JP3954602B2 - Automatic pattern inspection system - Google Patents

Description

  The present invention relates to an automatic pattern inspection apparatus that sequentially images a circuit pattern formed on a film carrier with an imaging camera and automatically inspects a defect in the circuit pattern.

This type of automatic inspection of circuit pattern defects (for example, thickening, disconnection, shorting, thinning, etc.) formed on film carrier tape (hereinafter referred to as TAB tape: Tape Automated Bonding) for mounting electronic components Various automatic inspection apparatuses have been proposed in the past (for example, see Patent Documents 1 to 5).
JP 2001-174229 A JP-A-7-280863 JP 2001-160570 A JP-A-6-34332 JP-A-6-138177

  The automatic inspection apparatus described in Patent Document 1 sequentially inspects and inspects a circuit pattern formed on a TAB tape with two imaging cameras.

  In the electronic component inspection apparatus described in Patent Document 2, the open inspection means and the short inspection means are arranged apart from each other in the transport direction of the TAB tape, and the circuit pattern formed on the TAB tape by these inspection means. Inspects for disconnection and short circuit.

  The inspection apparatus for film carriers described in Patent Document 3 automatically inspects the circuit pattern formed on the TAB tape by a defective pattern inspection apparatus (CCD camera), such as electrical disconnection and short circuit, and is defective. The (NG) pattern is subjected to defective marking by a marking device.

  The precision part appearance inspection apparatus described in Patent Document 4 uses a flash light source that emits a flash with a very short light emission time width and a solid-state image sensor camera to inspect circuit patterns for disconnection, short circuit, bending, lack, etc. It is. In this document, when a flash light source with a light emission time width of about 4 to 7 μms is used, a faster shutter speed (14 to 25 times) can be obtained compared to a normal mechanical shutter, so there is no need to stop the camera. It is described that a circuit pattern can be continuously imaged while being moved.

  The semiconductor inspection apparatus described in Patent Document 5 includes a plurality of tape movable stages that move and advance and retract a TAB tape on which a device to be measured is mounted at predetermined intervals, and a TAB when each tape movable stage advances. A plurality of probe contact units each including a plurality of probes that are in electrical contact with each object to be measured on the tape; and a contact block that moves these probe contact units to a position facing the tape movable stage. The tape movable stage is advanced to press the TAB tape against a plurality of probe contact units, and a plurality of objects to be measured are electrically inspected simultaneously by the probes of each probe contact unit.

  In the conventional automatic pattern inspection apparatus described in Patent Documents 1 to 4, since the TAB tape transport direction is substantially horizontal, an imaging camera is added in parallel to the tape transport direction in order to reduce the inspection time. As a result, there is a problem that the conveying path becomes longer and the apparatus becomes larger. In addition, when the number of imaging cameras is increased, tension is applied to the TAB tape with a long span. In particular, it becomes difficult to apply a large tension to the TAB tape made of a thin film, and the inspection target tape is restricted. Arise. Further, when the span becomes long, there also arises a problem that the TAB tape meanders in the width direction during conveyance.

In the semiconductor inspection apparatus described in Patent Document 5, four probe contact units are arranged in a horizontal plane, four on each side of the contact block, so that the shape of the apparatus itself in plan view becomes large. There was a problem of requiring a large installation space. Further, since the TAB tape is zigzag meandering before and after each probe contact unit in order to reduce the size of the apparatus, the travel of the TAB tape is complicated, and the number of tension rollers for applying tension to the tape increases. There was a problem that the assembly of the apparatus, the adjustment work, and the TAB tape mounting work were troublesome.
Furthermore, since each tape movable stage is moved forward together with the TAB tape and the circuit pattern as the object to be measured is brought into contact with the probe, there is also a problem that it is difficult to make the tension of the TAB tape constant in each stage.

  The present invention has been made to solve the above-described conventional problems. The object of the present invention is to reduce the horizontal length of the conveyance path and to install two or more imaging cameras. However, the tension mechanism is simple, and it is not necessary to apply tension to the film carrier tape over a long span, and the tape length between the camera in the descending conveyance area and the ascending conveyance area can be adjusted according to the pitch of the circuit pattern. An object of the present invention is to provide an automatic pattern inspection apparatus.

  In order to achieve the above object, a first invention includes an inspection unit having a conveyance path bent in a substantially U shape, a conveyance unit that conveys an electronic component mounting tape along the conveyance path, and the inspection unit. A plurality of imaging cameras for imaging a circuit pattern formed on the tape, wherein the imaging cameras are spaced apart from each other in the transport direction of the tape with respect to the descending transport area and the ascending transport area of the transport path. At least two at a time, and the conveying means is arranged at the turn-up portion of the conveying path so that the height can be adjusted, and the ascending conveying area from the imaging camera in the descending conveying area corresponding to the pitch of the circuit pattern. A pitch adjusting roller for adjusting the tape length to the imaging camera is provided.

  According to a second aspect of the present invention, meandering detecting means for detecting meandering in the width direction of the tape, and means for moving and adjusting the pitch adjusting roller in a direction opposite to the meandering direction of the tape based on a detection signal from the meandering detecting means. Are provided.

  According to a third aspect of the present invention, the imaging camera is arranged so that the optical axis of the camera is parallel to the surface of the tape, the light from the light source is guided to the tape, and the reflected light from the tape is reflected to the imaging camera. It is equipped with a mirror.

  In the present invention, since the descending conveyance area and the ascending conveyance area of the conveyance path bent in a U-shape are used as the installation locations of the imaging camera, the horizontal length of the conveyance path can be shortened and the apparatus can be downsized. To do. In addition, since two or more cameras are installed in each transfer area, the inspection time can be shortened.

When the tape meandering in the width direction of the tape is detected, the meandering in the width direction of the tape can be corrected by moving and adjusting the pitch adjusting roller in the direction opposite to the meandering direction. Therefore, even when the span is long, the tape can be transported in a stable state.
By adjusting the height with the pitch adjustment roller, the tape length from the imaging camera in the descending conveyance area to the imaging camera in the ascending conveyance area can be adjusted, so that various circuit patterns with different pitches can be inspected. it can.

  Since the imaging camera is arranged so that the optical axis of the camera is parallel to the surface of the tape, the size of the apparatus in the direction orthogonal to the tape surface can be shortened, and further miniaturization is possible.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.
FIG. 1 is a schematic configuration diagram inside the apparatus showing an embodiment of an automatic pattern inspection apparatus according to the present invention, FIG. 2 is a perspective view showing an adjustment mechanism of a pitch adjusting roller, FIG. 3 is a schematic perspective view of an inspection section, 4 is a diagram showing the positional relationship and interval of the imaging camera, FIG. 5 is a diagram showing a circuit pattern, FIGS. 6A to 6F are diagrams for explaining imaging of the circuit pattern by the imaging camera, and FIG. It is a flowchart of a pattern inspection. The present embodiment shows an example in which the present invention is applied to an automatic pattern inspection apparatus that automatically inspects a defect of a circuit pattern formed on a TAB tape and applies NG marking to an NG pattern.

  In FIG. 1 to FIG. 6, an automatic pattern inspection apparatus generally indicated by reference numeral 1 includes an apparatus main body 3 installed on a floor surface 2. The width of the TAB tape 4 that can be inspected by the automatic pattern inspection apparatus 1 is about 35 to 160 mm, and the tape thickness is about 30 to 125 μm. The inspection items of the circuit pattern 5 are thickening, disconnection, shorting, thinning, pitch shift, protrusion, chipping, lead bending, pinhole, inter-conductor ratio, minimum pattern width, minimum gap width, and the like.

  The apparatus main body 3 is formed in a box shape that is long in the left-right direction, and the inside thereof has six sections along the transport direction of the TAB tape 4, that is, an unwinding runner part A, an inspection part B, a buffer part C, and a verification part. D, NG marking part E and winding runner part F. A control unit (not shown) for computer-controlling the entire apparatus is incorporated in the apparatus main body 3.

  The TAB tape 4 is made of a translucent film made of polyimide, and a large number of fine circuit patterns 5 having the same shape are formed on the surface side in the longitudinal direction at a predetermined pitch. The circuit pattern 5 may be formed in a single row, but a plurality of rows (4 rows in FIG. 3 and 3 rows in FIG. 5) may also be formed in the width direction of the TAB tape 4. Such a circuit pattern 5 is formed by adhering a copper foil to the surface of the tape with an adhesive and etching it. The circuit pattern 5 has a thickness of 10 to 30 μm and a width of about 10 to 50 μm at the inner lead wire portion to be bonded. Perforations 6 (only the perforations 6 on both sides are shown in FIG. 3) are formed between the left and right sides of the TAB tape 4 and between the circuit patterns 5 and 5 adjacent in the width direction.

  The unwinding runner part A is provided with an unwinding device 10 for supplying the TAB tape 4 to the inspection part B. The unwinding device 10 includes an unwinding reel 11 on which the TAB tape 4 is wound with its surface (circuit pattern forming surface) facing upward, and a slack portion 4A of the TAB tape 4 unwound from the unwinding reel 11. Are provided with a slack detection sensor 12 for detecting the amount of slack, and a plurality of feed rollers 13a to 13c. The slack portion 4A of the TAB tape 4 is a tape portion slacked in a U shape between the two feed rollers 13a and 13b. The TAB tape 4 is conveyed in a state where the front and back surfaces are parallel to the front-rear direction of the apparatus from the start to the end of conveyance.

  The slack detecting sensor 12 includes four photoelectric sensors 13a to 13d and reflectors arranged at predetermined intervals in the height direction so as to face the opposite sides of the slack portion 4A of the TAB tape 4, respectively. 14a-14d. When the lower end of the slack portion 4A is detected by the slack detection sensor 12, the detection signal is sent to the control portion. The control unit drives a tape driving motor (not shown) based on a detection signal from the slack detection sensor 12, and the bottom end of the slack portion 4A is always the lowermost light sensor 13a and the uppermost photoelectric sensor 13d. The TAB tape 4 is unwound so as to be positioned between them.

  The inspection section B is a section that automatically images the circuit pattern 5 formed on the TAB tape 4, and transports the TAB tape 4 along the transport path 21 of the TAB tape 4 and the transport path 21. Conveying means 22, a pattern imaging device 23 that automatically images the circuit pattern 5 of the TAB tape 4, a table device 51 that moves and adjusts the pattern imaging device 23 in the X-axis, Y-axis, and Z-axis directions, and a TAB tape The first and second warp correction mechanisms 52A, 52B and the like for correcting the warp in the tape width direction 4 are provided.

  The conveyance path 21 is formed in a conveyance path bent in a substantially U shape when viewed from the front, so that a lower conveyance area 21A for conveying the TAB tape 4 vertically downward and an ascending conveyance area 21B for conveying the TAB tape 4 upward. And a folded portion 21C that forms a connecting portion between the descending conveyance area 21A and the ascending conveyance area 21B and folds the TAB tape 4 upward.

  The conveying means 22 is disposed in the tension sprocket 25 disposed at the uppermost position of the descending conveying area 21A, the drive sprocket 26 disposed at the uppermost position of the ascending conveying area 21B, and the folding portion 21C. The pitch adjusting roller 27 and the tape driving motor are used. Here, the descending conveyance area 21 </ b> A is a substantially vertical conveyance path portion between the tension sprocket 25 and the pitch adjusting roller 27. The ascending conveyance area 21 </ b> B is a substantially vertical conveyance path portion between the pitch adjusting roller 27 and the drive sprocket 26.

  The tension sprocket 25 has a built-in torque motor, which gives a predetermined tension to the TAB tape 4 by applying a torque in the direction opposite to the transport direction of the TAB tape 4 (the direction of arrow 28 in FIG. 1). Has been granted.

  The drive sprocket 26 is configured to be intermittently driven in the tape transport direction by a drive motor (not shown).

  The pitch adjusting roller 27 is provided so as to be movable and adjustable in the vertical direction (Z direction) and the front and rear direction (Y direction) by the adjusting mechanism 30 shown in FIG. The adjusting mechanism 30 includes a bearing member 32 that holds the shaft 31 of the pitch adjusting roller 27, a Z-direction driving motor 34 that moves the bearing member 32 in the vertical and front-rear directions, a Y-direction driving motor 35, and the like. ing. The pitch adjusting roller 27 is rotatably attached to the tip end portion of the shaft 31, and the TAB tape 4 is attached to the lower surface side over a substantially half circumference.

  The Z-direction drive motor 34 is attached downward on the upper surface of a case 36 that is long in the vertical direction, and a screw rod 37 is attached to its output shaft. The screw rod 37 is accommodated in the case 36, and a nut 38 protruding from one side surface of the bearing member 32 is screwed. The nut 38 is inserted into the case 36 so as to be prevented from rotating and movable up and down. Therefore, by rotating the screw rod 37 by driving the Z-direction drive motor 34, the nut 38 and the bearing member 32 are raised or lowered along the screw rod 37, thereby adjusting the height of the pitch adjusting roller 27. Is done. The height adjustment range of the pitch adjusting roller 27 is about 150 mm at the maximum.

  The Y-direction drive motor 35 is horizontally attached to the rear surface of the case 39 that is long in the front-rear direction, and a screw rod 40 is attached to the output shaft thereof. The case 39 is fixed to the apparatus main body side. The screw rod 40 is accommodated in the case 39, and a nut 41 protruding from one side surface of the case 36 is screwed. The nut 41 is inserted into the case 39 so as not to rotate but to be movable back and forth. Therefore, by rotating the screw rod 40 by driving the Y-direction drive motor 35, the nut 41 moves forward or backward along the screw rod 40, so that the case and the bearing member 32 also move forward or backward together with the nut 41. Thus, the position of the pitch adjusting roller 27 in the front-rear direction is adjusted. The pitch adjusting roller 27 and the Y-direction driving motor 35 constitute a means for correcting the meandering of the TAB tape 4 in the width direction.

  The pattern imaging device 23 includes a total of four imaging cameras 55A to 55D, each of which is provided in each of the descending conveyance area 21A and the ascending conveyance area 21B of the conveyance path 21 in order to shorten the inspection time. Has been. These imaging cameras 55A to 55D are CCD cameras, and are arranged at predetermined intervals in the vertical direction of the descending conveyance area 21A. These imaging cameras 55A to 55D are arranged so that the optical axis of the camera is horizontal and parallel to the surface on which the circuit pattern 5 of the TAB tape 4 is formed. In addition, each of the imaging devices 55A to 55 includes a light source 56, a reflection mirror 57, an omnidirectional illumination device 58, an optical fiber 59, and the like as attached optical components attached externally.

  The light source 56 is disposed above the inspection unit B, and light is picked up by the optical fiber 59 when the circuit pattern 5 is captured by the imaging cameras 55A to 55D. The omnidirectional illumination devices 58 of the imaging cameras 55A to 55D are used. Led to.

  The omnidirectional illumination device 58 forms a hemispherical diffusion surface on the inner surface, and is disposed close to the surface of the TAB tape 4 as shown in FIG. The light from the light source 56 guided from the optical fiber 59 to the omnidirectional illumination device 58 is reflected and diffused by the diffusing surface to be diffused indirect light and irradiate the pattern 5 of the TAB tape 4. Then, the diffusely reflected light is reflected by the TAB tape 4 and then returns to the omnidirectional illumination device 58 again. From the slit formed at a position decentered from the center of the diffusion surface, the diffuse reflection light is external to the omnidirectional illumination device 58. Is reflected by the reflection mirror 57 and guided to the imaging cameras 55A to 55D, and the circuit pattern 5 is imaged by being received by the light receiving element (CCD). Note that such an omnidirectional illumination device 58 has been conventionally known as disclosed in, for example, Patent Document 1 described above, and a detailed description of the detailed structure thereof will be omitted.

  The reflection mirror 57 is disposed behind each of the imaging cameras 55A to 55D so as to be inclined at approximately 45 ° with respect to the optical axis of the camera.

  The table device 51 on which the pattern imaging device 23 is mounted includes a Y-axis table 62 disposed on a fixed base 61, and first and second table mechanisms disposed on the Y-axis table 62. 51A and 51B. The fixed base 61 is positioned below the conveyance path 21 and is fixed to the apparatus main body side. The Y-axis table 62 is disposed above the fixed base 61 so as to cross the descending conveyance area 21A and the ascending conveyance area 21B, and constitutes a common part of the first and second table mechanisms 51A, 51B. The Y-axis table 62 is disposed on the fixed base 61 so as to be movable in the front-rear direction along a linear guide (not shown). When the circuit pattern 5 is imaged by the pattern imaging device 23, a Y-axis motor is provided. 64 is configured to reciprocate in the front-rear direction. A screw rod 65 is attached to the output shaft of the Y-axis motor 64, and a nut 66 provided at the center of the lower surface of the Y-axis table 62 is screwed to the screw rod 65. A concave portion 68 is formed at the center of the front end surface of the Y-axis table 62 to enable the travel of the TAB tape 4 and movement adjustment of the pitch adjusting roller 27 in the vertical and front-rear directions. First and second table mechanisms 51A and 51B are installed.

  The first table mechanism 51A performs height adjustment, focal length adjustment, and the like of the two imaging cameras 55A and 55B disposed in the descending conveyance area 21A, and controls these imaging cameras 55A and 55B during imaging. It is moved along the circuit pattern 5, and is provided with a Z block 71 </ b> A installed so as to be located behind the descending conveyance area 21 </ b> A at the upper left end portion of the Y-axis table 62.

  In front of the Z block 71A, first and second S-axis tables 72A and 72B are arranged apart in the vertical direction. The upper first S-axis table 72A is moved and adjusted in the vertical direction by the Z-axis motor 73. The Z-axis motor 73 is fixed downward on the block 71A, and a nut 75 protruding from the back surface of the first S-axis table 72A is screwed onto a screw rod 74 provided on the output shaft. .

  In the first S-axis table 72A, an X-axis motor 80 for moving and adjusting the first camera mounting member 79 in the left-right direction (X direction) and a second S-axis table 72B are moved in the vertical direction. An S-axis motor 85 for adjustment is attached. The X-axis motor 80 is mounted horizontally on the left end of the first S-axis table 72A, and a nut 83 protruding from the back surface of the first camera mounting member 79 is provided on a screw rod 82 provided on the output shaft. It is screwed. On the first camera mounting member 79, an upper imaging camera 55A, its reflecting mirror 57, and an omnidirectional illumination device 58 are mounted.

  The second S-axis table 72B is disposed below the first S-axis table 72A, and is configured to be adjusted in height by the S-axis motor 85. The S-axis motor 85 is mounted downward on the back side of the first S-axis table 72A, and a nut 87 protruding from the back surface of the second S-axis table 72B on the screw rod 86 provided on the output shaft. Are screwed together. A second camera mounting member 88 is fixed to the front surface side of the second S-axis table 72B. The second camera mounting member 88 is connected to the first camera mounting member 79 through a linear guide 90 so as to be movable up and down, and the imaging camera 55B, its reflection mirror 57 and all directions are arranged on the front side. A mold lighting device 58 is attached.

  The height adjustment of the imaging camera 55 </ b> A is performed by driving the Z-axis motor 73. That is, when the screw rod 74 is rotated by driving the Z-axis motor 73, the nut 75 moves up and down along the screw rod 74, so that the first S-axis table 72A and the first camera mounting member 79 also move up and down. Then, the height of the imaging camera 55A is adjusted. At this time, the second S-axis table 72B and the second camera mounting member 88 also move up and down integrally with the first S-axis table 72A and the first camera mounting member 79.

  The distance a (FIG. 4) between the two imaging cameras 55A and 55B is adjusted by driving the S-axis motor 85. That is, when the screw rod 86 is rotated by driving the S-axis motor 85, the nut 87 moves up and down along the screw rod 86, so that the second S-axis table 72B, the second camera mounting member 88, and the imaging camera are moved. 55B also moves up and down, and the interval a between the imaging cameras 55A and 55B is adjusted. In this case, if the interval a between the imaging cameras 55A and 55B is set to 5 times the pitch P (FIG. 5) of the circuit pattern 5 formed on the TAB tape 4, 5 × pitch P in the longitudinal direction of the tape at the time of imaging. Two circuit patterns 5 separated by a distance can be simultaneously imaged by the two imaging cameras 55A and 55B. Further, for example, the movement (imaging) distance in the tape transport direction of each imaging camera 55A, 55B at the time of one imaging is set to 5 × pitch P (= a = b), and the feed amount of the TAB tape 4 is (a + b). If it is set to × 2, each of the imaging cameras 55A and 55B can image a total of 15 circuit patterns 5 with 5 in the tape transport direction and 3 in the tape width direction.

  The focal lengths of the imaging cameras 55A and 55B are adjusted by moving and adjusting the first camera mounting member 79 in the left-right direction by the X-axis motor 80. At this time, since the second camera mounting member 88 also moves together with the first camera mounting member 79, the focal lengths of the two imaging cameras 55A and 55B are adjusted simultaneously.

  The second table mechanism 51B adjusts the distance d between the two imaging cameras 55C and 55D disposed in the ascending conveyance area 21B, adjusts the focal length, etc., and controls the imaging cameras 55C and 55D during imaging. It is moved along the circuit pattern 5. The second table mechanism 51B has the same structure as the first table mechanism 51A, except that the second table mechanism 51B is symmetrically disposed with the first table mechanism 51A and the conveyance path 21 therebetween. Therefore, the description thereof is omitted. Note that the movement (imaging) distances c and d in the tape transport direction during imaging by the imaging cameras 55C and 55D are 5 × pitch P (a = b = c = d) as in the imaging cameras 55A and 55B. Is set.

  Since the TAB tape 4 is usually bent in the width direction of the tape, it is necessary to correct the circuit pattern 5 so as to coincide with the focus of the imaging cameras 55A to 55D by correcting so that a flat surface is formed at the time of imaging. For this reason, the space between the descending conveyance area 21 </ b> A and the ascending conveyance area 21 </ b> B of the conveyance path 21 forms an aperture gate portion 95 that corrects the warp of the TAB tape 5, and the aperture gate portion 95 has the first gate. The second warp correction mechanisms 52A and 52B are arranged back to back. The first warp correction mechanism 52A corrects the warp of the TAB tape 4 traveling in the descending transport area 21A, and is a height position facing the imaging cameras 55A and 55B on the descending transport area 21A side with the TAB tape 4 interposed therebetween. Means for pressing the TAB film 4 against the plate at the time of imaging the circuit pattern 5 (not shown), and means for separating the TAB tape 4 from the plate when the imaging is completed (not shown). Etc.).

  Similarly, the second warp correction mechanism 52B corrects the warp of the TAB tape 4 running in the ascending transport area 21B, and has the same structure as the first warp correction mechanism 52A and is 2 on the ascending transport area 21B side. It is disposed at a height position facing the imaging cameras 55C and 55D of the table and the TAB tape 4 therebetween. Since the first and second warp correction mechanisms 52A and 52B are conventionally known as disclosed in, for example, Patent Document 1 described above, the description of the detailed structure beyond this is omitted. .

  The TAB tape 4 meanders in the width direction (Y direction in FIG. 2) as the span length of the descending conveyance area 21A and the ascending conveyance area 21B becomes longer, and adversely affects imaging by the imaging cameras 55A to 55D. Therefore, the inspection section B is further provided with meandering detecting means 100 (FIG. 1) for detecting meandering in the width direction of the TAB tape 4. The meandering detection and detection means 100 constantly detects one side edge of the TAB tape 4 and sends a detection signal to the control unit. The control unit determines whether or not the TAB tape 4 is meandering in the width direction based on a detection signal from the meandering detection means 100, and if meandering, drives the Y-direction driving motor 35 shown in FIG. By doing so, meandering is corrected. That is, when the TAB tape 4 meanders to the front side of the apparatus, the case 36, the bearing member 32, and the pitch adjusting roller 27 are moved to the rear side of the apparatus by driving the Y direction driving motor 35, and conversely the rear side of the apparatus. In the meantime, the case 36, the bearing member 32, and the pitch adjusting roller 27 are moved to the front side of the apparatus to remove the meandering of the TAB tape 4.

  In FIG. 1, in the buffer part C, a pair of left and right guide rollers 110, 111 and a TAB tape 4 between these guide rollers 110, 111 are placed on the TAB tape 4 by its own weight. A buffer roller 112 is provided to hang down in a shape. The buffer roller 112 is provided so as to be movable up and down between the upper end and the lower end of the guide 113.

  Similarly to the conveyance path 21 of the inspection unit B, the conveyance path 124 between the verify unit D and the NG marking unit E is also formed in a substantially U shape, so that the downward conveyance region 124A, the ascending conveyance region 124B, and the turn-back. Part 124C. The transport means 125 for transporting the TAB tape 4 along the transport path 124 includes a tension sprocket 126, a drive sprocket 127, a pitch adjusting roller 128, and the like, similar to the transport means 22 of the inspection section B. . The pitch adjusting roller 128 is provided so as to be moved and adjusted in the vertical and front-rear directions by the same adjusting mechanism as the adjusting mechanism 30 shown in FIG.

  The verify unit D observes an image of the circuit pattern 5 that has been imaged by the pattern imaging device 23 and is determined to be defective with the verify microscope 120, and whether the circuit pattern 5 is a non-defective product or whether dust is attached. A verification microscope 120 and a warp correction device 121 arranged so as to face each other across the descending conveyance region 124A, a display device such as a CRT, an input device, etc. It consists of When it is determined whether the circuit pattern 5 is a non-defective product (OK) or a defective product (NG) by the verify inspection, the result is sent to the control unit and temporarily stored in the storage unit.

  The NG marking section E is a section for marking an NG circuit pattern by ink, punching, or the like by an NG signal sent from the control section, and is arranged so as to face the rising conveyance area 124B. And a stage 131 having a substantially vertical work surface.

  The winding runner portion F includes a winding reel 140 for winding the TAB tape 4 for which the inspection of the circuit pattern 5 has been completed, a plurality of transport rollers 141, and a slack detection sensor 142 that detects a slack amount of the TAB tape 4. Is provided. Since the slackness detecting means 142 is the same as the slackness detection sensor 12 of the unwinding part A, the detailed description thereof is omitted.

Next, the operation of the automatic pattern inspection apparatus 1 having the above structure will be described based on the flowchart shown in FIG.
First, the type data of the film tape to be inspected is registered in the control unit (step 200). The product data to be registered includes the width of the TAB tape 4, the pitch P of the circuit pattern 5, the number of patterns in the tape width direction, and the like.

  Next, the supply reel 11 around which the TAB tape 4 to be inspected is wound is set on the unwinding runner part A, the leading end part of the TAB tape 4 is pulled out, and the inspection part B, the buffer part C, the verification part D, It leads to the NG station E and the winding runner part F, and is fixed to the winding reel 140 (step 201). The starting end portion that is unwound from the supply reel 11 of the TAB tape 4 is a surplus portion where the circuit pattern 5 is not formed.

The control unit that has obtained information such as the pitch of the circuit pattern 5 by inputting the product data sets the following imaging operation.
In this case, it is set so that each of the imaging cameras 55A to 55D images a plurality of circuit patterns 5 adjacent in the transport direction in one imaging. Here, the arrangement of the patterns 5 in the width direction of the TAB tape 4 is represented by “rows”. For example, an interval a between the imaging cameras 55A and 55B, an interval d between the imaging cameras 55C and 55D is a = d = 5 × pitch P, and a single feed amount of the TAB tape 4 is (a + b) × 2. A circuit pattern captured by each camera by moving each imaging camera 55A to 55D by 3 rows of 5 × pitch P (= a = b = c = d) in the Z direction and circuit pattern 5 in the Y direction during imaging. The number of 5 is 5 in the tape conveyance direction and 3 in the tape width direction, for a total of 15. Accordingly, the imaging areas of the imaging cameras 55A to 55D at the time of imaging are all equal. In FIG. 5, B ₁ indicates the first imaging area of the imaging camera 55B.

  When the imaging cameras 55A to 55D are adjusted by the table device 51, first, the two imaging cameras 55A and 55B on the descending conveyance region 21A side are performed by the first table mechanism 51A. As a procedure, first, the Z-axis motor 73 is driven to move the first S-axis table 72A up and down to adjust the imaging camera 55A to a predetermined height position.

  Next, the S-axis motor 85 is driven to move the second S-axis table 72B, the camera mounting member 88, and the imaging camera 55B up and down to adjust the distance a between the imaging camera 55A. Next, the Y-axis motor 64 is driven to move and adjust the Y-axis table 62 in the front-rear direction, and the imaging cameras 5A and 55B are moved to positions where the circuit pattern 5 can be imaged to adjust the imaging field of view. Then, the X-axis motor 80 is driven to move and adjust the first S-axis table 72A in the left-right direction, and the focal lengths of the two imaging cameras 55A and 55B are adjusted. The adjustment of the imaging cameras 55C and 55D is performed in the same manner as the adjustment of the imaging cameras 55A and 55B, and thus the description thereof is omitted. Then, the pitch adjusting roller 27 is moved up and down by the adjusting mechanism 30, and the distance (tape length) e from the height position at the end of imaging of the imaging camera 55B to the height position at the start of imaging of the imaging camera 55D (tape length) e (FIG. Adjust 4).

  As for the movement in the Z direction of each of the imaging cameras 55A to 55D at the time of imaging, the imaging cameras 55A and 55B are moved downward synchronously, and the imaging cameras 55C and 55D are also moved upward synchronously. The tape length e from the height position at the end of imaging of the imaging camera 55B to the height position at the start of imaging of the imaging camera 55D is set to (a + b) × even times (for example, 4 times).

  When the setting of the imaging operation by the control unit is completed, the start button is turned on. When the start button is turned on, the tape driving motor is driven to intermittently unwind the TAB tape 4 from the unwinding reel 11 (step 203, step 204), and start imaging of the circuit pattern 5 by the pattern imaging device 23. (Step 205, Step 206).

The TAB tape 4 is transported to the inspection unit B and stops when the first circuit pattern 5 passes through the imaging camera 55B and moves downward by 5 × pitch P. In this stopped state, the imaging of the circuit pattern 5 by the imaging camera is stopped. Is done. Upon initial imaging, imaging the imaging camera 55A, by 55B are moved in synchronism with the Z and Y directions, as shown in FIG. 6 (a), the imaging camera 55A is a circuit pattern 5 of the imaging area A ₁ and, an imaging camera 55B captures an image of the circuit pattern 5 of the imaging area B _1, the image is sent to the control unit. Then, when the first imaging is completed, the imaging cameras 55A and 55B return to their original height positions. At this time, the imaging cameras 55C and 55D are stopped because they do not capture the circuit pattern 5.

When the first imaging is completed, the TAB tape 4 is conveyed by (a + b) × 2 (first conveyance) and stopped. The second imaging, as shown in FIG. 6 (b), the imaging camera 55A captures an image of the circuit pattern 5 of the imaging area A _2, the imaging camera 55B captures an image of the circuit pattern 5 of the imaging area B _2, the image Is sent to the control unit. Also at this time, the imaging cameras 55C and 55D are stopped because they do not capture the circuit pattern. There are two non-imaging areas between the imaging area A ₁ and the imaging area B ₂ .

When the second imaging is completed, the TAB tape 4 is conveyed by (a + b) × 2 (second conveyance) and stopped. Imaging the third, as shown in FIG. 6 (c), the imaging camera 55A captures an image of the circuit pattern 5 of the imaging area A _3, the imaging camera 55B captures an image of the circuit pattern 5 of the imaging area B _3, the image Is sent to the control unit. Also at this time, the imaging cameras 55C and 55D are stopped because they do not capture the circuit pattern. There are two non-imaging areas between the imaging area A ₂ and the imaging area B ₃ .

When the third imaging is finished, the TAB tape 4 is conveyed by (a + b) × 2 (third conveyance) and stopped. Fourth imaging, as shown in FIG. 6 (d), the imaging camera 55A captures an image of the circuit pattern 5 of the imaging area A _4, the imaging camera 55B captures an image of the circuit pattern 5 of the imaging area B _4, the image Is sent to the control unit. Further, in the third transport of the TAB tape 4, the two non-imaging areas (C ₁ , D ₁ ) between the imaging area A ₁ and the imaging area B ₂ move to the positions of the imaging cameras 55C and 55D. When these imaging cameras 55C and 55D move in synchronization with the Z direction and the Y direction to capture the imaging areas C ₁ and D ₁ , the images are sent to the control unit.

When the fourth imaging is completed, the TAB tape 4 is conveyed by (a + b) × 2 (fourth conveyance) and stopped. Fifth imaging, as shown in FIG. 6 (e), the imaging camera 55A captures an image of the circuit pattern 5 of the imaging area A _5, the imaging camera 55B captures an image of the circuit pattern 5 of the imaging area B _5, the image Is sent to the control unit. Further, in the fourth transport of the TAB tape 4, the two non-imaging areas (C ₂ , D ₂ ) between the imaging area A ₂ and the imaging area B ₃ move to the positions of the imaging cameras 55C and 55D. When these imaging cameras 55C and 55D respectively capture the imaging areas C ₂ and D ₂ , the images are sent to the control unit.

When the fifth imaging is completed, the TAB tape 4 is conveyed by (a + b) × 2 (fourth conveyance) and stopped. Sixth imaging, as shown in FIG. 6 (f), the imaging camera 55A captures an image of the circuit pattern 5 of the imaging area A _6, the imaging camera 55B captures an image of the circuit pattern 5 of the imaging area B _6, the image Is sent to the control unit. Further, in the fifth transport of the TAB tape 4, two non-imaging areas (C ₃ , D ₃ ) between the imaging area A ₃ and the imaging area B ₄ move to the positions of the imaging cameras 55C and 55D. When these imaging cameras 55C and 55D respectively capture the imaging areas C ₃ and D ₃ , the images are sent to the control unit. Thereafter, imaging of the circuit pattern 5 is repeated in the same manner.

  When the TAB tape 4 that has passed through the inspection section B is sent to the verification section D through the buffer section C (step 207), the image of the circuit pattern 5 that is imaged by the pattern imaging device 23 and determined to be defective is verified. By observing with the microscope 120, it is determined whether the circuit pattern 5 is a non-defective product, whether dust is attached, or the like. When the verify inspection determines whether the circuit pattern 5 is a non-defective product (OK) or a defective product (NG), the result is sent to the control unit and temporarily stored in the storage unit.

  In this way, the verification inspection of the circuit pattern 5 is completed, and the circuit pattern confirmed to be defective is punched by the marking device 130 at the NG marking portion E (step 208). The TAB tape 4 that has passed the NG marking portion E is conveyed to the take-up runner portion F and taken up on the take-up reel 140 (step 209, step 210). Then, when the pattern inspection by the automatic pattern inspection apparatus 1 is completed and the TAB tape 4 is taken up by the take-up reel 140, the take-up reel 140 is taken out from the take-up runner F and conveyed to the next process (step 211). ).

  As described above, in the automatic pattern inspection apparatus 1 according to the present invention, the conveyance path 21 of the inspection unit B is bent in a U-shape, and the four imaging cameras 55A to 55D are moved up and down with the descending conveyance area 21A of the conveyance path 21. Since the two TAB tapes 4 are arranged in the area 21B and the feed amount of the TAB tape 4 is (a + b) × 2, each of the imaging cameras 55A to 55D in one imaging after the third feeding, A total of 15 circuit patterns 5 can be simultaneously imaged in 5 rows in the tape transport direction and 3 rows in the tape width direction, and the inspection time can be greatly reduced. In addition, since the conveyance path 21 is bent in a U shape, the apparatus is compared with the conventional apparatus in which the conveyance path is provided in a straight line in the horizontal direction even though the four imaging cameras 55A to 55D are used. It can be downsized.

  Further, since the conveyance path 21 is bent in a U-shape, the span of the TAB tape 4 in the lower conveyance area 21A and the ascent conveyance area 21B does not become long, the tension mechanism is simple, and the assembly and adjustment work of the apparatus is easy. The predetermined tension can be applied to the TAB tape 4.

  Further, the imaging cameras 55A to 55D are arranged so that the optical axis of the camera is parallel to the surface of the TAB tape 4 and coincides with the front-rear direction of the apparatus, and the reflected light reflected by the TAB tape 4 is reflected by the reflecting mirror 57 to each imaging camera. Therefore, the length of the apparatus in the left-right direction can be further shortened, and the apparatus can be downsized in this respect as well.

  Further, a pitch adjusting roller 27 is provided for adjusting the tape length e (FIG. 4) from the imaging camera 55B in the descending conveyance area 21A to the imaging camera 55D in the ascending conveyance area 21B according to the pitch P of the circuit pattern 5. Therefore, pattern inspection of various TAB tapes having different circuit pattern pitches P can be performed.

  Further, the present invention is provided with meandering detecting means 100 for detecting meandering of the TAB tape 4, and the pitch adjusting roller 27 is moved and adjusted in the direction opposite to the meandering direction of the TAB tape 4 by the detection signal. The meandering of the tape 4 can be reliably corrected, and the TAB tape 4 can be transported in a stable state.

  In the above-described embodiment, the example in which the circuit pattern 5 of the TAB tape 4 is imaged using the four imaging cameras 55A to 55D has been described. For example, six imaging cameras may be provided, and three cameras may be provided in each of the descending conveyance area 21A and the ascending conveyance area 21B.

  The automatic pattern inspection apparatus according to the present invention is not limited to the inspection of the circuit pattern 5 of the TAB tape 4, but can also be used for the pattern inspection of inspection objects such as LCD, ASIC, μBGA, and CSP.

It is a schematic block diagram inside the apparatus which shows one Embodiment of the pattern automatic inspection apparatus which concerns on this invention. It is a perspective view which shows the adjustment mechanism of the roller for pitch adjustment. It is a schematic perspective view of an inspection part. It is a figure which shows the positional relationship and space | interval of an imaging camera. It is a figure which shows a circuit pattern. (A)-(f) is a figure for demonstrating the imaging of the circuit pattern by an imaging camera. It is a flowchart of a pattern inspection.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Automatic pattern inspection apparatus, 4 ... TAB tape, 5 ... Circuit pattern, 21 ... Conveyance path, 21A ... Lowering conveyance area, 21B ... Ascending conveyance area, 21C ... Folding part, 22 ... Conveying means, 23 ... Pattern imaging device, 26 ... tension sprocket, 27 ... drive sprocket, 27 ... pitch adjusting roller, 30 ... adjusting mechanism, 55A to 55D ... imaging camera, 57 ... reflecting mirror, 100 ... meandering detecting means, B ... inspection section.

Claims (3)

An inspection unit having a conveyance path bent in a substantially U shape, a conveyance unit that conveys a tape for mounting electronic components along the conveyance path, and an image of a circuit pattern formed on the tape in the inspection unit A plurality of imaging cameras,
The imaging cameras are installed at least two apart from each other in the traveling direction of the tape with respect to each of the descending conveyance area and the ascending conveyance area of the conveyance path,
The transport means is disposed at the turn-up portion of the transport path so that the height can be adjusted, and the tape length from the imaging camera in the descending transport area to the imaging camera in the ascending transport area corresponding to the pitch of the circuit pattern An automatic pattern inspection apparatus comprising a pitch adjusting roller for adjusting the pitch.   A meandering detecting means for detecting meandering in the width direction of the tape, and means for moving and adjusting the pitch adjusting roller in a direction opposite to the meandering direction of the tape based on a detection signal from the meandering detecting means. The automatic pattern inspection apparatus according to claim 1, wherein: An imaging camera is disposed so that the optical axis of the camera is parallel to the surface of the tape, and includes an optical component that guides light from a light source to the tape and guides reflected light from the tape to the imaging camera. The automatic pattern inspection apparatus according to claim 1 or 2, characterized in that:

Images