JP2010206157A - Method for picking up semiconductor chip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pickup method of a semiconductor chip which can shorten a time of pickup. <P>SOLUTION: The method includes steps of: fetching images (1) of a plurality of semiconductor chips 17 on a resin sheet 15; calculating positions of good-quality chips 17a of the images (1) to select n-th good quality chip 17a; moving the resin sheet 15 with the n-th good-quality chip 17a oriented toward a pickup position; fetching an image (2) around the n-th good-quality chip 17a; calculating an angle and a position of the n-th good-quality chip 17a from the image (2) to compensate the position of the n-th good-quality chip 17a if required; picking up the n-th good-quality chip 17a to a pickup section 33 of a mounting head 31; calculating positions of the good-quality chips 17a of the image (2) to select (n+1)-th good-quality chip 17a; calculating an angle and a position of the (n+1)-th good-quality chip 17a from the image (2) to move the (n+1)-th good-quality chip 17a with the resin sheet 15 oriented toward the pickup position; and picking up the (n+1)-th good-quality chip 17a to an another pickup section 33. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a semiconductor chip pickup method for recognizing and picking up a position of a semiconductor chip in order to mount the semiconductor chip.

  A semiconductor chip on which a semiconductor element is formed is often mounted on a lead frame, a package substrate, or the like to be a semiconductor device. A semiconductor chip is usually subjected to a semiconductor element manufacturing process in a wafer state. Prior to assembling a semiconductor device, the semiconductor wafer is subjected to electrical characteristic measurement and determination, thinning to a suitable thickness, separation into individual semiconductor chips (separation), and the like. A semiconductor chip whose electrical characteristics are determined to be defective is provided with ink or the like as a mark, for example.

  The separated semiconductor chips before being assembled into the semiconductor device are attached to a planar resin sheet in a state of being separated at a substantially constant interval. The semiconductor chips on the resin sheet are arranged in a lattice shape, that is, in rows and columns, at a pitch obtained by adding separation intervals to individual vertical and horizontal dimensions. The semiconductor chip on the resin sheet includes a defective product having electrical characteristics with ink attached thereto, a defective product having a scratch or the like attached in the semiconductor element manufacturing process and the measurement / individualization process. It may fall out during the process.

  In order to recognize and pick up a semiconductor chip on a resin sheet, for example, a step of imaging a plurality of semiconductor chips divided on a wafer with an ITV (Industrial Television) camera, and image information obtained by this step Is processed by the image processing unit, and a step of performing pick-up positioning with respect to any one non-defective chip, and during the pick-up operation by the mount head of the non-defective chip positioned by this step, There has been disclosed a pickup position recognition method having a step of discriminating a non-defective product of a semiconductor chip and a step of determining position information of another non-defective chip discriminated by this step (for example, see Patent Document 1). That is, this is a pickup position recognition method in which an image is captured once before the pickup of one semiconductor chip.

  The disclosed pickup position recognition method is suitable for a method in which a semiconductor chip is picked up by one pickup portion and one of them is mounted. However, the method of mounting semiconductor chips one by one is defined as the later time of either the time from image acquisition to image processing or the time from pickup to mounting, and cannot be faster than that. If you try to mount multiple semiconductor chips at the same time by installing multiple pickup parts, for each semiconductor chip, from image capture, calculation of non-defective chip position, movement to mount position, and until pickup permission In addition to taking time, there is a problem that it is difficult to shorten the time of the mounting process because it is necessary to retract the mounting head for the next image acquisition after picking up one semiconductor chip.

JP 2004-153050 A

  The present invention provides a method of picking up a semiconductor chip that can shorten the time.

  According to another aspect of the present invention, there is provided a method of picking up a semiconductor chip, imaging a region where a plurality of semiconductor chips arranged on a sheet enter a field of view to obtain first image data; Calculating and storing a position of a non-defective semiconductor chip, selecting a first semiconductor chip among the non-defective semiconductor chips, and position information of the first semiconductor chip based on the position information of the first semiconductor chip Moving the sheet so that the chip can be picked up; obtaining second image data of a region entering the field of view around the first semiconductor chip; The angle and position of the first semiconductor chip are calculated based on the image data of 2, and it is confirmed whether the first semiconductor chip is in a position where it can be picked up. If not, the step of correcting the position, the step of picking up the first semiconductor chip by the first pickup unit of the pickup means provided with at least two pickup units, and the second image data Calculating and storing a position of a non-defective semiconductor chip, selecting a second semiconductor chip among the non-defective semiconductor chips, calculating an angle and a position of the second semiconductor chip, A step of moving the sheet so that the second semiconductor chip can be picked up, and a step of picking up the second semiconductor chip by the second pickup portion of the pickup means. Features.

  According to another aspect of the present invention, there is provided a method of picking up a semiconductor chip, imaging a region in which a plurality of semiconductor chips arranged on a sheet enter a field of view to obtain first image data, and the first image data. Calculating and storing a position of a non-defective semiconductor chip, selecting a first semiconductor chip among the non-defective semiconductor chips, and the first semiconductor chip following the first semiconductor chip. Moving to an off-center position so as to have more of the semiconductor chips in the field of view in the picked-up direction, imaging a region including the first semiconductor chip in the field of view, and obtaining second image data; , Calculating the angle and position of the first semiconductor chip based on the second image data, moving to a position where it can be picked up, and reducing the amount of the first semiconductor chip. Both the step of picking up by the first pick-up part of the pick-up means provided with two pick-up parts, the position of the good semiconductor chip in the second image data are calculated and stored, and the good semiconductor Selecting a second semiconductor chip in the chip, calculating an angle and a position of the second semiconductor chip, and moving the sheet so that the second semiconductor chip can be picked up And a step of picking up the second semiconductor chip by a second pickup portion of the pickup means.

  According to the present invention, it is possible to provide a semiconductor chip pick-up method capable of reducing time.

1 is a block diagram schematically showing the configuration of a semiconductor chip pickup device according to a first embodiment of the invention. 3 is a flowchart schematically showing a semiconductor chip pickup process according to the first embodiment of the present invention. The figure which shows typically the image which imaged the resin sheet in which the semiconductor chip based on Example 1 of this invention was arranged from upper direction. The figure which shows typically the process of the pick-up of the semiconductor chip pick-up apparatus which concerns on Example 1 of this invention. The figure which shows typically the process of FIG. 4 of the pick-up of the semiconductor chip pick-up apparatus which concerns on Example 1 of this invention. 9 is a flowchart schematically showing a semiconductor chip pickup process according to the second embodiment of the present invention. It is a figure which shows typically the image which imaged the resin sheet with which the semiconductor chip based on Example 2 of this invention was arranged from upper direction, and time passes in order of Fig.7 (a), (b), (c) Illustration.

  Embodiments of the present invention will be described below with reference to the drawings. In the figure shown below, the same code | symbol is attached | subjected to the same component.

  A method for picking up a semiconductor chip according to the first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the semiconductor chip pickup device 1 is roughly configured by a stage 11, an ITV camera 21, a mount head 31, an image processing unit 41, a drive control unit 43, and an image monitor 51. The mount head 31 serving as pickup means has four pickup portions 33.

  The stage 11 includes a lower stage 11a and an upper stage 11b, and includes a support column 11c that fixes the lower and upper stages 11a and 11b in the vertical direction. The upper stage 11b can hold the resin sheet 15 having the upper surface maintained substantially horizontal and having the semiconductor chip 17 attached to the upper surface. The stage 11 has a plane coordinate origin at a point in the stage 11 or on the stage 11, for example, a center (on a vertical line passing through the center of a push-up pin 37 described later), and a drive unit that controls the movement of the resin sheet 15 with respect to the coordinate origin. (Not shown) is provided. The resin sheet 15 can move in parallel (X, Y) and in rotation (θ) in a horizontal plane on the upper stage 11b.

  The resin sheet 15 is a flat sheet made of a transparent or translucent resin, has adhesiveness, and can fix the separated semiconductor chip 17. The semiconductor chips 17 on the resin sheet 15 are spaced apart at a substantially constant interval and arranged in rows and columns. The semiconductor chip 17 is often affixed in a state where the semiconductor wafer is cut and formed by stretching the resin sheet 15 in the planar direction.

  The semiconductor chip 17 on the resin sheet 15 includes a defective product having electrical characteristics to which ink or the like is attached, a defective product having scratches / chips or the like attached in a semiconductor element manufacturing process and a measurement / separation process. . In some cases, the semiconductor chip 17 falls off during the process, and a void is formed on the resin sheet 15.

  The ITV camera 21 has an image sensor (not shown) made of a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) or the like, and has a field of view (view angle) that can be imaged by the size of the image sensor and the lens used. Also called). For example, the image sensor is a rectangle or a rectangle close to a rectangle.

  The ITV camera 21 is compared with a device having one pickup unit so that the semiconductor chip 17 can be sequentially picked up by the four pickup units 33, that is, enough to be resolved even if the imaging area is widened. For example, the number of pixels of the image sensor is increased from 4 times to 16 times. The ITV camera 21 has an optical axis perpendicular to the horizontal plane of the upper stage 11 b and at the center of the stage 11. The ITV camera 21 is focused on the semiconductor chip 17 on the upper stage 11b.

  The semiconductor chip 17 is placed at the center of the stage 11 (pickup position 20, directly below the ITV camera 21) and picked up.

  A lighting device 23 is disposed in the vicinity of the ITV camera 21. The illumination device 23 selects a shape, a position, a wavelength of a light source, and the like so as not to disturb imaging and to easily detect an abnormality in the outer shape and surface of the semiconductor chip 17.

  The image processing unit 41 captures an image of the semiconductor chip 17 on the resin sheet 15 picked up by the ITV camera 21, and through image processing, the presence / absence of a pickup target and its surrounding semiconductor chip 17, presence / absence of a chip or a scratch, electrical characteristics The presence / absence of a mark (ink) indicating a defect can be determined from the appearance. Further, the position of the semiconductor chip 17 is represented by, for example, the position of the center of gravity, and is calculated with respect to the coordinate origin of the stage 11, and the inclination of the semiconductor chip 17 with respect to the X axis or the Y axis is calculated. The calculated information such as the pass / fail judgment result and position of the semiconductor chip 17 is stored in the memory of the image processing unit 41.

  The image processing unit 41 also has a table (pickup order table) for instructing the priority of the pickup order created based on the information of the semiconductor chip 17. In addition, a table storing non-defective chips (non-defective chip storage table), a table storing non-defective chip positions (non-defective chip position table), a table storing non-defective chips after pickup execution (remaining non-defective chip storage table), etc. Has been created.

  The image monitor 51 is connected to the image processing unit 41. On the image monitor 51, images picked up by the ITV camera 21 are displayed in real time, images for each step of image processing, pickup order table after image processing, non-defective chip storage table, non-defective chip position table, and remaining A non-defective chip storage table or the like is displayed in a desired format, for example, in a table or a plane layout. The image monitor 51 can display 100% of the field of view of the ITV camera 21.

  The mount head 31 has a plurality of pickup units 33, for example, four pickup units 33 for simultaneously transporting four semiconductor chips 17 so that the plurality of semiconductor chips 17 can be transported simultaneously. The mount head 31 is attached to a moving mechanism (not shown) such as an arm, and can move between a pickup position, a mount position, and a retracted position. The pickup unit 33 can move in the vertical (Z) direction. A push-up pin 37 for pushing up the semiconductor chip 17 is disposed directly below the pickup position. The mount head 31 will be further described later.

  The stage 11, the mount head 31, and the image processing unit 41 are connected to the drive control unit 43. In order to move the semiconductor chip 17 to the pickup position, the amount to be moved (correction data) calculated by the image processing unit 41 is sent to the drive control unit 43. The drive control unit 43 controls the movement of the stage 11 based on the amount to be moved, and controls the pickup operation by the mount head 31 and the push-up pin 37. The drive control unit 43 further controls the movement of the mount head 31 to the mount position, the mount operation, and the like. That is, the drive control unit 43 controls the stage 11, the ITV camera 21, the image processing unit 41, the mount head 31, and the like so that there is no mechanical interference, optical interference, or the like.

  Next, the pickup operation of the semiconductor chip pickup device 1 will be described. FIG. 2 shows, as a schematic flowchart, steps such as image capture, search, and movement of the semiconductor chip mounted on the resin sheet 15 on the stage 11 on the right side, and movement of the mounter head 31 on the left side.

  As shown in FIG. 2, the semiconductor chips 17 arranged in a lattice pattern on the resin sheet 15 are arranged at predetermined positions on the stage 11, and predetermined by the ITV camera 21 on the resin sheet 15. An area having a plurality of non-defective semiconductor chips 17 (non-defective chips 17a), at least four, is imaged, and image data (1) (image (1) in FIG. 2) as first image data is captured (step 1). S11). However, there may be a case where four or more non-defective chips 17a are not present in the peripheral portion of the array or the portion with a low non-defective product rate.

  The imaging area is an area where 7 × 7 semiconductor chips 17 are placed. In addition, when the non-defective chip 17a is arranged at the pickup position 20, it is appropriate that the imaging area is an area where at least 3 × 3 semiconductor chips 17 are placed when imaging a plurality of semiconductor chips 17. . Usually, a plurality of non-defective chips 17a often exist in an area where 7 × 7 semiconductor chips 17 are placed.

  Since the non-defective chip 17a is mounted with the number of pickup units 33 being four, the number of non-defective chips 17a is managed. The number of non-defective chips 17a is, for example, M (at the start, M = 0). M is managed by the drive control unit 43 together with the control of the stage 11 and the mount head 31, and is sent as a request command to the image processing unit 41 based on M. In the flowchart of FIG. 2, M is described as being incorporated in the program.

  The mount head 31 is controlled by the drive control unit 43 and is placed at a position that does not hinder the imaging by the ITV camera 21, for example, a retracted position. The retracted position is a position that does not interfere with preparation operations necessary for imaging and mounting by the ITV camera 21.

  A rough search is performed, the non-defective chip 17a in the image data (1) is selected, the approximate position of the non-defective chip 17a is calculated and stored, and the nth semiconductor chip, which is the first semiconductor chip in the good chip 17a, is calculated. Items are selected according to a predetermined procedure (step S12). For example, the n-th non-defective chip 17a closest to the center position of the image data (1) is selected from the plurality.

Position information to be moved of the n-th non-defective chip 17 a is sent to the drive control unit 43, and the drive control unit 43 controls the stage 11 to pick up the n-th non-defective chip 17 a on the resin sheet 15. The possible pickup position 20, that is, the center position of the screen is moved to the target (step S13). (M increases by 1 and M = 1)
Judgment is made by a remainder (remainder) obtained by dividing M by 4 (step S14). The nth non-defective chip 17a corresponding to M = 1 has a remainder of 1.

  Image data (K) that is second image data in the same area as the image data (1) around the n-th non-defective chip 17a. (In this case, it becomes image data (2)) (step S15). As shown in FIG. 3, an image of an area on which 7 × 7 semiconductor chips 17 arranged around the n-th non-defective chip 17a are placed is obtained.

  A rectangle whose outer shape is indicated by a solid line indicates a semiconductor chip 17, and the semiconductor chip 17 is divided into a non-defective chip 17a and a defective chip 17b. A rectangle whose outer shape is indicated by a dotted line indicates a chip mark 19. The chip mark 19 indicates a position where the semiconductor chip 17 has been picked up, dropped during the process, or removed in advance. The defective product chip 17b having the abnormal surface portion 18, which is determined to be defective by the general search, is left on the resin sheet 15. The abnormal surface portion 18 is ink that is determined to be defective by electrical property evaluation, cracks, chips, scratches, dirt, etc. on the surface. In addition, although illustration is omitted, those having dimensions outside the allowable range are also regarded as defective.

  The code given to the surface of the non-defective chip 17a is based on the pickup order table, and the n + 1th non-defective chip 17a is picked up after the nth non-defective chip 17a. In FIG. 3, n + 4th non-defective chips 17a are shown. However, all the non-defective chips 17a in the image data (2) are given order codes.

  A detailed search is performed to calculate and store the angle and position of the nth non-defective chip 17a in the image data (2) (step S16). The position information of the non-defective chip 17a obtained from the image data (1) is replaced. Since the image data (2) is obtained with the nth non-defective chip 17a closer to the center, the error is smaller than the position information obtained with the image data (1).

  It is determined whether the angle and position of the nth non-defective chip 17a are within the allowable range as the pickup position (step S17).

  If the angle and position of the n-th non-defective chip 17a are not within the allowable range with respect to the pickup position, the position information to be moved obtained in step S16 is sent to the drive control unit 43, and the drive control unit 43 moves the stage 11 over. By controlling, the pickup position 20, that is, the center position of the screen is moved to the target with the n-th non-defective chip 17a placed on the resin sheet 15 (step S18).

  When the movement of the n-th non-defective chip 17a is confirmed, a signal permitting pickup is sent to the drive control unit 43 (step S19). If it is determined in step S17 that the angle and position of the nth non-defective chip 17a are within the allowable range with respect to the pickup position, the pickup in step S19 is performed without moving the nth nondefective chip 17a. A signal to permit is sent to the drive control unit 43.

  As shown in FIG. 4A, when a signal for permitting pickup is sent, the mount head 31 is controlled by the drive control unit 43 and picks up the nth non-defective chip 17 a by the pickup unit 33. The mount head 31 can be moved to the pickup position after the image data (2) is captured. The non-defective chip 17a placed at the pickup position is pushed up from the bottom of the resin sheet 15 by the push-up pin 37 located at the position of the center of gravity.

  The mount head 31 includes four pickup units 33 each including a collet 34 that sucks the semiconductor chip 17 from above and a collet driving unit 35 that drives the collet 34 in the vertical direction in a straight line (left and right direction on the paper surface). Has been. As shown in FIG. 4A, the n-th non-defective chip 17 a pushed up by the push-up pin 37 is adsorbed by, for example, a collet 34 of the pickup unit 33 at the left end of the paper surface of the mount head 31. Note that the four pickup portions 33 are not necessarily arranged in a straight line. The mount head 31 stays at the pickup position until all the four pickup parts 33 have been picked up.

  Based on the image data (2), a rough search of the (n + 1) th non-defective chip 17a and the non-defective chip 17a to which the number greater than n + 1 is given is performed, and a rough position is calculated and stored, and the (n + 1) th non-defective chip 17a is calculated. Are selected (step S20). The picked-up n-th non-defective chip 17a is excluded from the image data (2) for image processing. The position information obtained from the image data (1) is replaced.

  It is determined whether or not the (n + 1) th non-defective chip 17a exists in the image data (2) (step S21). As shown in FIG. 3, there is an (n + 1) th non-defective chip 17a.

  A detailed search of the (n + 1) th non-defective chip 17a in the image data (2) is performed, and the angle and position are calculated and stored (step S22). The error in the angle and position of the n + 1th non-defective chip 17a at the adjacent position calculated based on the image data (2) picked up with the nth non-defective chip 17a as the center is small. The inventor has confirmed that the non-defective chip 17a captured in the image data (2) can be accurately moved to a position where it can be picked up based on the position information calculated from the image data (2).

The position information to be moved of the (n + 1) th non-defective chip 17a is sent to the drive control unit 43, and the drive control unit 43 controls the stage 11 to pick up the n + 1th non-defective chip 17a in a state where it is placed on the resin sheet 15. The position 20, that is, the center position of the screen is moved to the target (step S13). (M increases by 1 and M = 2)
Judgment is made by a remainder (remainder) obtained by dividing M by 4 (step S14). The remainder of the (n + 1) th non-defective chip 17a corresponding to M = 2 is 2.

  After the movement of the (n + 1) th non-defective chip 17a, a signal for permitting pickup is sent to the drive control unit 43 (step S23).

  The mount head 31 is controlled by the drive control unit 43 and stands by above the pickup position 20, and the n + 1th non-defective chip 17 a is, for example, the second pickup unit from the left side of the drawing shown in FIG. Pick up by 33.

  It is determined whether or not the non-defective chip 17a is present in the image data (2) (step S21), the process proceeds to step S22, and thereafter, the n + 2th non-defective chip 17a is performed in the same procedure as the above-described n + 1th non-defective chip 17a. Is picked up.

  The (n + 3) th non-defective chip 17a is picked up by the same procedure as the (n + 2) th non-defective chip 17a.

  As shown in FIG. 4B, all the four pickup portions 33 of the mount head 31 are in the pickup state. The mount head 31 is controlled by the drive control unit 43 and is moved to the mount position when all the mount heads 31 are in the pickup state.

  As shown in FIG. 5, the mount head 31 is controlled by the drive control unit 43 to convey the picked up non-defective chip 17 a onto a lead frame 63 provided at a location different from the stage 11. Thereafter, four non-defective chips 17a are mounted simultaneously. The lead frame 63 is disposed on the mount base 61 at the same interval as that of the pickup unit 33, and a liquid paste 65 for bonding or bonding is disposed at a position where the non-defective chip 17a is mounted.

  When the mounting is completed, the mount head 31 is controlled by the drive control unit 43 and moved to the retracted position.

  The n + 4th non-defective chip 17a is advanced to step S13 by the same procedure as the n + 3th non-defective chip 17a, but M = 5, and the remainder obtained by dividing M by 4 is 1 (step S14).

  The n + 4th non-defective chip 17a is advanced in the same procedure as the nth non-defective chip 17a. That is, next, the image data (K) (K = 3, where the n + 4th non-defective chip 17a is approximately the center and in the same area as the surrounding image data (2) is referred to as image data (3). ) Is obtained (step S15). In the image data (3), an image of an area on which 7 × 7 semiconductor chips 17 placed around the n + 4th non-defective chip 17a are placed is obtained. Subsequent steps S16 to S23 are performed in the same procedure as the above-described nth to n + 3 non-defective chips 17a.

  When most of the non-defective chips 17a obtained from one wafer are picked up and mounted as described above, the non-defective chips 17a often do not exist in the image data (K).

  If the non-defective chip 17a does not exist in the image data (K) subjected to the rough search, the image data (K) is repeatedly fetched until the non-defective chip 17a is converted into data, and the remaining good chip storage table or the like is searched. (Step S24).

If there is a good chip 17a left on the resin seal 15 without being picked up, position information on which the good chip 17a is to be moved is sent to the drive control unit 43, and the drive control unit 43 controls the stage 11 and remains. The non-defective chip 17a is moved to the pickup position 20, that is, the center position of the screen (step S25). (M is increased by 1.)
The remaining non-defective chips 17a are likely to be located away from the non-defective chips 17a picked up immediately before, or the surrounding non-defective chips 17a are picked up and the surrounding environment is highly likely to change greatly. For this reason, in order to increase the position accuracy, new image data is captured (step S15). The mount head 31 searches for a non-defective chip 17a to be picked up, and when it is necessary to fetch new image data, it is controlled by the drive control unit 43 and temporarily retracts.

  After the image data is newly taken in, it can be picked up by the same procedure as the n-th non-defective chip 17a.

  If no good chip 17a is found in the search, the process is temporarily stopped. Even if the number of picked-up non-defective chips 17a is less than four, for example, it is possible to switch to manual operation for mounting.

  As described above, the semiconductor chip pick-up method prepares the mount head 31 capable of simultaneously transporting a plurality of non-defective chips 17a, and several of the non-defective chips 17a, for example, four are simultaneously picked up. Based on the image data, it is placed on the resin sheet 15 and moved to the pickup position. In other words, the first one of the four non-defective chips 17a calculates the approximate position by the approximate search, moves based on the calculated data, takes in the image data, performs the detailed search, and moves to the pickup position. Confirm that there is, but for the other three, perform a detailed search using the image data captured in the first one, and place it on the resin sheet 15 to move, so that the pickup allowable range It is possible to move in.

  As a result, the semiconductor chip pick-up method of the present embodiment can reduce the number of times of image capturing compared with the pick-up method of capturing one image before picking up one semiconductor chip. The time can be shortened including this time. In addition, a plurality of non-defective chips 17a are picked up by a single mounting head 31 and transported at a time, so that a plurality of non-defective chips 17a can be mounted at the same time, thereby shortening the time required for mounting the non-defective chips 17a. Is also possible.

  A method for picking up a semiconductor chip according to the second embodiment of the present invention will be described with reference to FIGS. The first embodiment is different from the first embodiment in that a non-defective chip is placed at an off-center position shifted from the pickup position (center position) in order to efficiently fit the semiconductor chip into one image. In the following, the same components as those in the first embodiment are denoted by the same reference numerals, description thereof will be omitted, and different components will be described.

  Although not shown, the semiconductor chip pickup device of the present embodiment has the same configuration as that of the semiconductor chip pickup device 1 of the first embodiment, and has an image sensor with a small number of pixels of the ITV camera 21, for example, the pixel pitch is the same. An image sensor with about half the area is used. Although the field of view of the ITV camera 21 is narrow, it is possible to mount, for example, 5 × 5 semiconductor chips 17 in the imaging region with substantially the same resolution as in the first embodiment. In this example, the image monitor 51 displays the field of view of the ITV camera 21 as 100%.

  Next, the pickup operation will be described. Since the movement of the mounter head 31 is the same as that in the flowchart of the first embodiment, it is omitted in FIG.

  As shown in FIG. 6, the image data (1) is captured through steps S11 and S12, and the nth non-defective chip 17a is selected. Next, with the n-th non-defective chip 17a being placed on the resin sheet 15, M is increased by 1 to M = 1 (step S31). As shown in FIG. 7A, the n-th non-defective chip 17a is on the monitor screen 72, for example, at the center of the monitor screen 72, that is, at a position close to the pickup position 20. The imaging area is an area where 5 × 5 semiconductor chips 17 are placed.

  In step S14, the remainder becomes 1. Based on the calculation of the n-th non-defective chip 17a and the stored approximate position, the amount to be moved is sent to the drive control unit 43, and the drive control unit 43 controls the stage 11 to The non-defective chip 17a is moved to an arbitrarily set off-center position while being placed on the resin sheet 15 (step S32). When placed at the off-center position, the n-th non-defective chip 17 a does not protrude from the monitor screen 72.

  As shown in FIG. 7B, the off-center position 70 is shifted from the pickup position 20, and the n-th non-defective chip 17 a is placed at the off-center position 70, whereby the (n + 1) -th non-defective chip 17 a is displayed on the monitor screen 72. , That is, a position that can be efficiently accommodated in the field of view of the ITV camera 21.

  The off-center position 70 is roughly determined by which direction the pickup is sequentially performed. For example, when picking up sequentially from the left to the right of the monitor screen 72, the off-center position 70 is the left end of the monitor screen 72, and when picking up sequentially from the top to the bottom of the monitor screen 72, the off-center position 70 is It becomes the upper end of the screen 72. Here, since it is programmed to pick up the monitor screen 72 sequentially from the left to the right and then pick up the monitor screen 72 from the top to the bottom, the off-center position 70 is the upper left end. The off-center position 70 is not limited to the upper left end portion of the monitor screen 72. For example, the off-center position 70 is a quadrature monitor screen 72, that is, a line connecting the center position of the quadrangular field of view and the corners of the four corners. Often in the vicinity.

  In the state shown in FIG. 7B, the image data (2) (K = 2) in step S15 is obtained. When placed at the off-center position 70, four columns of semiconductor chips 17 are placed on the right side of the nth non-defective chip 17a, and four rows of semiconductor chips 17 are placed on the lower side, and a total of 25 semiconductor chips 17 are obtained on the monitor screen 72. It is done. For example, on the right side of the nth non-defective chip 17a, the (n + 1) th, n + 2nd, n + 3th, and n + 4th nondefective chip 17a are arranged in order.

  A detailed search in step S16 is performed, and the angle and position of the nth non-defective chip 17a in the image data (2) are calculated and stored. The position information of the non-defective chip 17a obtained from the image data (1) is replaced. The image data (2) is obtained by placing the n-th non-defective chip 17a on the upper left, but using only the central part near the optical axis as compared with the image data (2) of the first embodiment. Therefore, the aberration of the lens is small and the overall error is small. However, in order to reduce the reading error of the n-th non-defective chip 17a located at the off-center position 70 farthest from the optical axis, it is possible to perform correction by incorporating aberration correction of the lens or the like in advance.

  As shown in FIG. 7C, the amount to be moved obtained in step S16 is sent to the drive control unit 43, and the drive control unit 43 controls the stage 11 so that the nth non-defective chip 17a is displayed on the screen. It is moved to the center position, that is, the pickup position 20 (step S33).

  In step S19, the nth non-defective chip 17a is picked up. Thereafter, in step S20, the (n + 1) th non-defective chip 17a is selected, and after steps S21, S22, S31, S14, S33, and S19, the (n + 1) th non-defective chip in the image data (2) is selected. 17a is picked up.

  Similarly, the (n + 2) th non-defective chip 17a and then the (n + 3) th non-defective chip 17a are picked up.

  As described above, when the image data (1) is started and a rough search is performed and the first n-th non-defective chip 17a in the image data (1) is selected, the n-th non-defective chip is selected. 17a is shifted to the off-center position 70, and the image data (2) is captured. Based on the image data (2), position information such as the angle and position of the semiconductor chip 17 required for picking up the mount head 31 is calculated and stored. Accordingly, the non-defective chip 17a is moved to the pickup position 20 at the time of pickup and then picked up. The image data (2) is obtained from an imaging region in which 5 × 5 semiconductor chips are arranged in parallel in the right direction and the downward direction from the n-th non-defective chip 17a placed at the off-center position 70 in the upper left. It is done.

  As a result, the semiconductor chip pick-up method of the present embodiment requires a longer movement time for the movement of the first n-th non-defective chip 17a picked up by the mount head 31 compared to the process of the first embodiment. However, the other non-defective chips 17a have almost the same travel time.

  Since the semiconductor chip pickup device of this embodiment places the non-defective chip 17a at the off-center position 70 and captures an image, the number of pixels of the image sensor of the ITV camera 21 is small, and the imaging area is configured to be small. It is not necessary to use a high-priced high-pixel camera, and the price can be reduced compared to the semiconductor chip pickup device 1 of the first embodiment. Further, since the scale of the image data is reduced, the image processing time is shortened. The time from taking the image data (1) to the end of mounting is almost the same as the semiconductor chip pickup method of the first embodiment.

  In addition, the semiconductor chip pickup method of the present embodiment has the same effects as the semiconductor chip pickup method of the first embodiment.

  Further, as the first modification, the following combinations are possible. That is, although not shown, the semiconductor chip pickup device 1 of the first embodiment is used as it is except that the pickup portion of the mount head is increased. There are, for example, doubled pickup parts of the mount head. Similar to the pickup method of the second embodiment, the first n-th non-defective chip is shifted to, for example, the upper left off-center position, and image data (K, K ≧ 2) is taken in. Six columns of semiconductor chips are placed on the right side of the n-th non-defective chip and six rows of semiconductor chips are placed on the lower side, and a total of 49 semiconductor chips are obtained in the imaging area, that is, the monitor screen.

  Then, the mounting process is changed so that the eight pickup parts of the mount head move the mount head to the mount position after each non-defective chip has been picked up.

  As a result, in the first modification, the semiconductor chip can be put in the entire field of view, so that the maximum of about twice as many semiconductor chips as the image data (K, K ≧ 2) compared with the semiconductor chip pickup method of the second embodiment. As a result, the number of times image data (K, K ≧ 2) can be taken can be reduced, and the time required for picking up a semiconductor chip can be reduced.

  Further, as the second modification, the following combinations are possible. That is, although not shown in the drawing, the semiconductor chip pickup device 1 of the first embodiment remains the same except that only the lens of the ITV camera is changed to a narrow field of view so that the same imaging region as the imaging region of the second embodiment is captured. use.

  Then, as in the method of the second embodiment, the first n-th non-defective chip is shifted to, for example, the upper left off-center position, and image data (K, K ≧ 2) is captured. Four columns of semiconductor chips are placed on the right side of the n-th non-defective chip and four rows of semiconductor chips are placed on the lower side, and a total of 25 semiconductor chips are obtained in the imaging region, that is, the monitor screen. The method of picking up the semiconductor chip is the same as the method of the second embodiment.

  As a result, in the second modification, it is possible to increase the resolution and capture almost the same number of semiconductor chips as image data (K, K ≧ 2) as compared with the semiconductor chip pickup method of the second embodiment. Data with higher accuracy such as the angle and position of the semiconductor chip can be obtained, the accuracy of the pick-up position can be improved, and pick-up defects and related mounting defects can be reduced. Compared with the method for picking up a semiconductor chip of the second embodiment, the image processing time is increased by increasing the resolution, but in addition, the same effects as the method for picking up the semiconductor chip of the second embodiment are provided. .

  As mentioned above, this invention is not limited to the said Example, In the range which does not deviate from the summary of this invention, it can change and implement variously.

  For example, in the embodiments and the modified examples, the semiconductor chips are described as being arranged on the resin sheet in rows and columns at almost regular intervals. However, the semiconductor chips are not necessarily arranged in rows and columns at regular intervals. Also can be picked up. However, if the angle or the like is greatly deviated, it may take time to correct the position.

  In the embodiment and the modification, the mount head has been described as having four or eight pickup units. However, the number of the pickup units is not limited to four or eight, for example, two or more. Is possible. It is possible to make the image data capture range (field of view, imaging region) suitable for the number of pickup units.

  In the embodiment and the modified example, an example in which ink is applied to a defective semiconductor chip has been described. However, an optically distinguishable mark, for example, a concave scratch is formed on the surface of the semiconductor chip, or the reflectance is changed. It is possible to make it.

The present invention can be configured as described in the following supplementary notes.
(Additional remark 1) The process which images the area | region where several semiconductor chips arranged on the sheet | seat enter into a visual field, and obtains 1st image data, and the position of the non-defective semiconductor chip in said 1st image data are calculated And storing and selecting the first semiconductor chip among the non-defective semiconductor chips and the position information of the first semiconductor chip so that the first semiconductor chip can be picked up. The step of moving the sheet, the step of obtaining the second image data of the region entering the visual field around the first semiconductor chip, and the second image data based on the second image data. Calculating an angle and a position of the first semiconductor chip, checking whether the first semiconductor chip is in a position where pickup is possible, and correcting the position if not in a position where pickup is possible; A step in which the first semiconductor chip is picked up by the first pick-up unit of the pick-up means provided with at least two pick-up units, and a position of a good semiconductor chip in the second image data is calculated and The step of storing and selecting the second semiconductor chip among the non-defective semiconductor chips, and calculating the angle and position of the second semiconductor chip so that the second semiconductor chip can be picked up. A method of picking up a semiconductor chip, comprising: moving the sheet to a second position; and picking up the second semiconductor chip by a second pickup portion of the pickup means.

(Supplementary Note 2) While the step of picking up the first semiconductor chip by the first pickup unit is being executed, the step of selecting the second semiconductor chip among the non-defective semiconductor chips is executed The method for picking up a semiconductor chip according to Supplementary Note 1.

(Supplementary Note 3) If no good semiconductor chip is left in the second image data, an image is taken before obtaining the second image data to search for a good semiconductor chip in which the position is stored. The method of picking up a semiconductor chip according to appendix 1, wherein a step of moving the retrieved good semiconductor chip to a position where it can be picked up is further executed.

(Additional remark 4) The said 1st and 2nd image data are the pick-up methods of the semiconductor chip of Additional remark 1 which are imaging the area | region where the semiconductor chip of at least 3 rows 3 columns is arranged.

(Supplementary note 5) The method for picking up a semiconductor chip according to supplementary note 1, further comprising a step in which the first and second semiconductor chips picked up by the pickup means are simultaneously transported and placed in a mount region.

(Supplementary Note 6) The fetching of the first and second image data, the movement of the sheet, the calculation and storage of the position of a non-defective semiconductor chip, and the operation of the pickup means are integrally controlled in Supplementary Note 1. A method for picking up a semiconductor chip as described.

DESCRIPTION OF SYMBOLS 1 Semiconductor chip pick-up apparatus 11 Stage 11a Lower stage 11b Upper stage 11c Support | pillar 15 Resin sheet 17 Semiconductor chip 17a Non-defective chip 17b Defective chip 18 Surface abnormal part 19 Chip trace 20 Pick-up position 21 ITV camera 23 Illumination device 31 Mount head 33 Pick-up part 34 Collet 35 Collet Drive Unit 37 Push-up Pin 41 Image Processing Unit 43 Drive Control Unit 51 Image Monitor 52, 72 Monitor Screen 61 Mount Stand 63 Lead Frame 65 Paste 70 Off-Center Position

Claims (5)

Imaging a region in which a plurality of semiconductor chips arranged on a sheet enter a visual field, and obtaining first image data;
Calculating and storing a position of a good semiconductor chip in the first image data, and selecting a first semiconductor chip in the good semiconductor chip;
Moving the sheet so that the first semiconductor chip can be picked up based on the position information of the first semiconductor chip;
Obtaining a second image data of a region entering the field of view around the first semiconductor chip substantially at the center;
Based on the second image data, the angle and position of the first semiconductor chip are calculated to check whether the first semiconductor chip is at a position where pickup is possible. A step of correcting the position;
A step of picking up the first semiconductor chip by a first pick-up part of pick-up means provided with at least two pick-up parts;
Calculating and storing a position of a good semiconductor chip in the second image data, and selecting a second semiconductor chip in the good semiconductor chip; and
Calculating the angle and position of the second semiconductor chip, and moving the sheet so that the second semiconductor chip can be picked up;
A step of picking up the second semiconductor chip by a second pickup portion of the pickup means;
A method of picking up a semiconductor chip, comprising: Imaging a region in which a plurality of semiconductor chips arranged on a sheet enter a visual field, and obtaining first image data;
Calculating and storing a position of a good semiconductor chip in the first image data, and selecting a first semiconductor chip in the good semiconductor chip;
The first semiconductor chip is moved to an off-center position so as to have more semiconductor chips in the field of view in the direction of picking up following the first semiconductor chip, and the first semiconductor chip in the field of view Capturing a region including, and obtaining second image data;
A step of picking up the first semiconductor chip by a first pick-up part of pick-up means provided with at least two pick-up parts;
Calculating and storing a position of a good semiconductor chip in the second image data, and selecting a second semiconductor chip in the good semiconductor chip; and
Calculating the angle and position of the second semiconductor chip, and moving the sheet so that the second semiconductor chip can be picked up;
A step of picking up the second semiconductor chip by a second pickup portion of the pickup means;
A method of picking up a semiconductor chip, comprising:   3. The method of picking up a semiconductor chip according to claim 2, wherein the off-center position is on or in the vicinity of a line connecting a center position and a corner portion of the visual field having a quadrangular shape.   While the step of picking up the first semiconductor chip by the first pickup unit is being executed, the step of calculating the position of a good semiconductor chip in the second image data is executed. 4. The method of picking up a semiconductor chip according to claim 1, wherein   The number of non-defective semiconductor chips that can be picked up by the pickup means simultaneously with the first and second semiconductor chips in the second image data excluding the first and second semiconductor chips, 5. The method according to claim 1, further comprising a step of calculating an angle and a position based on the second image data before picking up and moving the picked up image to a pickable position. 6. Semiconductor chip pickup method.

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