JPH11258299A - Inspection device for semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To select as a defective product if the measurement terminal of an inspection device for a semiconductor device is not in contact with the electrode of the semiconductor device. SOLUTION: A minute current detector A is provided with a detection means 11 for detecting the peak value P1 of a charge current IRc made to flow when bringing the measurement terminal into contact between the electrodes of the semiconductor, a comparison means 12 for comparing the peak value P1 detected by the detection means 11 with a reference current value (a) set beforehand and a judgment means 13 for judging as the defective product if the value obtained by comparing them by the comparison means 12 is equal to or less than the reference current value (a).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device inspection apparatus, and more particularly to a semiconductor element inspection apparatus in which a semiconductor element having a non-contact measuring terminal is selected as a defective product.

[0002]

2. Description of the Related Art A conventional semiconductor device inspection apparatus of this type is schematically shown in FIG. This inspection device 1 has a diode D
To check the reverse current IR flowing when the reverse voltage V is applied. The diode D, which is the device under test, is transported by the transport device (not shown) to the positions of the measurement terminals 2A and 2B and temporarily stopped. After this stop, measurement terminal 2
A and 2B contact both electrodes of the diode D, and the switch S
Is closed, and a predetermined DC voltage is applied to the diode D. FIG. 7 shows a current waveform immediately after the DC voltage is applied.

In FIG. 7, the horizontal axis represents time (t), and the vertical axis represents reverse current (IR). Diode D
Immediately after the DC voltage is applied, a steep charging current IRc having a peak value P1 flows as shown in the figure to charge the stray capacitance of the wiring and the like of the inspection device 1 and the capacitance of the diode D itself. Thereafter, a reverse current IRg, which is a characteristic of the diode D itself, flows. If the reverse current IRg is less than a predetermined value, it is stored as a non-defective product, and if the reverse current is more than the predetermined value, it is stored as a defective product by the storage unit of the inspection apparatus 1. When the measurement time (t) elapses, the switch S is opened to end the inspection, and the transport device transfers the diode D to the next inspection stage. The diode D stored as a defective product during the transfer is discharged from the transfer device.

If the electrodes of the diode D do not come into contact with the electrodes of the diode D due to incomplete or any state of the measurement terminals 2A and 2B of the inspection apparatus 1, even if the switch S is closed, as shown in FIG. Since no current flows, the charging current IRc and the reverse current IRg are small. In this case, the diode is determined to be non-defective, and the true evaluation is unknown. In FIG. 8, IRc is a current for charging the stray capacitance of the wiring, and is a relatively small value.
Is shown.

[0005]

By the way, in the semiconductor device inspection apparatus as described above, the measuring terminal 2 of the inspection apparatus is used.
Even when A and 2B are not in contact with the electrodes of the device to be inspected such as the diode D, the reverse current is lower than the reference level, so that they are determined to be non-defective and there is a problem to be solved in terms of inspection accuracy.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and when a measuring terminal of a semiconductor device inspection device is not in contact with an electrode of a semiconductor device, it is selected as a defective product. It is an object of the present invention to provide a semiconductor device inspection apparatus capable of improving the inspection accuracy.

[0007]

A semiconductor device inspection apparatus according to the present invention applies a voltage between electrodes of a semiconductor device, detects a current flowing through the semiconductor device, and determines the quality of the semiconductor device. In the inspection device for use, detecting means for detecting the peak value of the charging current flowing when the measuring terminal is brought into contact between the electrodes of the semiconductor element, and the peak value detected by this detecting means and a preset reference current value And a determining means for determining that the product is defective when the value obtained by the comparison is equal to or smaller than the reference current value. The inspection device for a semiconductor element of the present invention is a semiconductor element inspection device for applying a voltage between electrodes of a semiconductor element, detecting a current flowing through the semiconductor element, and determining whether the semiconductor element is defective. First detecting means for detecting the peak value of the charging current flowing when the measuring terminal is brought into contact between the electrodes of the element, and determining the peak value detected by the first detecting means and a preset reference current value. First comparing means for comparing, second detecting means for detecting a reverse current flowing following the charging current, a reverse current value detected by the second detecting means, and a preset reference reverse current A second comparison means for comparing the value with the first comparison means when the value obtained by the comparison by the first comparison means is equal to or less than a reference current value, and obtained by the second comparison means. Value is less than the reference reverse current value. It is characterized in further comprising a determining means to be defective in.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A composite semiconductor device according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a semiconductor device inspection apparatus according to a first embodiment of the present invention. In the figure, reference numeral A denotes a minute current detector, and a detecting means 11 for detecting the peak value P1 of the charging current IRc flowing when the measuring terminals 2A and 2B are brought into contact between the electrodes of the semiconductor element with the minute current detector A. , The peak value P detected by the detecting means 11
Comparing means 1 for comparing 1 with a preset reference current value
2 and a judging means 13 for judging a defective product when the value obtained by comparison by the comparing means 12 is equal to or less than the reference current value.

FIG. 2 is a block diagram of a semiconductor device inspection apparatus according to a second embodiment of the present invention. In this embodiment, the first detecting means 14 for detecting the same peak value of the charging current IRc as described above, and comparing the peak value P1 detected by the first detecting means 14 with a preset reference current value. The first comparing means 15 for performing the charging current IRc
A second detection means 16 for detecting a reverse current IRg flowing after the second detection step, and a second comparison for comparing the reverse current value detected by the second detection means 16 with a preset reference reverse current value. Means 17 and the value obtained by comparison by the first comparing means 15 is equal to or less than the reference current value, and
When the value obtained by the comparison by the second comparing means 17 is equal to or smaller than the reference reverse current value, the judging means 18 judges that the product is defective.
It is provided with.

Next, the microcurrent detector A including the above means is connected to the semiconductor device inspection apparatus 10 shown in FIG. 3, and the operation is performed as follows. That is, first, the measurement terminals 2A and 2B are brought into contact with the semiconductor element transferred here by the transfer device (not shown), here the diode D, and the switch S is closed. FIG. 4 shows the reverse current waveform from immediately after this until a predetermined time has elapsed.

In this figure, a is a peak value reference voltage preset for the peak value P1 of the charging current IRc. Also, b is a reverse current reference value preset from the peak value P1 of the charging current IRc to the reverse current IRg flowing continuously thereafter.

In the first embodiment, the detecting means 11 detects the peak value P1 of the charging current IRc. In the above case, the peak value P1 is a preset peak value reference voltage a
Since the above is detected, the data is compared by the comparing means 12 and the determining means 13 determines that the product is not defective, that is, is non-defective.

Further, in the second embodiment, the peak value P1 of the charging current IRc is detected by the first detecting means 14 and the second detecting means 16 as in the first embodiment.
To detect a reverse current IRg flowing after the charging current IRc. Then, the first comparing means 15 outputs the first
The peak value P of the charging current IRc detected by the detecting means 14 of FIG.
1 is compared with a preset peak value reference voltage a. Further, the reverse current IRg detected by the second detecting means 16 by the second comparing means 17 is compared with a preset reverse current reference value b. If the results of both cases, that is, if the peak value P1 is higher than the reference voltage a and the reverse current IRg is equal to or less than the reverse current reference value b, the determination unit 18 determines that the product is not defective, that is, is non-defective. You. If the reverse current IRg is larger than a preset reverse current reference value b, it is determined to be defective.

Next, the measuring terminals 2A and 2B are connected to the diode D
An example in which the electrodes are not in contact with each other will be described with reference to FIG. In this case, since the measurement terminals 2A and 2B are not in contact with the electrodes of the diode D, the peak value P2 of the charging current is relatively small as described above. Since this level is lower than the preset peak value reference voltage a, the subsequent reverse current I
Even when Rg is lower than a preset reverse current reference value b, it is determined to be defective.

As described above, in the first embodiment of the present invention,
Since the peak value P1 of the charging current IRc is detected, if the peak value P1 is lower than the preset peak value reference voltage a, the non-contact of the measuring terminals 2A and 2B with the device under test is detected. As a result, the inspection accuracy can be improved without such a device being determined as a non-defective product.

In the second embodiment, in addition to the above-mentioned means, a reverse current is detected by a second detecting means 16 and a second comparing means 17 and compared with a preset reverse current reference value b. Since the determination unit 18 for determining a defective product when the voltage is equal to or less than the reference value and equal to or less than the peak value reference voltage a is provided, a more accurate sorting inspection can be performed.

In the above embodiment, each detecting means 1
Although the specific circuit configurations of the comparison means 1, 14, 16 and the comparison means 12, 15, 17 and the determination means 13, 18 and the configuration of the microammeter A have not been described in detail, these can be realized by ordinary circuit configurations or means. That's why. In the above description, a diode has been described as an example of a device to be inspected. However, the present invention can be widely applied to a method and an apparatus for applying a reverse voltage to an element having a PN junction to perform an inspection.

[0018]

As described above, according to the present invention, as described above, if the measuring terminal of the semiconductor device inspection device is not in contact with the electrode of the device to be inspected, it can be reliably determined as a defective product. This has the effect that a high-precision inspection can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a semiconductor device inspection apparatus according to the present invention.

FIG. 2 is a block diagram showing a second embodiment of the semiconductor device inspection apparatus of the present invention.

FIG. 3 is a circuit diagram for explaining a method of inspecting a semiconductor device using the semiconductor device inspection apparatus.

FIG. 4 is a current waveform diagram when a reverse voltage is applied to the device under test.

FIG. 5 is a current waveform diagram when a measurement terminal of the inspection device is not in contact with a device under test.

FIG. 6 is a circuit diagram for explaining a method of inspecting a semiconductor device using a conventional semiconductor device inspection apparatus.

FIG. 7 is a current waveform diagram in a case where a measurement terminal in the conventional inspection apparatus is in contact with an element to be inspected.

FIG. 8 is a current waveform diagram in a case where a measurement terminal in the above-described conventional inspection device is not in contact with a device under test.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Inspection apparatus for semiconductor elements 11 Peak value detection means 12 Comparison means with reference current value 13 Defective product determination means 14 First detection means 15 First comparison means 16 Second detection means 17 Second comparison means 18 Defective product judgment means

Claims (2)

[Claims] A voltage is applied between electrodes of a semiconductor element,
In a semiconductor device inspection apparatus for detecting a current flowing through the semiconductor element and determining whether the semiconductor element is good or bad, a detecting means for detecting a peak value of a charging current flowing when a measurement terminal is brought into contact between electrodes of the semiconductor element. Comparing means for comparing the peak value detected by the detecting means with a preset reference current value, and determining that the product is defective if the value obtained by the comparison means is equal to or less than the reference current value. An inspection device for a semiconductor element, comprising: a determination unit. 2. Applying a voltage between electrodes of a semiconductor element,
In a semiconductor device inspection apparatus for detecting a current flowing in the semiconductor element and determining whether the semiconductor element is good or bad, a first value for detecting a peak value of a charging current flowing when a measurement terminal is brought into contact between electrodes of the semiconductor element. Detecting means;
First comparing means for comparing a peak value detected by the first detecting means with a preset reference current value, second detecting means for detecting a reverse current flowing following the charging current, A second comparing unit compares the reverse current value detected by the second detection unit with a preset reference reverse current value.
And the value obtained by the comparison by the first comparing means is equal to or less than the reference current value, and the value obtained by the comparison by the second comparing means is equal to or less than the reference reverse current value. And a determining means for determining a defective product in the case of (1).