[0062] (First embodiment)
[0063]
[0064] First, refer to figure 1 with figure 2 The structure of the X-ray inspection apparatus of this embodiment will be described. figure 1 Is a cross-sectional view schematically showing the X-ray inspection apparatus 1 of this embodiment, figure 2 It is a block diagram showing the structure and functions of the X-ray inspection apparatus 1. Such as figure 1 with figure 2 As shown, the X-ray inspection apparatus 1 has a carry-in preparation unit 10, an imaging unit 20, and a carry-out preparation unit 30.
[0065] In addition, figure 1 It is a diagram schematically showing the flow of the substrate during inspection. Refer to image 3 The X-ray shielding device will be described.
[0066] Such as figure 1 As shown, the main body of the X-ray inspection apparatus 1 is provided with an imaging unit 20 for X-ray imaging, and on the upstream side (the left side of the figure) of the imaging unit 20, a loading preparation unit for loading the substrate K of the inspection target is provided. 10. In addition, a carry-out preparation unit 30 for carrying out the substrate is provided on the downstream side (the right side of the figure) of the imaging unit 20. The conveyance mechanism 111 for conveying the board|substrate from an upstream process (for example, a reflow process) is arrange|positioned in the carrying-in preparation part 10. The transport mechanism 111 is capable of moving in the vertical direction in the figure, and is connected to the transport mechanism 203 arranged in the imaging unit 20. The substrate K transported from the upstream process is transported into the imaging unit 20 via the carry-in preparation unit 10 (transporting mechanism 111), and after necessary imaging and inspection are performed, it is delivered to the transport mechanism 311 of the carry-out preparation unit 30. The conveying mechanism 311 can move in the up-down direction in the figure, and conveys to the downstream process from the export outlet. In this way, the X-ray inspection apparatus 1 of the present embodiment assumes that the substrate is automatically inspected in the middle of the production line (assembly line).
[0067] First, the carry-in preparation unit 10 will be described.
[0068] The carry-in preparation unit 10 includes an carry-in port for carrying in a substrate K as an inspection target, and a box-shaped member (hereinafter referred to as carry-in preparation room 100) having an export port for sending the substrate to the imaging unit. The member is made of a material that shields X-rays.
[0069] In addition, in the following description, the box-shaped member through which the substrate to be inspected passes is referred to as the carry-in preparation room 100, and the mechanism located in the carry-in preparation room 100 and the device that controls the mechanism are collectively referred to as the carry-in preparation unit 10. In addition to the carry-in preparation room 100, the carry-in preparation unit 10 further includes a transport mechanism 111, an elevating mechanism 112, and a control unit 120.
[0070] The transport mechanism 111 is a device for moving the placed object in the transport direction (X-axis direction in the figure). The transport mechanism 111 is typically composed of a linear actuator, a guide rail, a transmission belt, etc., but other devices may also be used. The substrate K transported from the upstream process is transported into the transport preparation room 100 by the transport mechanism 111.
[0071] In addition, the transport mechanism 111 is a structure that can be moved in a direction (the Z-axis direction in the figure) orthogonal to the transport direction of the substrate by the elevator mechanism 112. In addition, the elevating mechanism 112 only needs to be able to move the transport mechanism 111, and it may be driven by a linear actuator or the like, or it may be driven by obtaining power through a belt or a chain.
[0072] When the substrate K carried in the carrying-in preparation room 100 reaches the export exit, the transport mechanism 111 sends the substrate K to the imaging room 200 for imaging and inspection.
[0073] The control unit 120 is a device that controls the operations of the transport mechanism 111 and the elevating mechanism 112. The control unit 120 may be realized by running software on a general-purpose computer, for example, or may be realized by dedicated hardware. The specific control content performed by the control unit 120 will be described later.
[0074] Next, the imaging unit 20 will be described.
[0075] The imaging unit 20 is provided with an import port for carrying in the substrate K to be inspected from the carry-in preparation room 100; and a box-shaped member (hereinafter referred to as the imaging chamber 200) having an export port for sending the substrate to the carry-out preparation room 300 . The member is made of a material that shields X-rays.
[0076] In addition, in the following description, the box-shaped member that is the area where the substrate is inspected is referred to as the imaging room 200, and the mechanism located in the imaging room 200 and the device that controls the mechanism are collectively referred to as the imaging unit 20. In addition to the imaging room 200, the imaging unit 20 has an X-ray generator 201, an X-ray detector 202, a transport mechanism 203, a control unit 204, and an inspection unit 205.
[0077] The X-ray generator 201 is a device that emits X-rays. Here, in order to perform X-ray CT imaging, an X-ray source that emits an X-ray beam diffused into a cone-shaped cone beam is used.
[0078] The X-ray detector 202 is a two-dimensional X-ray detector that detects X-rays emitted from an X-ray source and transmitted through a substrate to be inspected. As the X-ray detector 202, an I.I. (Image Intensifier) tube or FPD (Flat panel detector) can be used. In addition, one X-ray detector is used here, but multiple X-ray detectors can also be used.
[0079] In addition, the X-ray generator 201 and the X-ray detector 202 are configured to be movable in three-dimensional directions by a stage (not shown).
[0080] Since the conveying mechanism 203 is the same as the conveying mechanism 111 mentioned above, description is abbreviate|omitted.
[0081] The control unit 204 is a device that controls the X-ray imaging of the inspection target by controlling the operations of the X-ray generator 201, the X-ray detector 202, and the transport mechanism 203.
[0082] Specifically, the control unit 204 controls the reception of the substrates carried in from the carry-in preparation room 100, the discharge of the substrates after the inspection is completed, the positioning of the X-ray generator 201 and the X-ray detector 202 using a stage not shown, and the X-ray X-ray radiation by the generator 201, etc.
[0083] The inspection unit 205 is an apparatus that performs substrate inspection based on the X-ray image detected by the X-ray detector 202. In this embodiment, by changing the relative positions between the X-ray generator and X-ray detector and the inspection target, multiple times (several to tens of times) imaging is performed to obtain X-ray transmission at various angles. Through the image, the three-dimensional data of the substrate is reconstructed based on these data. This is an imaging method called oblique X-ray CT, which is suitable for inspection of objects with no thickness such as electronic substrates. In addition, the specific calculation method of the oblique X-ray CT is well-known, and the description is omitted.
[0084] The inspection unit 205 inspects the substrate based on the acquired three-dimensional data. For example, it determines the position of the components on the substrate, the state of soldering (wetting height, angle, etc.), and generates a result. The generated result may be sent to a downstream process, or may be provided to the user of the device via a display device not shown.
[0085] The control unit 204 and the inspection unit 205 can use, for example, a general-purpose arithmetic device called a CPU (Central Processing Unit). The control unit 204 and the inspection unit 205 can be equipped with RAM (Random Access Memory) and other memories, as well as ROM (Read Only Memory), HDD (Hard Disk Drive), and SDD (Solid State Drives). : Solid State Drive) etc. In addition, any input device such as a keyboard, buttons, switches, and pointing devices that the user can input instructions may be provided. In addition, it is also possible to provide any output device such as a display screen, a speaker, etc., which presents the test result to the user through video, sound, and the like. That is, it is possible to realize these functional parts by using an ordinary computer system.
[0086] In addition, in the present embodiment, the imaging unit 20 performs the inspection of the substrate based on the X-ray transmission image, but it may have other inspection devices. For example, it can also be equipped with a camera that acquires a visible light image, and inspect the substrate based on the visible light image.
[0087] Next, the unloading preparation unit 30 will be described.
[0088] The carry-out preparation unit 30 includes an carry-in port for carrying in the inspected substrate K from the imaging room 200, and a box-shaped member (hereinafter referred to as the carry-out preparation chamber 300) having an export port for sending the substrate to a downstream process. The member is made of a material that shields X-rays.
[0089] In addition, in the following description, the box-shaped member through which the substrate to be inspected passes is referred to as the unloading preparation chamber 300, and the mechanism located in the unloading preparation chamber 300 and the device that controls the mechanism are collectively called the unloading preparation unit 30. The unloading preparation unit 30 includes a transport mechanism 311, an elevating mechanism 312, and a control unit 320 in addition to the loading preparation room 300.
[0090] After the inspection, the substrate K sent from the imaging room 200 is moved to the unloading preparation room 300 by the transport mechanism 311. The conveying mechanism 311 and the elevating mechanism 312 included in the unloading preparation section 30 are the same as the conveying mechanism 111 and the elevating mechanism 112, so detailed descriptions are omitted. The carry-out preparation room 300 also has the same carry-in and carry-out ports as the carry-in preparation room 100, and carries the substrate K into the downstream process.
[0091]
[0092] Next, refer to image 3 The mechanism for preventing X-ray leakage to the outside of the loading preparation room 100 and the removal preparation room 300 will be described. image 3 It is a cross-sectional view showing the structure of the carry-in preparation room 100 and the carry-out preparation room 300 in more detail.
[0093] The shielding plates 113A and 113B are plate-shaped members arranged on the XY plane so as to sandwich the transport mechanism 111. The shielding plates 113A and 113B may be ordinary members that shield radiation, and typically include lead, tungsten, and the like.
[0094] In addition, the peripheries of the shielding plates 113A and 113B are in contact with the inner wall of the carry-in preparation room 100 to form a structure to shield radiation. In addition, the transport mechanism 111, the shielding plate 113A, and the shielding plate 113B are formed in a structure that can be moved integrally. In this embodiment, these are collectively referred to as a mobile device 110.
[0095] In addition, since each member included in the unloading preparation room 300 differs only in the hundredth place of the reference numeral, the content is the same, and therefore the description of each member is omitted.
[0096] Figure 4 It is a diagram explaining the movable range of the mobile device 110. From Figure 4 It can be seen that the movable range of the moving device 110 in the Z-axis direction is the upper limit of the state where the conveying mechanism 111 is located at the height of the carry-in port, and the lower limit of the state where the conveying mechanism 111 is located at the height of the carry-out port. That is, it is formed in a state in which either (or both) of the shield plate 113A and the shield plate 113B must be present between the import port and the export port. Since the export port of the carry-in preparation room 100 is connected to the imaging room 200, there is a possibility that X-rays may invade from the export port, but the intruded X-rays are shielded by the shielding plate and do not reach the import port. That is, the imaging room 200 can be spatially separated from the outside of the apparatus. In addition, the separated state is maintained regardless of the position of the mobile device 110.
[0097] In addition, in order to obtain the above-mentioned effects, it is necessary to make the interval d1 between the shielding plates 113A and 113B smaller than the shortest distance d2 between the import port and the export port.
[0098] In addition, although the carrying-in preparation room 100 is used as an example, the structure is the same when the substrate is carried out from the imaging room 200 via the carrying-out preparation room 300.
[0099]
[0100] Next, refer to Figure 5-7 , Describe the control of board loading, inspection, and removal.
[0101] Figure 5 It is a flowchart showing the control flow of board loading. Figure 5 The processing shown is executed by the control unit 120 included in the carry-in preparation unit 10.
[0102] In addition, in this example, each of the carry-in preparation unit 10, the imaging unit 20, and the carry-out preparation unit 30 maintains their states, and determines whether they can be transported while referring to the mutual states. There are three statuses: "waiting to move in", "working" and "waiting to move out".
[0103] First, in step S11, the moving device 110 is moved to the upper part using the lifting mechanism 112, and thereafter, the state is changed to "waiting for loading". Thereby, the conveyance mechanism 111 is connected with the conveyance path of an upstream process.
[0104] Next, in step S12, it is determined whether or not the preparation of the upstream process is completed. In this step, it is confirmed whether or not the preparation for loading into the inspection device is completed for the equipment located in the upstream process. Here, when the determination is affirmative, the process proceeds to step S13, the conveying mechanism 111 is driven, and the substrate to be inspected is received. In the case of a negative determination, it waits for a fixed time and repeats the determination.
[0105] When the board to be inspected is carried in from the carry-in port, in step S14, the status is changed to "in operation". Then, in step S15, the moving device 110 is moved to the lower part, and the state is changed to "waiting for unloading". Thus, the conveying mechanism 111 and the conveying mechanism 203 are connected.
[0106] Next, in step S16, it is determined whether the preparation of the shooting room 200 is finished. In this step, the control unit 204 included in the imaging unit 20 determines whether the reception preparation is completed. In this step, when the state of the imaging unit 20 is "waiting for carry-in", it becomes a positive judgment, and when it is "working" and "waiting for carry-out", it becomes a negative judgment. Here, when the determination is affirmative, the process proceeds to step S17, the transport mechanism 111 is driven, and the substrate to be inspected is sent out. In the case of a negative determination, it waits for a fixed time and repeats the determination.
[0107] When the inspection target board is finished being carried into the imaging room 200, the status is changed to "in operation" in step S18. After that, the process proceeds to step S11 to move the mobile device to the initial position (upper part).
[0108] Image 6 It is a flowchart showing the control flow of the board inspection. Image 6 The shown processing is executed by the control unit 204 included in the imaging unit 20.
[0109] First, in step S21, the status is changed to "waiting for import".
[0110] Next, in step S22, it is determined whether the preparation for carrying in the substrate from the carrying-in preparation chamber 100 is completed. In this step, when the status of the carry-in preparation unit 10 is “waiting for carry-out”, it becomes a positive judgment, and when it is “working” and “waiting for carry-in”, it becomes a negative judgment. Here, when the determination is affirmative, the process proceeds to step S23, the transport mechanism 203 is driven, and the substrate to be inspected is received. In the case of a negative determination, it waits for a fixed time and repeats the determination.
[0111] When the board to be inspected is loaded in, in step S24, the status is changed to "in operation". Also, a check is performed in step S24. That is, X-ray irradiation and imaging are performed, the obtained image is sent to the inspection unit 205, and the inspection is performed. When the inspection is completed, in step S25, the status is changed to "waiting to move out".
[0112] In addition, in this example, the process proceeds to step S25 after the completion of the inspection, but it is also possible to perform shooting and inspection in parallel. That is, when the X-ray imaging is finished and the inspection is started by the inspection unit 205, the substrate may be discharged immediately.
[0113] Next, in step S26, it is determined whether or not the reception preparation of the unloading preparation unit 30 is completed. In this step, when the status of the unloading preparation unit 30 is "waiting for import", it becomes a positive determination, and when it is "in operation" and "waiting for unloading", it becomes a negative determination. Here, when the determination is affirmative, the process proceeds to step S27, the conveying mechanism 203 is driven, and the inspection-finished substrate is carried out. In the case of a negative determination, it waits for a fixed time and repeats the determination.
[0114] Figure 7 It is a flowchart showing the control flow of the board out. Figure 7 The illustrated processing is executed by the control unit 320 included in the unloading preparation unit 30.
[0115] First, in step S31, the moving device 310 is moved to the lower part by the lifting mechanism 312, and thereafter, the state is changed to "waiting for loading". Thus, the conveying mechanism 311 and the conveying mechanism 203 are connected.
[0116] Next, in step S32, it is determined whether the preparation for carrying in the substrate from the imaging room 200 is completed. In this step, when the state of the imaging unit 20 is "waiting for unloading", it becomes a positive determination, and when it is "working" and "waiting for unloading", it becomes a negative determination. Here, when the determination is affirmative, the process proceeds to step S33, the conveying mechanism 311 is driven, and the substrate whose inspection has been completed is received. In the case of a negative determination, it waits for a fixed time and repeats the determination.
[0117] When the board that has been inspected is loaded in from the import port, the status is changed to "in operation" in step S34. Then, in step S35, the moving device 310 is moved to the upper part, and the state is changed to "waiting for unloading".
[0118] Next, in step S36, it is determined whether or not the preparation of the downstream process is completed. In this step, for the equipment located in the downstream process, it is confirmed whether the import preparation from the inspection device is completed. Here, when the determination is affirmative, the process proceeds to step S37, the conveying mechanism 311 is driven, and the inspection-finished substrate is carried out. In the case of a negative determination, it waits for a fixed time and repeats the determination.
[0119] When the unloading of the board is completed, in step S38, the status is changed to "in operation". After that, proceed to step S31 to move the mobile device to the initial position (lower part).
[0120] As described above, the inspection device of this embodiment shields X-rays generated in the imaging room by the shielding member provided in the mobile device. According to this structure, a mechanism for independently opening and closing the X-ray shielding member is not required, and the cost of the device can be suppressed. In addition, even when X-ray irradiation is performed in the imaging room, it is possible to carry in and out operations, and therefore it is easy to achieve high-speed inspection. In addition, the carry-in preparation part and the carry-out preparation part operate independently, so that the next substrate can be carried into the inspection room before the substrate after the inspection is completely carried out from the inspection device. That is, the interval of X-ray imaging can be shortened, and therefore the overall inspection time can be shortened.
