031] The detection unit 54 detects the edges of the peripheral region of the semiconductor chip 48 and the edges of the bump electrodes 50 based on the image of the semiconductor chip 48 captured by the imaging unit 40. The detection unit 54 compares the image data of the semiconductor chip 48 captured by the imaging unit 40 with the position data of the aligned semiconductor chip 48 as shown in FIG. 2 pre-stored in the storage unit 53, and determines whether the amount of rotation and the positional deviation exceed the set threshold values.

[0032] When the amount of rotation or the positional deviation of the semiconductor chip 48 in the captured image data exceeds the threshold value, the data assigning unit 55 assigns data indicating that a process different from that of the semiconductor chip 48 within the threshold value is to be performed to the address assigned to the semiconductor chip 48. Specifically, the different process means that when the amount of rotation or the position deviates beyond the threshold value, the semiconductor chip 48 is not transferred to the wiring board and is not used. Note that the address of the semiconductor chip 48 is determined in advance as design information.

[0033] When transferring the semiconductor chip 48 on the transfer substrate 49 to the wiring board, the data transmission unit 56 transmits data indicating that the semiconductor chip 48 not to be transferred is not to be used in advance to the device that performs the transfer from the transfer substrate 49 to the wiring board.

[0034] Further, the appearance inspection device 100 includes a substrate transfer unit 57. When the inspection of the semiconductor chip 48 on the transfer substrate 49 is completed, the substrate transfer unit 57 sends the transfer substrate 49 to the device that performs the transfer in order to transfer the semiconductor chip 48 on the transfer substrate 49 from the transfer substrate 49 to the wiring board.

[0035] With reference to FIGS. 2 to 5, the transfer substrate 49 will be described. The semiconductor chip 48 is transferred onto the transfer substrate 49 from the wafer. The semiconductor chip 48 includes bump electrodes 50 (see FIG. 3). FIGS. 2 and 3 show the semiconductor chip 48 properly transferred. FIGS. 4 and 5 show the transferred semiconductor chip 48, including those that are rotated 48a, those that are misaligned 48b, and those that are tilted 48c.

[0036] (Appearance inspection method of the first embodiment) Next, the appearance inspection method of the first embodiment will be described. The appearance inspection method of the first embodiment is for obtaining the rotation amount and positional deviation of the semiconductor chip 48 on the transfer substrate 49 from the image data, and selecting in advance the semiconductor chips 48 that are not transferred to the wiring substrate from the transfer substrate 49 and not used.

[0037] In step 100 (see FIG. 6), the transfer substrate 49 is placed on the placement table 30 of the appearance inspection apparatus 100. In step 101, the threshold values, light quantity, and imaging method related to the rotation amount and positional deviation of the semiconductor chip 48 are input to the data input unit 52. In step 102, the irradiation unit 46 irradiates light onto the semiconductor chip 48. The imaging unit 40 images the semiconductor chip 48 with the light reflected from the semiconductor chip 48 and acquires image data. In step 103, the control unit 51 selects the address of the semiconductor chip 48. In step 104, the detection unit 54 extracts the semiconductor chip 48 at the address selected from the image data. In step 105, the detection unit 54 checks the rotation amount and positional deviation of the semiconductor chip 48. In step 106, if the rotation amount and positional deviation are equal to or greater than the set threshold value, in step 107, the data providing unit 55 provides a marker indicating that the address of the semiconductor chip 48 is not transferred to the wiring substrate and is not used, and the process proceeds to step 108. If the rotation amount and positional deviation of the semiconductor chip 48 are not equal to or greater than the set threshold value, the data providing unit 55 does not provide a marker indicating that the address of the semiconductor chip 48 is not transferred to the wiring substrate and is not used, and the process proceeds to step 109. In step 108, if there are unselected addresses, the process returns to step 103 and the steps from step 103 to step 108 are repeated. In step 108, when there are no unselected addresses left, in step 109, the detection unit 54 checks whether it can discriminate the image data of the semiconductor chip 48 from the image data. In step 109 above, when the detection unit 54 can discriminate the image of the semiconductor chip 48 at the selected address, in step 111, the data transmission unit 56 transmits the data assigned to the address to the apparatus that transfers the semiconductor chip 48 from the transfer substrate 49 to the wiring substrate. Also, the substrate transfer unit 57 sends the transfer substrate 49 to the apparatus that transfers the semiconductor chip 48 from the transfer substrate 49 to the wiring substrate.

[0038] In step 109 above, when the detection unit 54 fails to identify the image of the semiconductor chip 48 at the selected address, in step 110, the control unit 51 changes the illumination intensity and returns the process to step 102. The control unit 51 changes the illumination intensity until the detection unit 54 can identify the image of the semiconductor chip 48. When the detection unit 54 can identify the image of the semiconductor chip 48, the process proceeds to step 111.

[0039] (Effect of the First Embodiment) In the first embodiment, as described above, by irradiating the semiconductor chip 48 disposed on the transfer substrate 49 with light, image data of the semiconductor chip 48 is acquired. From the acquired image data of the semiconductor chip 48, it can be confirmed that at least one of the rotation amount and the position of the semiconductor chip 48 deviates beyond the threshold value, indicating that the semiconductor chip 48 has rotated or shifted from its original position. As a result, an appearance inspection method capable of determining whether to use the semiconductor chip 48 can be provided.

[0040] Also, in the first embodiment, as described above, in the step of performing a process different from that of the semiconductor chip 48 within the threshold value, the different process is a process of determining not to use the semiconductor chip 48. Thereby, when transferring the semiconductor chip 48 to the wiring substrate after transfer, it can be determined in advance not to use the semiconductor chip 48 that is highly likely to cause a shift in the wiring position without transferring it.

[0041] Further, in the first embodiment, as described above, in the step of acquiring image data, light is irradiated onto the semiconductor chip 48 while changing the illumination intensity, and a plurality of image data are acquired based on the reflected light from the semiconductor chip 48 at a plurality of illumination intensities. Thereby, in a single image data, when there is a semiconductor chip 48 with saturated pixel values, the rotation amount and position deviation cannot be confirmed. However, by acquiring a plurality of image data based on the reflected light from the semiconductor chip 48 at a plurality of irradiation intensities, image data at each illumination intensity can be acquired, so that the rotation amount and position deviation of the semiconductor chip 48 can be confirmed from the image data with unsaturated pixel values.

[0042] [Second Embodiment] (Structure of Appearance Inspection Device) Unlike the first embodiment, the appearance inspection device 200 according to the second embodiment of the present invention includes both the coaxial epi-illumination device 45a and the ring-shaped illumination device 45b of the illumination unit 45, as shown in FIG. 7. By including the ring-shaped illumination device 45b, the illumination unit 45 is configured to irradiate light from two directions, namely, the obliquely upward direction and the vertical direction, from the irradiation unit 46b. Note that the same components as those in the first embodiment are denoted by the same reference numerals in the drawings, and their descriptions are omitted.

[0043] FIG. 8 is a view of the ring-shaped illumination device 45b seen from below. The ring-shaped illumination device 45b installed below the objective lens 43 is provided with a plurality of LED light sources 47. Also, as shown in FIG. 2, the portion of the ring-shaped illumination device 45b where the LED light sources 47 are provided is inclined downward from the center toward the outer edge. The hole 63a penetrates so that the semiconductor chip 48 can be imaged.

[0044] The light irradiated from the obliquely upper direction by this ring-shaped illumination device 45b is reflected by the semiconductor chip 48. The imaging unit 40 captures image data from the reflected light. In the first embodiment, due to the coaxial epi-illumination device 45a, the reflected light from the obliquely inclined semiconductor chip 48c hardly enters the imaging unit 40. This is because the obliquely inclined semiconductor chip 48c reflects light obliquely. However, since the ring-shaped illumination device 45b irradiates light from the obliquely upper direction, the reflected light from the obliquely inclined semiconductor chip 48c is also configured to enter the imaging unit 40. Therefore, the amount of rotation and the positional deviation can be obtained from the image data of the obliquely inclined semiconductor chip 48c.

[0045] In addition, the ring-shaped lighting device 45b is configured to include a lighting elevator 58 so that the relative height with respect to the substrate holding portion can be changed. The lighting elevator 58 is an example of the "relative elevator mechanism" in the claims. When light reflected from the obliquely inclined semiconductor chip 48c is incident on the imaging unit 40 excessively, the pixel values of the image data of the semiconductor chip 48 become saturated (hereinafter referred to as saturation). Changing the relative height with respect to the substrate holding portion is to be able to eliminate saturation by changing the irradiation angle of light. When the image data of the semiconductor chip 48 is saturated, the control unit 51 can acquire an image of the non-saturated semiconductor chip 48 by changing the height of the ring-shaped lighting device 45b.

[0046] In addition, other configurations of the second embodiment are the same as those of the first embodiment described above.

[0047] (Appearance inspection method of the second embodiment) Next, the appearance inspection method of the second embodiment will be described. The appearance inspection method of the second embodiment is for acquiring the rotation amount and positional deviation of the semiconductor chip 48 on the transfer substrate 49 from the image data, and selecting a semiconductor chip 48 that performs a process different from that of the semiconductor chip 48 within a threshold value in advance. The different process is a process of determining not to use the semiconductor chip 48.

[0048] In step 200 (see FIG. 9), the transfer substrate 49 is placed on the placement table 30 of the appearance inspection apparatus 200. In step 201, a threshold value, light quantity, and imaging method related to the rotation amount and positional deviation of the semiconductor chip 48 are input to the data input unit 52. In step 202, the irradiation unit 46b irradiates light onto the semiconductor chip 48. The imaging unit 40 images the semiconductor chip 48 with the light reflected from the semiconductor chip 48 and acquires image data. In step 203, the control unit 51 selects the address of the semiconductor chip 48. In step 204, the detection unit 54 extracts the semiconductor chip 48 at the address selected from the image data. In step 205, the detection unit 54 checks the rotation amount and positional deviation of the semiconductor chip 48 from the image data. In step 206, when the rotation amount or positional deviation is equal to or greater than the set threshold value, in step 207, the data providing unit 55 provides a marker indicating that the semiconductor chip 48 is not transferred from the transfer substrate 49 to the wiring substrate and is not used, and the process proceeds to step 208. When the rotation amount and positional deviation are not equal to or greater than the set threshold value, the data providing unit 55 does not provide a marker indicating that the semiconductor chip 48 is not transferred from the transfer substrate 49 to the wiring substrate and is not used, and the process proceeds to step 208. In step 208, when there are unselected addresses, the process returns to step 203, and the steps from step 204 to step 208 are repeated. In step 208, when there are no unselected addresses, the process proceeds. Also, in step 209, the detection unit 54 determines whether the image data of the semiconductor chip 48 is saturated. In step 209, when the image data of the semiconductor chip 48 is not saturated, the process proceeds. In step 211, the data transmission unit 56 transmits the data assigned to the address to the apparatus that transfers the semiconductor chip 48 from the transfer substrate 49 to the wiring substrate. Also, the substrate transfer unit 57 sends the transfer substrate 49 to the apparatus that transfers the semiconductor chip 48 from the transfer substrate 49 to the wiring substrate.

[0049] In step 209 above, when the image data of the semiconductor chip 48 at the selected address is saturated, in step 210, the control unit 51 changes the height of the ring-shaped illumination device 45b by the illumination elevator 58 and returns the process to step 202. Until the image data of the selected semiconductor chip 48 stops being saturated, the height of the ring-shaped illumination device 45b is changed, and steps 202 to 209 are repeated until unsaturated image data of the selected semiconductor chip 48 can be acquired. When unsaturated image data of the selected semiconductor chip 48 can be acquired, the process proceeds to step 211.

[0050] (Effect of the Second Embodiment) In the second embodiment, the following effects can be obtained.

[0051] In the second embodiment, similar to the first embodiment above, by irradiating light onto the semiconductor chip 48 disposed on the transfer substrate 49, image data of the semiconductor chip 48 is acquired. From the acquired image data of the semiconductor chip 48, it can be confirmed that at least one of the rotation amount and the position of the semiconductor chip 48 deviates beyond a threshold value, so that the semiconductor chip 48 is rotating or is displaced from its original position. As a result, an appearance inspection method capable of determining whether to use the semiconductor chip 48 can be provided.

[0052] In the second embodiment, as described above, in the step of acquiring image data, light from at least two directions is irradiated onto the semiconductor chip 48, and image data is acquired by the reflected light from the semiconductor chip 48. Thereby, even when there is a semiconductor chip 48 tilted on the transfer substrate 49, since the reflected light is incident on the imaging unit 40, it is possible to acquire image data in which the rotation amount and the displacement of the position can be confirmed.

[0053] In the second embodiment, one of the two directions is the vertical direction, and the other of the two directions is the obliquely upward direction. Thereby, image data of a plurality of appropriately transferred semiconductor chips 48 can be acquired by light from the vertical direction, so that it is possible to determine whether or not to use the semiconductor chip 48. Further, even when the upper surface of the semiconductor chip 48 is inclined obliquely with respect to the horizontal direction by light from the obliquely upward direction, image data of the inclined semiconductor chip 48c can be acquired, so that it is possible to determine whether or not to use it.

[0054] Also, in the second embodiment, as described above, in the step of acquiring image data, the relative height of the irradiation unit 46b of the light from the obliquely upward direction with respect to the transfer substrate 49 is changed, and light is irradiated onto the semiconductor chip 48 at each of a plurality of height positions, and a plurality of image data are acquired by the reflected light from the semiconductor chip 48 at each of the plurality of height positions. Thereby, when there is a semiconductor chip 48 whose pixel value is saturated, the amount of rotation and the positional deviation cannot be confirmed. However, by changing the height of the irradiation unit 46b of the light from the obliquely upward direction with respect to the substrate, the imaging unit 40 can acquire image data in which the pixel values at each height are not saturated, so that the amount of rotation and the positional deviation of the semiconductor chip 48 can be confirmed.

[0055] Note that other effects of the second embodiment are the same as those of the first embodiment.

[0056] [Third Embodiment] (Structure of Appearance Inspection Device) The appearance inspection device 300 according to the second embodiment of the present invention includes both a coaxial epi-illumination device 45a and a dome-shaped illumination device 45c of the illumination unit 45, as shown in FIG. 10, unlike the first and second embodiments. The dome-shaped illumination device 45c is an example of irradiating light from the "obliquely upward direction" in the claims. Light from various angles from the irradiation unit 46c of the dome-shaped illumination device 45c and light from at least two directions from the vertical direction of the coaxial epi-illumination device 45a can be irradiated. Note that the same components as those in the first and second embodiments are denoted by the same reference numerals in the drawings and the description thereof is omitted.

[0057] Figure 11 is a cross-sectional view of the dome-shaped illumination device 45c as seen from above. In the dome-shaped illumination device 45c installed under the objective lens 43, an LED light source 62 is provided at the edge of the dome in FIG. 3. As shown in FIG. 10, the light irradiated from the LED light source 62 hits the reflector 61 inside the dome-shaped illumination device 45c. The reflected light is reflected by the semiconductor chip 48 and enters the imaging unit 40.

[0058] In the third embodiment, different from the second embodiment, light is reflected at all angles and irradiates the semiconductor chip 48. For this reason, the height of the dome-shaped illumination device 45c is configured not to need to be changed. Therefore, the dome-shaped illumination device 45c installed under the objective lens 43 has a fixed position. The hole 63b is a through hole on the upper side of the dome-shaped illumination device 45c. Also, the hole 63c is a through hole on the lower side of the dome-shaped illumination device 45c. As shown in FIG. 10, the upper hole 63b is made smaller than the hole 63c.

[0059] Note that other configurations of the third embodiment are the same as those of the first embodiment described above.

[0060] (Appearance inspection method of the third embodiment) Next, the appearance inspection method of the third embodiment will be described. The appearance inspection method of the third embodiment is for obtaining the rotation amount and positional deviation of the semiconductor chip 48 on the transfer substrate 49 from the image data, and selecting a semiconductor chip 48 that performs a process different from that of the semiconductor chip 48 within a threshold value without transferring it from the transfer substrate 49 to the wiring substrate in advance. The different process is a process of determining not to use the semiconductor chip 48.

[0061] In step 300 (see FIG. 12), the transfer substrate 49 is placed on the placement table 30 of the appearance inspection apparatus 300. In step 301, a threshold value, a light quantity, and an imaging method related to the rotation amount and positional deviation of the semiconductor chip 48 are input to the data input unit 52. In step 302, the irradiation unit 46c irradiates light onto the semiconductor chip 48. The imaging unit 40 images the semiconductor chip 48 by the light reflected from the semiconductor chip 48, and acquires the image data of the semiconductor chip 48. In step 303, the control unit 51 selects the address of the semiconductor chip 48. In step 304, the detection unit 54 extracts the semiconductor chip 48 at the address selected from the image data. In step 305, the detection unit 54 determines whether the image data of the semiconductor chip 48 is saturated. In step 306, when the image data of the semiconductor chip 48 is not saturated, the detection unit 54 confirms the rotation amount and positional deviation of the semiconductor chip 48 from the image data of the semiconductor chip 48. In step 307, when the rotation amount or positional deviation of the semiconductor chip 48 is equal to or greater than the set threshold value, in step 308, the data imparting unit 55 imparts a marker indicating that the semiconductor chip 48 is not transferred from the transfer substrate 49 to the wiring substrate and is not used, and the process proceeds to step 309. When the rotation amount or positional deviation of the semiconductor chip 48 is not equal to or greater than the set threshold value, the process proceeds to step 309 without imparting a marker indicating that the semiconductor chip 48 is not transferred from the transfer substrate 49 to the wiring substrate and is not used. In step 309, when there is an unselected address, the process returns to step 303, and the steps from step 303 to step 309 are repeated. In step 309, when there is no unselected address, the data transmission unit 56 transmits the data imparted to the address to the apparatus that transfers the semiconductor chip 48 from the transfer substrate 49 to the wiring substrate. Further, the substrate transfer unit 57 sends the transfer substrate 49 to the apparatus that transfers the semiconductor chip 48 from the transfer substrate 49 to the wiring substrate.

[0062] In step 305 above, when the image data of the semiconductor chip 48 at the selected address is saturated, in step 308, the data assigning unit 55 assigns a marker indicating that it is not transferred from the transfer substrate 49 to the wiring substrate and not used to the address of the semiconductor chip 48, and the process proceeds to step 309.

[0063] (Effect of the Third Embodiment) In the third embodiment, the following effects can be obtained.

[0064] In the third embodiment, similar to the first embodiment above, by irradiating the semiconductor chip 48 disposed on the transfer substrate 49 with light, image data of the semiconductor chip 48 is acquired. From the acquired image data of the semiconductor chip 48, it can be confirmed that at least one of the rotation amount and the position of the semiconductor chip 48 deviates beyond a threshold value, so that the semiconductor chip 48 is rotating or displaced from its original position. As a result, an appearance inspection method capable of determining whether to use the semiconductor chip 48 can be provided.

[0065] In the third embodiment, as described above, in the step of acquiring image data, light from at least two directions is irradiated onto the semiconductor chip 48, and image data is acquired based on the reflected light from the semiconductor chip 48. Thereby, even when there is a tilted semiconductor chip 48c on the transfer substrate 49, since the reflected light is incident on the imaging unit 40, it is possible to acquire image data in which the rotation amount and the displacement of the position can be confirmed.

[0066] Also, in the third embodiment, one of the two directions is the vertical direction, and the other of the two directions is the obliquely upward direction. Thereby, image data of a plurality of appropriately transferred semiconductor chips 48 can be acquired by the light from the vertical direction, so that it is possible to determine whether to use the semiconductor chip 48. Also, even when the upper surface of the semiconductor chip 48 is inclined obliquely with respect to the horizontal direction by the light from the obliquely upward direction, image data of the inclined semiconductor chip 48c can be acquired, so that it is possible to determine whether to use it.

[0067] Also, in the third embodiment, in the step of determining not to use the semiconductor chip 48, a predetermined amount of light is irradiated onto the semiconductor chip 48, and image data is acquired by the reflected light from the semiconductor chip 48. In the image data, if the reflected light from the tilted semiconductor chip 48c excessively enters the imaging unit 40 and the pixel value is saturated, it is determined not to use the semiconductor chip 48. As a result, when transferring the semiconductor chip 48 from the transfer substrate 49 to the wiring substrate, in advance, the semiconductor chip 48 with a low probability of correct wiring will not be transferred, so that the working efficiency of the step of transferring the semiconductor chip 48 to the wiring substrate can be improved.

[0068] Note that other effects of the third embodiment are the same as those of the above-described first embodiment.

[0069] (Modification example) It should be considered that the embodiments and examples disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is shown not by the descriptions of the above-described embodiments and examples, but by the claims, and further includes all changes (modification examples) within the meaning and scope equivalent to the claims.

[0070] For example, in the above embodiment, an example where different processes do not use the semiconductor chip 48 is shown, but the present invention is not limited to this. For example, different processes repair the semiconductor chip 48. Or different processes may transfer manually.

[0071] Also, in the above embodiment, an example where the detection unit 54 is included in the control unit 51 is shown, but the present invention is not limited to this. For example, the detection unit 54 may be provided separately from the control unit 51.

[0072] Also, in the above embodiment, an example regarding the semiconductor chip 48 on the transfer substrate 49 is shown, but the present invention is not limited to this. For example, the semiconductor chip 48 on the wiring substrate after transfer from the transfer substrate 49 may be checked.

[0073] Also, in the above-described embodiment, a marker was given to the semiconductor chip 48 that performs a process different from the semiconductor chip 48 within the threshold value. However, the present invention is not limited to this. The data transmission unit 56 and the substrate transfer unit 57 may be configured such that the data providing unit 55 gives a marker to the semiconductor chip 48 within the threshold value and sends it to the next process.

[0074] Also, in the above-described embodiment, the control unit 51 changes the relative height with respect to the semiconductor chip 48 of the ring-shaped illumination device 45b. However, the present invention is not limited to this. The ring-shaped illumination device 45b may be fixed, and the height of the substrate holding unit that holds the transfer substrate 49 may be changed.

[0075] Also, in the second and third embodiments of the above-described embodiment, the illumination intensity was not changed. However, the change in the illumination intensity in the first embodiment may be applied to the second and third embodiments.

Explanation of Reference Numerals

[0076] 40 Imaging unit 45 Illumination unit 45a Coaxial epi-illumination device 45b Ring-shaped illumination device 45c Dome-shaped illumination device 46a to 46c Irradiation unit 48, (48a to 48c) Semiconductor chip 49 Transfer substrate (substrate) 50 Bump electrode 51 Control unit 52 Data input unit 53 Storage unit 54 Detection unit 55 Data providing unit 56 Data transmission unit 57 Substrate transfer unit 58 Illumination elevator (relative elevation mechanism) 100, 200, 300 Appearance inspection device

Claims

1. A step of irradiating a semiconductor chip disposed on a substrate with light and acquiring image data from the reflected light from the semiconductor chip; A step of checking whether at least one of the position of the semiconductor chip and the amount of rotation of the semiconductor chip in the image data deviates beyond a threshold value, and if it deviates beyond the threshold value, making a determination to perform a process different from that of the semiconductor chip within the threshold value. An appearance inspection method for a semiconductor chip, including this step.

2. In the step of performing a process different from that of the semiconductor chip within the threshold value, the different process is a process of determining not to use the semiconductor chip. The appearance inspection method for a semiconductor chip according to Claim 1.

3. In the step of acquiring the image data, the semiconductor chip is irradiated with light while changing the illumination intensity, and a plurality of the image data are acquired from the reflected light from the semiconductor chip at the plurality of illumination intensities. The appearance inspection method for a semiconductor chip according to Claim 2.

4. In the step of acquiring the image data, the semiconductor chip is irradiated with light from at least two directions, and the image data are acquired from the reflected light from the semiconductor chip. The appearance inspection method for a semiconductor chip according to Claim 2 or 3.

5. One of the two directions is the vertical direction, and the other of the two directions is the obliquely upward direction. The appearance inspection method for a semiconductor chip according to Claim 4.

6. In the step of acquiring the image data, the relative height of the light irradiation portion from the obliquely upward direction with respect to the substrate is changed, and the semiconductor chip is irradiated with light at each of a plurality of height positions, and a plurality of the image data are acquired from the reflected light from the semiconductor chip at each of the plurality of height positions. The appearance inspection method for a semiconductor chip according to Claim 5.

7. In the step of determining to perform a process different from that of the semiconductor chip within the threshold value, the semiconductor chip is irradiated with a predetermined amount of light, and the image data are acquired from the reflected light from the semiconductor chip. In the image data, if the reflected light from the tilted semiconductor chip is incident on the imaging unit excessively, the semiconductor chip with saturated pixel values is determined to perform a process different from that of the semiconductor chip within the threshold value. The appearance inspection method for a semiconductor chip according to Claim 4.

8. An appearance inspection device that inspects the position of the semiconductor chip and the amount of rotation of the semiconductor chip disposed on the substrate, respectively. A substrate holding unit that holds the substrate on which the semiconductor chip is disposed. An irradiation unit that irradiates light onto the semiconductor chip of the substrate held by the substrate holding unit. An imaging unit that images the semiconductor chip to be inspected. A control unit that determines whether at least one of the position of the semiconductor chip to be inspected and the amount of rotation of the semiconductor chip imaged by the imaging unit deviates beyond a threshold value, and when it deviates beyond the threshold value, performs control to determine that a process different from that of the semiconductor chip within the threshold value is to be performed on the semiconductor chip on the substrate. An appearance inspection device comprising:

9. The irradiation unit irradiates the semiconductor chip with light from at least two directions, a vertical direction and an obliquely upward direction. The apparatus further includes a relative lifting mechanism that changes the relative height between the substrate holding unit and the irradiation unit. The control unit is configured to perform control to change the height of the relative lifting mechanism when detecting a semiconductor chip in which a pixel value is saturated by reflected light from the semiconductor chip. The appearance inspection device according to claim 8.

10. The control unit is configured to perform control to determine that a process different from that of the semiconductor chip within the threshold value is to be performed on the semiconductor chip on the substrate when detecting a semiconductor chip in which a pixel value is saturated by reflected light from the semiconductor chip. The appearance inspection device according to claim 8.

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