JPH07111996B2 - Measuring method of lead pin floating of flat package type IC - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a flat package type IC, and in particular, to a package body, usually a QFP in which lead pins are respectively provided in four directions.
(Quad Flat Package) type of flat package type IC (hereinafter simply referred to as flat package type
IC)) lead pin floating measurement method.

[Conventional technology]

The lead pin of the flat package type IC is composed of a portion protruding laterally from the package body, a taper portion obliquely extending from the portion in a direction intersecting with the protruding portion, and a pin end portion extending again in the lateral direction from the taper portion. There are a so-called gull wing type, a J type that wraps around the lower surface of the package body, and the like.

In order to accurately connect the IC package to the substrate, these lead pins must maintain proper positions, directions, and intervals, and those that are out of order must be excluded as defective products.

Taking the gull wing type lead pin as an example, the bend between the root protrusion and the pin end, the pin end floats, the tip is twisted, the pitch is abnormal, the length is uneven or broken, and some of them extend diagonally in the same direction. Abnormalities such as crab legs are possible. Further, a similar abnormality can be considered in the J-type lead pin.

Among these abnormalities, the following is an example of a conventional method for inspecting the floating of the lead pin end.

That is, the flat package type IC to be inspected is arranged on the inspection table having a linear measurement base edge line so that the end portions of the lead pins are parallel or substantially parallel to the measurement base edge line when viewed from above. Of the lead pin end portion and the measurement base edge line with a camera device from the outside of the contact portion in the board mounting, and the floating of each lead pin end portion with respect to the measurement base edge line is measured based on the image. is there.

[Problems to be Solved by the Invention]

However, in order to measure the floating of the lead pin end portion with respect to the measurement base edge line, it is necessary to illuminate both of them at the same time so that they can be clearly photographed. It may be difficult to adjust the position of the light source for that purpose.

Further, as another problem, the measurement base edge line actually has irregularities, and when this is too rough, the measurement results vary and the measurement accuracy decreases.

Therefore, an object of the present invention is to provide a lead pin floating measuring method for a flat package type IC, which can easily illuminate the above-mentioned imaged portion and can further improve the measurement accuracy. is there.

[Means for Solving the Problems]

The method for measuring the lead pin floating of the flat package type IC according to the present invention for solving the above-mentioned technical problem is to measure the flat package type IC in which the lead pin is projected in four directions of the package body in a linear manner. On the inspection table having a base edge line, the end portions of the lead pins are arranged so as to be parallel or substantially parallel to the measurement base edge line when viewed from above, and the outer side of the contact portion of the IC lead pin on the board is mounted. Is a method for measuring the lead pin float of a flat package type IC, in which the lead pin end and the measurement base edge line are photographed by a camera device, and the float of each lead pin end with respect to the measurement base edge line is measured based on the image. Prior to measuring the lift of each lead pin end with respect to the measurement base edge line, The virtual line connecting two points said the measured baseline by specifying two points on the base edge line,
It is characterized in that the floating at the end of each lead pin with respect to the baseline is measured.

[Work]

According to the method of the present invention, for example, the end portions of the lead pins are illuminated so that they illuminate well, and first, two points on the edge line of the measurement base of the inspection table, which are photographed by the camera device, are designated and the measurement bases are connected to each other. After determining the line, it is possible to easily measure the floating of each pin end portion with respect to the virtual baseline.

〔Example〕

Hereinafter, an example of the method of the present invention will be described with reference to the drawings together with an example of an apparatus for carrying out the method.

FIG. 1 shows an IC handler 1 in an IC tester that is already known per se, which inputs a signal to the IC to inspect whether the IC is good or bad, and an image input device 2 detachably attached to the IC handler 1.
An image processing / measuring device 6 connected to the device 2, and the device 6
3 is a side view of a display device (CRT in this example) 7 connected to the printer and a recording device (printer in this example) 8 for recording the inspection result.

FIG. 2 is a plan view of the image input device 2 shown in FIG.

The IC handler 1 is capable of mounting an IC to be inspected on an inspection table 21 described later or receiving an inspected IC from the table.

As a specific example, a tray 1 in which a plurality of flat package type ICs having gull wing type lead pins are mounted side by side
1. Lifting tables 12, 12a, 12b supporting a good IC receiving tray 11a and a bad IC receiving tray 11b, a frame 13 capable of reciprocating horizontal movement in one direction X above the table, and a right angle to the direction X on the frame. Catcher support member 14 that can reciprocate in the horizontal direction Y, vacuum suction holding type provided on the member 14
An IC catcher 15, a rotatable IC support arm 16 arranged outside the table 12b, and a pair of vacuum suction holding type IC catchers 17a, 17b facing the arm 16 are provided. The pair of catchers 17a and 17b are provided at both ends of an arm 171 that is rotatable in a horizontal plane by a driving unit (not shown).

The IC catchers 15, 17a, 17b can be moved up and down by a driving unit (not shown), and are connected to a vacuum suction unit (not shown). The IC support arm 16 is driven to rotate in a horizontal plane by a driving means (not shown), and both ends are
It has IC supporting surfaces 161, 162.

The IC supporting arm 16 is arranged below the arm 171, and the circular movement locus of the IC supporting surface of the arm 16 overlaps with the circular movement locus of the catcher on the 171 at one place.

The support arm 16 is rotated so that one of the support surfaces 161 or 162 can receive and transfer the IC with the catcher 15 and at the same time, the other support surface 162 or 161 can be positioned to transfer the IC with the catcher 17a or 17b. Can move. Further, the arm 171 is provided at a position where one catcher 17a or 17b can deliver the IC to the support surface 161 or 162 of the arm 16, and at the same time, the other catcher 17b or 17a is connected to the inspection table 21 and the IC of the image input device 2 described later. It can be rotated so that it can be placed in a position where it can be handed over.

This handler 1 operates as follows.

Movement of frame 13 in X direction, Y of catcher support member 14
A combination of directional movements allows the catcher on member 14 to
15 moves above the target flat packaged IC to be inspected in the tray 11 on the table 12. Subsequently, the catcher 15 descends, holds the IC by suction, and then ascends.
Subsequently, the IC is placed on one IC support surface 161 on the IC support arm 16 by the catcher 15 by the combined movement of the frame 13 and the support member 14 in the X and Y directions. After that, the catcher 15 moves up to prepare for the next IC transfer.

On the other hand, the arm 16 rotates and the supported IC is placed under one catcher 17a. Thus, the catcher 17a descends, sucks and holds the IC, and ascends. After that, the catcher support arm 171 rotates, and the IC is placed above the inspection table 21. At this point, the catcher 17a descends to place the IC on the inspection table. After that, the catcher 17a rises.

During this time, the next IC is placed from the catcher 15 on the other support surface 162 of the IC support arm 16, and is placed under the other catcher 17b by the rotation of the arm 16 and held by the catcher.

When the inspection of the IC on the inspection table 21 is completed, the catcher 17a
Holds it, and the arm 171 turns. The IC held by the catcher 17b thus faces the inspection table 21, and the next I
C is placed.

The tested IC held by the catcher 17a is the support arm 16
Placed on top, and then held by catcher 15,
It is placed on the good tray 11a or the bad tray 11b.

After that, the catcher 15 supports the next IC to be inspected by the support arm 16
The IC is placed on the empty support surface above, and the IC is held by the catcher 17a to prepare for the next inspection.

By repeating the above operation, the ICs to be inspected are sequentially placed on the inspection table 21, and the inspected ICs are stored in the tray 11a or 11b.

The handler 1 is a commercially available IC tester, and the image input device 2 is attached after removing a tester part (not shown) of the IC tester. There is.

The apparatus 2 includes an inspection stage 20, on which an inspection table 21 is detachably arranged. Examining table
21 is the inspection table 21 when the IC held by the catcher 17a or 17b of the handler 1 is lowered by the catcher 17a or 17b.
It is in a position where it can be placed on top or the IC on the inspection table can be received by the catcher.

As shown in FIG. 3, the inspection table 21 includes a base 211 and IC guide protrusions 212, 213, 214, 215 that are erected at predetermined positions on the base 211.
Is equipped with. The base 211 has a quadrangular shape in plan view, and the upper end surface is a flat measurement base surface 211a.
It has L1 to L4.

The protrusions 212 to 215 are parallel to the edges L1 to L4, respectively, and are formed at the same height. The surface color is entirely black.

By the way, the IC package 10 that has the inspection symmetry is, for example,
As shown in FIGS. 4 and 5, a protruding portion b protruding laterally from the rectangular IC package body a, a tapered portion c extending obliquely from the portion so as to intersect the portion, and the portion c again A plurality of gull-wing type lead pins P each having a pin end portion d extending in the lateral direction are provided on each side of the main body a.

Each of the guide protrusions 212 to 215 of the inspection table is provided with a tapered outer surface (inclined outer surface) F.

The outer surface F of the taper is, as shown by the chain double-dashed line in FIG.
It serves as a guide when mounting and positioning the package 10 on the inspection table.

That is, when the package 10 is placed on the inspection table, the inner surface cs of the tapered portion c of the lead pin P is guided to the outer surface F, and finally the pin end portion d is on the measurement base surface 211a of the inspection table base. Get in place.

FIG. 5 shows a state in which the outer surface F is still in contact with the lead pin inner surface cs even in such a mounted state, but in reality, the pin end portion d is thus mounted on the surface 211a. Then, the pin inner surface cs is separated from each of the one or more outer surfaces F of the guide protrusions.

However, when the pin end portion d rides on the surface 211a, the pin inner surface cs may still be in contact with the outer surface F of the protrusions 212 to 215, but in any case, the lead pin P is supported by the protrusions 212 to 215. Avoid being caught and floating in the air.

Further, the positions of the protrusions 212 to 215 on the surface 211a are determined in advance so that the pin end portion d rides on the surface 211a in this manner.

In the state of being supported in this way, the arrangement direction of the lead pins lined up on each side of the IC is the edge lines L1, L2,
It will be parallel or nearly parallel to L3 or L4. Further, the end surface ds of each lead pin end portion d in each pin row is the inspection table base 211.
Are substantially aligned with the side surfaces S1, S2, S3 or S4.

This IC supporting method is a conventional IC inspection positioning method based on the lower surface m1 or side surface m2 of the synthetic resin molded body M of the IC package body a, or a conventionally known well-known method having a quadrangular recess whose inner peripheral side surface is inclined like a mortar. It is possible to perform more accurate inspection and positioning of the IC as compared with the method of positioning by dropping the IC into the recess of the positioning jig.

This is because the lower surface m1 and the side surface m2 of the molded body M may be deformed or have irregularities due to defective molding, and in the method of dropping the jig M into the concave portion of the jig, there are variations in positioning due to uneven lengths of the IC lead pins. Get out. On the other hand, the projecting portion b of the lead pin P and the taper portion c following the projecting portion b have relatively little variation and are accurately finished.

Although the guide protrusions 212 to 215 are separately provided upright, they may be integrally formed.

Although not used in this example, two guide protrusions having the tapered outer surface F as described above are erected in parallel on the upper surface of the inspection table base 211, and a stopper is provided at a right angle to them.
By positioning the pin on the upper surface of the base by guiding the inner surface cs of the taper portion of the lead pin to the upper surface of the base, the IC is positioned in the front-rear direction or the left-right direction, and then the IC is reached up to the stopper by a pusher or air blowing. The final positioning can also be performed by moving.

It is also conceivable that a table having the above-described guide protrusions on the flat upper surface is provided separately from the inspection table and used as a positioning table. In this case, the taper inner surface cs of the lead pin may be supported by the taper outer surface F of the protrusion to float the lead pin, or may be supported like the inspection table 21.

Now, an inspection mark is attached to the side surface of the base portion 211 of the inspection table 21.

More specifically, the upper end of each of the side surface S1 including the edge line L1 and the side surface S3 including the edge run-in L3 facing the side surface S1 is provided with marks n1, n2, and n3 at predetermined intervals in the direction of the edge line. The side surface S2 including the edge line L2 and the side surface S4 including the edge line L4 facing the side surface S2 are each provided with a mark n4 at the center of the upper end. Each mark is white or metallic in color so that it can be illuminated well by illumination.

The role of these marks will be clarified later.

Returning to FIGS. 1 and 2 again.

A total of four camera devices 31 to 34 are arranged at right angles to each edge line of the inspection table 21.

Each camera device is equipped with an optical system including a lens and a camera, and photographs the lead pin and the inspection frame edge line from the outside of the contact portion (pin end portion d in this example) in mounting the IC lead pin on the inspection table 21 on the substrate. can do.

Each camera device has a guide rail 35 laid on the top surface of the stage 20.
It is possible to reciprocate in the direction of the facing inspection edge line. The rail 35 and various parts such as a motor, which will be described below, form the interlocking mechanism 30 of the camera device.

A motor 36 is provided on the lower surface of the stage 20, and a screw rod 361 that is normally and reversely rotated by the motor 36 is threadedly inserted into a female screw portion 362 on the lower surface of one camera device 31. This female screw portion penetrates the long hole 201 of the stage. Therefore, the camera device 31 is reciprocally driven along the rail 35 by the operation of the motor 36.

A rod 311 extends downward from the female screw portion 362 toward the center of the stage.

On the lower surface of the camera device 32, 33, 34, the stage long holes 202, 2
Sliders 321, 331, 341 extending downward through 03, 204
Are provided, and rods 322, 332, 342 extend downward from the center of the stage. Each slider slides along the guide rod 300.

A disk 37 is rotatably installed on the lower surface of the stage, and pins 381, 382, 383, 384 are installed upright on the upper surface of the disk.
Rods 311, 322, 332, 342 extending from the camera device are in contact with these pins, and tension springs 391, 392, 393, 394 are stretched over the disk 37 and the rods, respectively. The spring pulls the disc 37 so that the pin always contacts the rod.

Therefore, when the camera device 31 is moved in the direction of the arrow T1 in FIG. 3, the rod 311 pushes the pin 381 on the disk, and the rotation of this pin causes the springs 392 to 394 to move the rods 322, 33.
Pull 2,342 to pull the camera device 32,33,34
Move by the same amount as 31 in the directions T2, T3, T4.

When the camera device 31 is returned in the direction opposite to T1, the disc 37 is pulled by the spring 391 and pivots back, whereby the pin 382 is rotated.
When ~ 384 pushes the rods 322 ~ 342, the other camera devices are linked in the opposite direction by the same amount.

The rods 311 to 342 may have a bifurcated shape that sandwiches the pin on the disc 37. Further, when the camera devices 31 to 34 can be supported by the guide rails 35, the sliders 321 to 341 on the lower surface of the camera device, the rod 300 guiding the sliders and the stage slots 202 to 204 through which the sliders pass may be omitted. . Further, the motor 36, the screw rod 361, and the female screw portion 362 may be arranged on the stage 20.

The interlocking mechanism 30 is as described above.

Light source part 4 including halogen lamp in one corner on stage 20
1, 42, 43 and 44 are provided, and the tips of the optical fibers 51, 52, 53 and 54 extending from these light source units are attached to the corresponding camera devices.

According to the image input device 2 described above, each camera device is initially arranged at the initial position by the interlocking mechanism 30. Then, all the lamps of the light source units 41 to 44 are turned on. In this example, these lamps are all turned on during the inspection period in order to avoid early deterioration of the lamp and fluctuation of the light amount due to repeated on / off.

Of the sides of the IC 10 to be inspected placed and positioned on the inspection table 21, the lead pin P on the side toward the first camera 31 is first photographed by the camera device. In this photographing, the optical fiber 51 illuminates the lead pin.

Of the lead pin P group, first, several to several tens including the pin P1 at the extreme end are photographed by the camera device 31 at once. At this time, the inspection mark on the edge line L1 and the side surface S1 of the inspection base
n1 and n2 are also taken at the same time.

The image thus obtained is input to the image processing / measuring device 6 connected to the image input device 2 and displayed on the CRT 7 connected to the device 6. At this time, the screen of CRT7 is as shown in FIG.

As can be seen from this figure, one or more pins P3 etc. after the mark n2, which is not inspected at this point in time, are also photographed at the same time.

When the necessary processing in the image processing / measuring device 6 based on the input image is completed, each camera device remains stationary, and then the lead pin P on the IC side facing the second camera device 32 is the device 32. To be photographed.

At this time, the edge line L2 of the base of the inspection table and the mark n4 on the side surface S2 are photographed together with all the lead pins including the pin P5 on one side of the mark n4. In this photographing, the optical fiber 52 illuminates the lead pin.

The image thus obtained is input to the image processing / measuring device 6 and also displayed on the CRT 7.

At this time, the screen of CRT7 is as shown in FIG. As can be seen from this figure, one or more pins P6 and the like on the opposite side of the mark n4, which is not inspected at this point in time, are also photographed at the same time.

When the necessary processing in the device 6 based on the image thus input is completed, each camera device remains stationary, and then the third camera device 33 causes the camera device to illuminate the optical fiber 53. Part of the lead pin on the IC side facing the device is the first
Similar to the image taken by the camera device 41, the edge line of the base of the inspection table
The image is taken together with the marks n1 and n2 on L3 and the side surface S3, input to the image processing / measuring device 6, and displayed on the CRT 7.

After that, while the respective camera devices remain stationary, the fourth camera device 34 illuminates the optical fiber 54, and a part of the lead pin on the IC side facing the camera device is taken by the second camera device. Similarly, it is photographed together with the inspection table base edge line L4 and the mark n4 on the side surface S4 and input to the device 6,
Displayed on CRT7.

In addition, when shooting the lead pin with each camera device,
Since the guide protrusions other than the guide protrusions of the inspection table on which the lead pins to be imaged are mounted block a part of the light incident from the back of the lead pins, the image capturing becomes easier and more accurate.

Now, when a series of photographing and image input is completed in this way, the camera devices 31 to 34 are operated by the second operation under the operation of the interlocking mechanism 30.
In the figure, it is moved by a certain amount in the directions of arrows T1 to T4.

After that, first, the first camera device 31 faces this.
The remaining lead pins P3 to P4 on the IC side are the edge line L1 and mark
The images are taken together with n2 and n3, input to the image processing / measuring device 6 and displayed on the CRT 7. At this time, the CRT display screen is as shown in FIG.

Subsequently, the remaining portion of the lead pin on the IC side facing the second camera device 32 is photographed together with the edge line 2 and the mark n4, and the image is input to the device 6 and the CRT 7
Is displayed in. At this time, the CRT screen is as shown in FIG.

Further, the third camera device 33 allows the IC to face it.
Lead pin remaining on the side, edge line L3, marks n2, n3 are first
The image is taken in the same manner as the image taken by the camera device, and the image is input to the device 6 and displayed on the CRT 7.

Then, by the fourth camera device 34, the IC facing this
The remaining lead pin on the side, the edge run-in L4, and the mark n4 are photographed in the same manner as the photographing by the second camera device, and the image is input to the device 6 and displayed on the CRT 7.

By the above, the image input of all the lead pins is completed,
After that, the interlocking mechanism 30 returns each camera device to the initial position to prepare for the next inspection.

During the above image input operation, the IC to be inspected 10 remains stationary on the inspection table 21, so there is no IC position shift due to acceleration, vibration, etc. that occurs when moving the inspection table, and accurate lead pin imaging without variations. It is possible to improve the accuracy of the lead pin inspection.

The illumination devices 41 to 44 of the image input device 2 may be replaced with those shown in FIG. The lighting device of FIG. 13 saves power and simplifies the device, and uses one light source unit 40. In the light source unit 40, the above-mentioned four optical fibers 51
~ 54 are all connected. The light source unit 40 is provided with a halogen lamp 401, which is constantly turned on during the inspection period, and the switching device 40A sequentially switches and conducts light to the optical fiber used for optical illumination of the lead pin. Switching device 40A
Is an optical fiber 51 gathered at equal intervals on one virtual circle.
54 to 54, the perforated shutter 402 can be rotated by the motor 404 through the transmission portion 403 at a required angle.
Sequentially face the end face of the optical fiber to make the hole conductive.

Now, in the case of this example, the image processing / measurement device 6 uses the image input from the device 2 for measurement in a multi-valued state. Of course,
The device 6 may be one that binarizes the input image.

In this example, in order to inspect the floating of the pin end portion d of each lead pin P, the image processing / measuring device 6 simultaneously inspects a plurality of lead pins P imaged by each camera device at the same time. Window processing is performed on the basis of the mark for each pin, and for each pin end portion d in the window,
The pin end portion d and the inspection table base edge line L1, L2, L3 thereunder
Alternatively, the distance from L4 is measured, and when the value exceeds a predetermined threshold value, it is determined to be defective, and if it is within the threshold value, it is determined to be a good product, and the handler 1 is instructed accordingly. The measurement result is printed out by the printer 8.

For example, when the image input by the first camera device 31 is as shown in FIG. 6, the positions of the marks n1 and n2 are obtained based on the shape of the marks stored in advance in the device 6, and the marks n1 and n2 are calculated. Based on, the window W1 is applied to the pin P2 starting from the end of the mark n1 to the end of the mark n2.
Float inspection is performed on each pin end portion d in the window.

In this case, the position of each pin end and the measurement reference point at that end (the front edge of the lower surface of the pin end in this example) are determined based on the rectangular end face ds shape of the pin end d stored in advance in the device 6. To be

Further, when the image input by the first camera device 31 is as shown in FIG. 8, the positions of the marks n2 and n3 are obtained, and with reference to the marks, from the pin P3 to the mark n3 starting from the mark n2 side. The window W2 is hung up to the pin P4 in front of, and the floating inspection is performed on each pin end portion in the window.

The image input by the third camera device 33 is similarly processed.

Further, when the image input by the second camera device 32 is as shown in FIG. 7, the position of the mark n4 is obtained, and the pin P5 or the like on one side of the mark n4 is multiplied by the window W3 based on the mark. , Inspect floating for each pin end in the window.

When the image input by the second camera device 32 is as shown in FIG. 9, the position of the mark n4 is determined, and the pin P6 or the like on the opposite side is multiplied by the window W4 on the basis of the mark n4.
Float inspect each pin end in the window.

The image input by the fourth camera device 34 is similarly processed.

When the camera device is moved and a plurality of lead pins are photographed for inspection, in order to ensure that all lead pins are inspected, a part of the lead pins photographed when the camera device is at a certain position is Even if the device is moved to the next position and the second shooting is performed, it is necessary to perform overlapping shooting. However, when shooting is performed in this way, up to which of the lead pins captured by the second shooting has been inspected It becomes unclear whether or not.

However, as in this example, by attaching an inspection mark to the inspection table 21, it is possible to perform an inspection for lead pins within a certain frame based on the mark, so that the same lead pin is used twice. No inspections or omissions will occur.

Further, in this example, since the lead pins are directly mounted on the flat upper surface of the inspection table 21, the edge line on the upper surface of the inspection table can be used as the measurement base edge line. And the inspection table upper surface 211a
Can be considered in the same way as the board surface on which the IC is mounted.

When the IC package is actually arranged on the surface of the substrate, it is considered that the IC is supported by at least three lead pins protruding most downward, and the other pins float from the surface of the substrate. Placing the IC package on the top surface of the inspection table, the state that is substantially the same as this state that can actually occur appears.
The lead pin floating inspection by image processing can be performed more accurately.

By the way, when the measurement base edge line of the inspection table is adopted as the measurement reference, if the unevenness of the edge line is too rough, the inspection accuracy is reduced accordingly.

Further, in order to measure the floating of the lead pin end portion with respect to the measurement base edge line, both the base edge line and the pin end portion need to be illuminated at the same time, but it may be difficult to adjust the position of the light source for that purpose.

To solve this problem, two points on the base edge line may be selected and an imaginary line line connecting the two points may be adopted as the measurement reference.

That is, for example, a CRT imaged by the camera device 31
A case where the screen is the same as that shown in FIG. 6 and shown in FIG. 10 will be explained as a typical example. As described above, first, the window
W1 is provided, and among the lead pins in the window, the pins P1 and P2 at both ends are sequentially directed to the inner pins, and the distance between the adjacent pin ends d, d is searched for between pin ends having a predetermined distance or more, Points Q1 and Q2 on the inspection table base edge line L1 under the pin end portions q1 and q2 are obtained, and a virtual measurement baseline 1 connecting the two points is stored as a measurement reference. The portion is well illuminated, and the pin floating is inspected from the distance between each pin end portion d and this line 1.

By performing processing in this way, the floating inspection becomes more accurate. Obtaining the virtual baseline in this way is convenient not only when dealing with multi-valued images but also when carrying out binarization processing of input images.

When performing this processing, the image processing / measuring device 6 is provided with such a processing function.

The lead pin floating inspection described above can also be applied to the J-shaped lead pin floating inspection.

The image input device 2 can also be used for inspection of bending of IC lead pins. This will be described next.

That is, as described above, since the protruding portion b of the lead pin P and the tapered portion c subsequent thereto are manufactured with a relatively small variation and with high accuracy, a predetermined position and a pin end on the bent portion e where the portions b and c are continuous are formed. A predetermined position on the part d is set as a measurement point, and these measurement points are set by the camera device.
The bend of the lead pin is detected by taking an image with 31, 32, 33 or 34, inputting the image to the image processing / measuring device, and obtaining the distance between the two measurement points by the image processing / measuring device.

As an example, as shown in FIG. 11, the center point R1 of the bent portion e of the lead pin P and the upper edge center point R2 of the pin end face ds are used as measurement points, and these measurement points are shown in the image. Similarly to the case of the lead pin floating inspection, a plurality of lead pins on each side of the IC are sequentially photographed and the image is processed by the image processing / measuring device 6
In the device 6, the distance between the two points is sequentially measured for each lead pin, and when the measured value exceeds a predetermined threshold value, it is determined as a defective IC, and when it is within the threshold value, it is a non-defective IC.
And The handler 1 is notified of the goodness and the badness.

The image taken by the camera device is displayed on the CRT 7, and the calculation result is printed out by the printer 8.

In this inspection, each camera device has a deep focal depth so that both measurement points can be imaged at the same time.
Further, of course, the image processing / measuring device 6 is provided with a function capable of performing the above processing.

In the conventional lead pin bending inspection, two camera devices are required to photograph from above, for example, the measurement point b1 on the protruding portion b of the lead pin and the measurement point d1 on the pin end portion d shown in FIG. Since one camera device is sufficient, the image input device can be made smaller and simpler and can be provided at low cost.

Of course, in order to be used for the lead pin bending inspection, a pair of camera devices can be replaced with each of the camera devices 31 to 34 of the image input device 2 as in the conventional case.

In addition, as a method of simultaneously photographing two measurement points on the IC lead pin P for the bend inspection, as shown in FIG. 12, the line f is set up at the center g on the line f connecting the points b1 and d1. It is conceivable that one camera device CA having a deep focal depth is arranged on the perpendicular line h, and the points b1 and d1 are simultaneously imaged by this camera device CA. It is also possible to replace each of the camera devices 31 to 34 in the image input device 2 with the camera device CA having such an inclined arrangement in order to be used for the lead pin bending inspection.

〔The invention's effect〕

According to the method of the present invention, as described above, two points on the photographed measurement base edge line are designated and the two points are connected to each other before the floating of each lead pin end portion with respect to the measurement base edge line is measured. The virtual line is the measurement baseline,
Since the float of each lead pin end portion with respect to the baseline is measured, it is possible to easily illuminate the part to be photographed and improve the measurement accuracy as compared with the conventional measurement method described above. It is possible to provide a method of measuring the lead pin floating of a flat package type IC, which has an excellent practical effect.

[Brief description of drawings]

The drawings are for explaining an embodiment of the present invention, and FIG. 1 is an IC handler, an image input device, an image processing / measuring device,
FIG. 2 is a plan view of the image input device, FIG. 3 is a perspective view of an inspection table, FIG. 4 is a plan view of a flat package type IC, and FIG. 5 is the same IC. 1 to 6 are side views, and FIGS. 6 to 9 are views showing an example of a display (CRT) screen by IC package photographing of a camera device, respectively.
Fig. 0 is a diagram showing how to determine a virtual measurement baseline, Fig. 11 is an explanatory diagram of a lead pin bending inspection, Fig. 12 is an explanatory diagram of another example of the lead pin bending inspection, and Fig. 13 is a schematic of another example of a lighting device. It is a perspective view. 1 …… IC handler 2 …… Image input device 21 …… Inspection table 211 …… Inspection table base 211a …… Base upper surface 212 to 215 …… Guide projection F F …… Guide projection tapered outer surface S1 to S4 …… Base side L1 to L4 …… Measuring base edge line n1 to n4 …… Inspection mark 20 …… Inspection stage 201 to 204 …… Stage long hole 31 to 34 …… Camera device 41 to 44 …… Light source section 51 to 54 …… Light Fiber 30 …… Interlocking mechanism 321,331,341 …… Slider 322,332,342 …… Rod 381… 384 …… Pins 391-394 …… Spring 37 …… Disc 35 …… Guide rail 36 …… Motor 361… … Screw rod 362 …… Female thread part 300 …… Guide rod 6 …… Image processing / measuring device 7 …… CRT 8 …… Printer W1 to W4 …… Window q1, q2 …… Pin end gap Q1, Q2 …… Point on measurement base edge line q …… Virtual measurement baseline 10 …… IC package P …… Lead pins P1 to P6 …… Lead pins M: Synthetic resin molded body a: IC package body b: Projection part c: Tapered part cs: Tapered part inner surface d: Pin end part ds: Pin end part end surface e: Bent part R1, R2 ... Lead pin bending measurement point CA ... Camera device b1 ... Measurement point on protruding part b1 ... Measurement point on pin end d f ... Line connecting b1 and d1 g ... between b1 and d1 Mid-point h ... perpendicular to line f ... illumination device 40A ... switching device 401 ... light source 402 ... shutter 402a ... hole 403 ... transmission unit 404 ... motor

Claims (1)

[Claims] 1. A flat package type IC to be inspected having lead pins projecting in four directions of a package body is mounted on an inspection table having a linear measurement base edge line, and the end portions of the lead pins are seen from above. Arranged to be parallel or substantially parallel to the measurement base edge line, the lead pin end portion and the measurement base edge line are photographed by a camera device from the outside of the contact portion in the board mounting of the lead pin of the IC, A method for measuring the lead pin floating of a flat package type IC for measuring the floating of each lead pin end with respect to the measurement base edge line based on an image, prior to measuring the floating of each lead pin end with respect to the measurement base edge line, By designating two points on the imaged measurement base edge line and setting a virtual line connecting the two points as a measurement baseline, Lead pins floating measuring method of a flat package type IC, which comprises measuring the floating of the lead pin end with respect to the line.