JPH03257936A - Pick-up equipment for semiconductor chip - Google Patents

Abstract

PURPOSE:To facilitate the adjusting work in the case of replacing work of a vacuum sucking collet for a collet holder, by mounting the collet holder on a retainer driven up and down by a driving motor for control use so as to be capable of freely sliding up and down, and providing a sensor to detect the height position of the collet holder. CONSTITUTION:When a vacuum sucking collet 13 is replaced for a collet holder 14, the height position of the collet holder 14 for a retainer 11 is detected with a sensor 26 fixed on the retainer 11. It is discriminated whether the collet holder 14 has ascended by a specified amount ( L) from a stopper 19, with reference to a sensor 26 fixed at a reference position; the deviation of the height position before and after the vacuum sucking collet 13 is exchanged for the collet holder 14 is calculated; the elevating amount of the retainer 11 is determined by setting the above calculated result as a correction value. It is also possible that detection is not always executed by the sensor, by performing one time study at the time of exchanging the vacuum collet 13.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention is directed to a vacuum suction collet for picking up semiconductor chips in a semiconductor device such as a semiconductor integrated circuit device (IC, LSI, etc.) from a place such as a wafer sheet or a chip tray. The present invention relates to the structure of a pickup device used for picking up a semiconductor chip and transporting it for die bonding onto the top surface of a lead frame or to a table for correcting the posture of a semiconductor chip.

[Conventional technical background]

This type of pickup device is disclosed in the prior art, for example, Japanese Utility Model Application Publication No. 57-110943.
A vacuum suction collet (with a suction passage opening at the bottom end surface) is attached to a collet holder that moves horizontally and vertically, and the vacuum suction collet and collet holder are attached to a semiconductor chip on a wafer sheet or chip tray on a workbench. The collet holder is lowered together to pick up the semiconductor chip while it is vacuum-adsorbed on the cylindrical lower end surface of the vacuum adsorption collet, and then the collet holder is moved laterally and lowered towards the lead frame, etc. on the workbench where die bonding is to be performed. Then, the vacuum suction of the vacuum suction collet is turned off and set at a predetermined position on the lead frame or the like.

[Prior Art and Problems to be Solved by the Invention] Data such as the distance and timing for vertically and horizontally moving the collet holder equipped with a vacuum suction collet in this pickup device are inputted in advance into the storage section of a computer. Based on the data, a stepping motor, which is a control drive motor, is pulse-controlled to move the vacuum suction collet vertically or horizontally by a predetermined distance.

For example, in the pick-up process from the chip tray, the vertical movement distance of the collet holder is based on the distance from the lower end of the vacuum suction collet at the raised position of the collet holder to the top surface of the semiconductor chip on the chip tray on the workbench. The collet holder is moved up and down by the distance.

By the way, it is necessary to replace the vacuum suction collet due to changes in the size of the semiconductor chip to be vacuum suctioned, or wear of the vacuum suction collet, etc. In this case, the vacuum suction collet must be replaced with the collet holder. work must be performed.

During replacement work, for example, if the vacuum suction collet is installed at a position that is offset from the standard height position of the collet holder so that the amount of downward protrusion becomes large, the attachment will be less than the vertical movement distance of the collet holder before replacement. If the stepping motor is lowered by driving the predetermined number of pulses with the same data, the amount of descent of the collet holder will be too large, and the lower end of the vacuum suction collet will collide with the semiconductor chip on the workbench with a strong impact. Accidents may occur in which the suction collet or semiconductor chip is damaged.

On the other hand, if the vacuum suction collet is installed at a higher position than the collet holder, an extra gap will be created between the lower end surface of the vacuum suction collet and the top surface of the semiconductor chip at the lower limit of the collet holder. When a semiconductor chip is placed by lowering it with respect to the top, etc., the semiconductor chip falls freely due to the above-mentioned gap, causing problems such as displacement of the installation position of the semiconductor chip.

In order to avoid these inconveniences, in the conventional technology, when attaching or replacing the vacuum suction collet, as shown in FIG. On the other hand, when the collet holder 3 is lowered by a predetermined amount based on data stored in the computer, the height from the lower surface of the collet holder 3 to the workbench 1 becomes the reference height (Hl).

Next, the vacuum suction collet 4 is replaced at the lowered position. In this case, it is necessary to fix the new vacuum suction collet 4 to the collet holder 3 with the lower end surface of the new vacuum suction collet 4 in tight contact with the upper surface of the jig 2. However, if the dimensions of this installation are out of order, the above-mentioned inconvenience will occur, and the adjustment is extremely troublesome.

Further, as shown in FIG. 9, the outer diameter of the cylindrical vacuum suction collet 5 is formed to be different in size in the middle of the cylinder axis. ), it is possible that the stepped part 6 is fixed in a state where it is in tight contact with the lower end surface of the collet holder 3, etc., but in this case, the vacuum suction collet 5 has a special step called the step. There was a problem in that it required processing, which increased manufacturing costs.

The present invention aims to solve these problems.

[Means to solve the problem]

In order to achieve this object, the present invention attaches a collet holder to a support body that is moved up and down by a control drive motor so as to be able to slide in the vertical direction, urges the collet holder downward, and uses its lower limit as a stopper. A vacuum suction collet for vacuum suctioning a semiconductor chip is detachably attached to the collet holder, and a sensor is provided on the support body to detect the height position of the collet holder. , the amount of lifting and lowering of the support body by the control drive motor is corrected based on the detection signal from the sensor.

[Operation and effect of the invention]

According to this configuration, the vacuum suction collet is detachably attached to the collet holder, the collet holder is attached to the support body so as to be slidable up and down, and the collet holder is biased downward, and furthermore, the collet holder is lowered. Since the lower limit is regulated by a stopper, during the lifting and lowering of the support,
In particular, unless the lower end surface of the vacuum suction collet collides with another object such as a semiconductor chip while descending, the collet holder will remain in contact with the stopper and held at the lowest position relative to the support. and the vacuum suction collet move up and down together with the support.

When the lower end of the vacuum suction collet comes into contact with a semiconductor chip or the like when the support is lowered, the collet holder together with the vacuum suction collet rises with respect to the support against the downward biasing force. That is, the collet holder rises away from the stopper on the support.

On the other hand, the sensor provided on the support body detects the height position of the collet holder with respect to the support body,
It detects when the collet holder has moved up a certain amount away from the stopper and issues a detection signal, so when installing the vacuum suction collet to the collet holder, the amount of height deviation can be determined before and after replacing the old and new vacuum suction collets. Since this corresponds to the difference in the descending distance of the support body, the correct amount of elevation of the support body can be obtained by simply correcting the difference and moving the support body up and down.

As described above, according to the present invention, there is no need for adjustment work that requires skill when replacing the vacuum suction collet to the collet holder, making the work extremely simple and reducing the work time. be effective.

Furthermore, since there is no need to perform any special processing on the vacuum suction collet or the like, it also has the effect of leading to cost reduction.

〔Example〕

Next, an embodiment will be described. In FIG. 1 showing a schematic diagram of a pickup device, reference numeral 10 denotes a main body part that supports a support body 11 having an angular shape when viewed from the side, and is attached to a reader body part 10. A collet holder 1 drives a support 11 up and down through a control drive motor 12 such as a stepping motor and a transmission part such as a rack and pinion (not shown), and a vacuum suction collet 13 is removably attached to the support 11.
4 is attached so that it can be moved up and down.

This configuration will be described in detail with reference to FIGS. 2 to 4. A vertically elongated slider block 15 is fixed to the bifurcated tip portion 11a of the support 11 with pins 16, bolts 17, etc. A collet holder 14 having a cross-shaped shape when viewed from the side is mounted on the front surface of the slider block 15 so as to be vertically slidable. Reference numeral 18 designates a sliding member attached to the collet holder 14.

Further, reference numeral 19 denotes a stopper fixed to the lower end of the slider block 15, which prevents the collet holder 14 from descending below the 19th stop.

Reference numeral 20 denotes a pair of left and right springs that urge the collet holder 14 downward, and the upper ends of each spring 20 are locked to locking pins 21 that protrude left and right from the collet holder 14.
The lower end of the spring 20 is locked to an L-shaped mounting plate 22, 22 protruding from the support body 11.

The tip of the collet holder 14 communicates with the groove 23.The upper and lower parts of the collet holder 14 are installed by removably fitting the vacuum suction collet 13 into the hole 24, and fixing the position by tightening the groove 23 with a bolt 25. be.

Reference numeral 26 denotes a sensor fixed to the upper end of the slider block 15, and the tip (detection part) of the sensor 26 is placed close to a reference part 27 such as the upper end of the collet holder 14. A non-contact type magnetic sensor such as a resistive type sensor uses a non-contact type sensor that uses the capacitance of a metal, or an optical sensor that detects the position based on the amount of laser light cut off. Contact sensors such as differential transformers or linear potentiometers may also be used.

Then, it is set so that a detection signal (ON) is output when the upper end of the reference part 27 is located at the detection height position 26a (for example, the center line) of the sensor 26, and the vertical length (H3) is set.
When the collet holder 14 is in contact with the stopper 19, the upper end of the reference part 27 and the detection height position 26
Leave a vertical distance (ΔL) from a. In this case, the sensor 26 may be provided so that the inspection part faces downward and faces the reference part 27.

Further, a controller 28 such as a microcomputer, which is a control means, receives the detection signal from the sensor 26, performs a predetermined calculation, etc., and outputs a necessary number of pulse signals.
The control drive motor 12 is driven by a predetermined amount to move the collet holder 14 up and down the required distance.
For example, as shown in FIG. 5, a semiconductor chip is picked up from the chip tray 30 on the upper surface of the supplying workbench 29, the vacuum suction collet 13 is raised along path A, and then moved laterally through path B. In order to place the semiconductor chip on the lead frame 32 on the upper surface of the workbench 31, it descends along path C, and after placing the semiconductor chip, rises along the path.
It repeats the reciprocating movement of moving laterally on route E and descending on route F.

Note that the amount of elevation on routes A and F is (Ll), and the amount of elevation on routes C and D is (L2).

Next, the control by the controller 28 will be explained according to the flowcharts of FIGS. 6 and 7.

First, in step Sl following the start and initial value setting in FIG. 6, a subroutine for correcting the height position of the vacuum suction collet 13 as shown in the flowchart shown in FIG. 7 is executed, and the resulting correction value (Zo) is executed in step S2. It is calculated and stored, and then in step S3, based on the correction value (ZO), the amount of movement (Ll), (Ll), (
L2) is calculated and stored, and based on this data, a predetermined pulse signal is given to execute control for driving the control drive motor 12 in forward and reverse directions in a predetermined order and at a predetermined timing (step 34). .

In this case, for example, the old vacuum suction collet 1 before replacement
3, the installation from the lower end surface to the lower surface of the tip of the collet holder 14 is assumed to be installed at the height dimension (H2),
At this time, when the support body 11 is set at the upper limit position and the height dimension (Lo) is set from the upper surface of the chip tray 30 on the workbench 29, the semiconductor chip, etc., to the lower end of the vacuum suction collet 13, Actual lifting amount (Ll) of the support 11
=Lo+ΔL) (see Figure 2).

The controller 2 sends a number of pulse signals corresponding to the amount of elevation.
8 and drive the control drive motor 12, it is possible to control the elevation on routes A and F, and in the same way, on routes C and F.
The amount of elevation (L2) at D can also be calculated to control elevation.

To briefly explain the correction control when the vacuum suction cholera 13 is replaced with respect to the collet holder 14, the sensor 26 provided on the support 11 detects the height position of the collet holder 14 with respect to the support 11. This device can determine whether or not the collet holder 14 has moved away from the stopper 19 and has risen by a certain amount (ΔL) with respect to the sensor 26 fixed at the reference position. When the suction collet 13 is replaced, the difference in the height position before and after the replacement is calculated, and this is used as a correction value to determine the amount of elevation of the support 11. One example is the vacuum suction collet 1.
By learning only once when replacing 3, detection by the sensor is not performed constantly.

First, an operator removes the old vacuum suction collet from the collet holder 14 and fixes a new vacuum suction collet 13 thereon.

In this case, when the new vacuum suction collet 13 is installed, the height dimension (H2) is larger than the old one by ΔH, in other words, when the vacuum suction collet 13 is installed downward by ΔH, the support 11 is raised Amount Ll=Lo+ΔL
-ΔH, and if the drive amount of the control drive motor 12 is reduced by an amount corresponding to this ΔH, the lower end surface of the new vacuum suction collet 13 will be tightly attached to the contact area at the lowering limit of the support 11. It is possible to come into contact with it.

On the other hand, when the new vacuum suction collet 13 is installed deviated upward by ΔH compared to the old one, the lifting amount of the support 11 should be set to (L1=Lo+ΔL+ΔH).

Therefore, following the start of the flowchart in FIG. 7, in step PI, the control drive motor 12 is returned to its origin (
T is set to O), and in step P2, a pulse counter that counts the number of pulses (i) applied to the control drive motor 12 is cleared (i is set to 0).

Next, a signal is applied one pulse at a time using a manual switch or the like to operate the control drive motor 12, and the support 11 is lowered. For example, the support body 11 is 0.1 m for l pulse signal.
It is assumed that the object moves by m.

In step P3, the upper end of the reference part 27 in the collet holder 14 is at the detection height position 26a (
For example, it is determined whether or not the object is located on the center line.

When the sensor 26 is not ON (no determination is made in step P3), the lower end surface of the vacuum suction collet 13 is not in contact with the contact portion such as the chip tray 30, so that l is further removed in step P4. The control drive motor 12 is operated to move down a predetermined distance by outputting a pulse signal, and the pulse counter increments the number of pulses by 1 (step P5).

In this way, the operations of step P4 and step P5 are repeated until a YES determination is made in step P3.

If YES in step P3, vacuum suction collet 1
The lower end surface of the collet holder 3 comes into contact with the contacted portion such as the chip tray 30, and in this state, the collet holder 14 separates from the stopper 19 and rises by (ΔL), and the collet holder 1
The upper end of the reference portion 27 at 4 is located at the detection height position 26a (for example, the center line) of the sensor 26.

Number of pulses (i) in the pulse counter in this state
The data is set (step P6), and the data is stored in the controller 2B (step P7).

This pulse number (i) data is based on the vacuum suction collet 13
This corresponds to the predetermined lifting amount of the support 11 after replacing the new one, and the number of pulses for the support 11 in the case of the old vacuum adsorption collet 13 before that
For example, when the difference is greater (less) by the number of Δi pulses, the comparison calculation is made with the data in i). 4) The old vacuum suction collet is installed in a higher position than the new vacuum suction collet 13 is installed in a higher (lower) position. In step S2, the correction value (Z o
) are calculated and stored, and the routes A, F and C are calculated and stored.
, D, the amount of movement (Ll) and (L2) of the vacuum suction collet 13 in the height (vertical) direction is calculated, and the number of pulse signals used to drive the control drive motor 12 is reduced (added). It is sufficient to operate it in the state).

In addition, as can be understood from the above explanation, the vacuum suction collet 13 after replacing the collet holder 14
The height deviation (ΔH) corresponds to the difference (Δi) between the number of pulses (i) in the old case and the number of pulses (i) in the new case. It is not necessary to start from the upper limit position, but it can be started from any height, so the time loss associated with the correction work can be reduced.

In addition, the detection by the sensor 26 is
If so-called learning control is performed, in which the sensor 26 is activated only when replacing item 3 and correction is performed, the reference portion 27 such as the upper end of the collet holder 14 is detected by the sensor 26 that is activated all the time.
is detected, and based on this judgment, the control drive motor 12 is set to 0N-
Compared to OFF control, the occurrence of control failures due to failure of the sensor 26 can be extremely reduced.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the device, Fig. 2 is a side sectional view of the section requiring visual inspection in Fig. 3, Fig. 3 is a plan view, Fig. 4 is a front view, Fig. 5 is a process explanatory diagram, Figures 6 and 7 are flowcharts, Figure 8
The figure is a side sectional view of a conventional technique, and FIG. 9 is a side sectional view of another conventional technique. 1.29.31...Workbench, 2...Jig, 3.
14... Collet, holder 4.5.13...
・Vacuum suction collet, 6...Stepped part, 10...
- Main body, 11...Support body, 12...Control drive motor, 15...Slider block, 19...
・Stopper, 20...Spring, 26...Sensor 27...Reference part, 28...Controller, 3
0... Chip tray.

Claims (1)

[Claims] (1). A support body that moves up and down by a control drive motor,
A collet holder is mounted so as to be slidable in the vertical direction, and the collet holder is biased downward and its lower limit is regulated by a stopper. A suction collet is detachably attached, a sensor is provided on the support body to detect the height position of the collet holder, and the amount of elevation of the support body by the control drive motor is corrected based on a detection signal from the sensor. A pickup device for semiconductor chips characterized by the following.