JPH07287046A - Ic characteristic measurement method - Google Patents

Abstract

PURPOSE:To provide a method for measuring IC characteristics which can increase the efficiency for measuring IC characteristics. CONSTITUTION:A device under test is supplied to a plurality of sockets 5 for measuring IC for activating a pusher 7. Then, an insulation continuity check is performed for the device to be measured, thus judging whether the device under test with a poor insulation continuity exists or not. When the device under test which is judged to be in insulation continuity failure exists, the pusher 7 corresponding to the device under test is activated again, thus moving to a functional test for the device under test.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring characteristics of an IC (semiconductor integrated circuit) which is a device to be measured by using an IC characteristic measuring apparatus having a function of simultaneously measuring a plurality of devices to be measured. It is a thing.

[0002]

2. Description of the Related Art Generally, a characteristic measurement for device evaluation is performed on an IC manufactured into a product after a series of assembling steps. And as an apparatus for measuring IC characteristics,
Some have a so-called simultaneous measurement function (also called a parallel measurement function) for simultaneously evaluating two or more devices under measurement. In this method, the device under test is pressed against a plurality of IC measurement sockets by the operation of a pusher, and the contact point of the IC measurement socket and the external lead of the device under test are brought into contact with each other to perform characteristic measurement. is there

[0003]

By the way, this kind of I
In the C characteristic measuring device, when the device under test is pressed against the IC measuring socket by the operation of the pusher,
Mechanical positioning accuracy of the device under test with respect to the IC measurement socket, and foreign matter (dust etc.) to the connection part of both
Although the device under test is a good product due to adhesion or the like, a good connection state cannot be obtained between the probe of the IC measurement socket and the external lead of the device under test,
In some cases, it was judged as wrong (misidentified) during the continuity insulation check. In such a case, the conventional IC characteristic measuring method is
A function test was performed except for the device under test determined to be defective, or after the characteristic measurement was completed, the device under test determined to be defective in insulation conduction was again put into the IC characteristic measuring apparatus to deal with the problem. For this reason, not only the operating rate for simultaneous measurement is lowered, but also extra man-hours are required for re-measurement.

The present invention has been made to solve the above problems, and an object thereof is to improve the efficiency in IC characteristic measurement.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and a device to be measured is pressed against a plurality of IC measuring sockets by the operation of a pusher to provide a probe for the IC measuring sockets. In an IC characteristic measuring device for measuring characteristics by making contact with external leads of a device under test, the device under test is supplied to a plurality of IC measurement sockets and a pusher is operated, and then insulation conduction for the device under test is conducted. A check is performed to determine whether or not there is a device under test with defective insulation continuity. At this time, if there is a device under test that has been determined to have poor insulation continuity, the pusher corresponding to the device under test is restarted, and then a functional test is performed for the device under test.

[0006]

According to the IC characteristic measuring method of the present invention, the positioning accuracy and connection of the device to be measured with respect to the IC measurement socket are adjusted by reactivating the pusher corresponding to the device to be measured which is determined to be defective during the insulation continuity check. Connection mistakes caused by foreign matter adhering to parts are eliminated.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic diagram showing a configuration example of an IC characteristic measuring apparatus having a simultaneous measurement function (parallel measurement function). In FIG. 1, 1 is a magazine, 2 is a distributor, 3 is a storage track, 4 is a transfer, 5 is an IC measuring socket, 6 is a test head,
7 is a pusher and 8 is an IC tester. A specified number of ICs (semiconductor integrated circuits) 9 that are devices to be measured are stored in one magazine 1, and ICs 9 from the magazine 1 are individually stored in each storage track 3 by a distributor 2. To be distributed.
Further, the ICs 9 taken into the storage track 3 are supplied to the IC measuring sockets 5 via the transfer 4, respectively, and are pressed against the IC measuring sockets 5 by the operation of the pusher 7 there. The test head 6 is provided with a sample power source to be applied to the device under test, a timing generator output, a pattern generator output section, and an input section for taking in the device output, which is electrically connected to the IC tester 8. Has been done. By the way,
When it is necessary to change the temperature of the IC 9 during high temperature measurement or low temperature measurement, the IC 9 waits until a predetermined temperature condition is obtained when the IC 9 is distributed to the storage track 3.

Next, the IC characteristic measuring method according to the present invention will be described with reference to the flowchart of FIG. First, in step S1, a prescribed number (8 in the case of the example) of the ICs 9 distributed by the distributor 2 to the storage tracks 3 are supplied to the IC measurement sockets 5 via the transfer 4. Next, in step S2, all the pushers 9 are actuated simultaneously to press the individual ICs 9 against the IC measurement sockets 5. As a result, the external lead (not shown) of the IC 9 which is the device to be measured is connected to the probe (not shown) on the IC measuring socket 5 side.

Subsequently, in step S3, an insulation conduction (open / short) check is performed on the IC 9 mounted in the IC measurement socket 5, and in step S4, insulation conduction failure is found as a result of the insulation conduction check. It is determined whether or not there is IC9. Here, if all the ICs 9 that have been subjected to the insulation continuity check are determined to be non-defective, the process proceeds directly to step S5, and if there is even one IC9 that is determined to be defective in insulation continuity, the process proceeds to step S6.

In step S6, the number A of failure determinations (the number of times it is determined that there is a defective IC in step S4) A counted by, for example, a counter of the device control system is incremented by 1 (+).
1) Do. Since the number of failure determinations A is set to 0 (zero) at the start of simultaneous measurement, the number of failure determinations A becomes 1 in this step S6. Next, in step S7, it is determined whether the defect determination number A has reached the specified number B. Here, the “specified number of times B” is a number of times set in advance by the operator, and this number of times is the number of ICs that can be simultaneously measured, the time required for the functional test, and the positioning accuracy and connection of the mechanical IC 9. It is set as appropriate in consideration of the frequency of occurrence of connection errors due to the adhesion of foreign matter to the portion. In this embodiment, the case where the prescribed number B is set to 2 will be described.

In step S7, the number of defects detected A
Since (= 1) has not reached the specified number B (= 2), the process proceeds to step S8, where the position information of the defective IC is held. That is, in step S8, the above step S4
Which IC measurement socket 5 the IC 9 determined to have poor insulation continuity is attached to is stored as position information in, for example, a memory of the device control system.

Succeedingly, in a step S9, it is determined that the insulation conduction is defective based on the previously held position information.
Reactivate the pusher 7 corresponding to C9. As a result, the IC 9 which has been determined to have poor insulation continuity is once released from the pressed state by the pusher 7 and then pressed again to the IC measurement socket 5 by the pusher 7.
According to the results of experiments conducted by the present inventor, although the IC 9 was originally a good product, the IC 9 was determined to have poor insulation conduction due to mechanical positioning accuracy with respect to the IC measurement socket 5 and foreign matter adhered to the connection portion. It has been proved that most of them are brought into good contact with the IC measuring socket 5 by the re-operation.

Then, the process returns from step S9 to step S3, and the same operation as described above is repeated. Then, in step S4 subsequent to this, if the IC 9 initially determined to be defective in insulation conduction is properly connected to the IC measurement socket 5 by the subsequent re-operation of the pusher 7, there is a defect I.
It is determined that there is no C, and the process directly proceeds to step S5.

On the other hand, in the case of the IC 9 which is originally determined to be defective due to defective insulation and conduction, there is no effect even if the pusher 7 is re-activated, so that the step S
In 4, it is again determined that there is a defective IC, and the process proceeds to step S6. Then, in step S6, the number of failure determinations A is 1
It is incremented, and the defect determination number A becomes 2 at this point. Therefore, in the next step S7, it is determined that the number of failure determinations A (= 2) has reached the specified number of times B (= 2), the process proceeds to step S10, and the number of failure determinations A is reset to zero (A → 0). After that, the process proceeds to step S5.

In step S5, various functional tests are performed on the IC9 which is the device under test, and in the final step S6, non-defective products and defective products are classified based on the results of the IC characteristic measurement. After that, from storage track 3 to IC
A specified number of ICs 9 are sequentially supplied to the measurement socket 5,
The characteristics of the IC 9 are measured according to the same procedure as above.

In the above embodiment, step S
The specified number B of 7 is set to 2 times and the pusher 7 is re-operated only once. The reason is that the re-operation of the pusher 7 causes the IC measurement sockets 5 and I
This is because there is an extremely high probability that a contact error with C9 will be resolved. However, the present invention is not limited to the above-mentioned number of times, and as described above, the IC capable of simultaneous measurement is used.
Set the number of re-operations of the pusher 7 to 2 or more in consideration of the number of pieces, the time required for the function test, the positioning accuracy of the mechanical device under test, and the frequency of connection errors due to foreign matter adhering to the connection part. You may. Incidentally, even when the number of re-operations of the pusher 7 is set to 2 or more, considering that the operation time of the pusher 7 is minute compared with the time required for the functional test in step S5, the IC characteristics are particularly small. It does not hinder the efficiency improvement in measurement.

[0017]

As described above, according to the IC characteristic measuring method of the present invention, the insulation continuity check is performed on the device under test to determine whether there is a device under test with defective insulation continuity, and the insulation continuity is determined. If there is a device under test that has been determined to be defective, restart the pusher corresponding to that device to connect the device due to the positioning accuracy of the device under test with respect to the IC measurement socket and the adhesion of foreign matter to the connection part. For the device under test in which the error was eliminated and the device under test was a good product, a good connection was not obtained between the probe of the IC measurement socket and the external lead of the device under test. Most of the items will be judged as non-defective. As a result, it is possible to prevent a decrease in the operation rate at the time of a functional test due to the connection mistake, and to drastically reduce the connection mistake of the device under test to the IC measurement socket, thereby saving extra labor for remeasurement. Therefore, the efficiency in IC characteristic measurement can be improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration example of an IC characteristic measuring device.

FIG. 2 is a flowchart showing an embodiment of an IC characteristic measuring method according to the present invention.

[Explanation of symbols]

 5 IC measurement socket 7 Pusher 9 IC

Claims (1)

[Claims] 1. An IC characteristic in which a device under test is pressed against a plurality of IC measuring sockets by the operation of a pusher, and a probe of the IC measuring socket and an external lead of the device under test are brought into contact with each other to perform a characteristic measurement. In the measuring apparatus, first, each device to be measured is supplied to each of the plurality of IC measurement sockets to activate the pusher, and then the insulation continuity check is performed on the device to be measured to see if there is a device to be measured with insulation conduction failure. It is determined whether or not there is a device under test determined to be defective insulation conduction, the pusher corresponding to the device under test is re-activated, and subsequently, a functional test for the device under test is performed. IC characteristic measuring method.