JP2836655B2 - Semiconductor device measuring equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device measuring apparatus, and more particularly, to a semiconductor device measuring apparatus for measuring a plurality of electrical characteristic measurement items.

[0002]

2. Description of the Related Art FIG.
As shown in FIG. 1, the test code storage unit 1, the CPU 2,
It comprises a test power supply 3, a measurement circuit switching unit 4, and a measured value reading unit 5, and the semiconductor device 6 to be measured is connected to the measurement circuit switching unit 4. Then, as shown in FIG. 3, a constant voltage power supply circuit 9 and a constant current circuit 10, which are test power supplies 3,
The voltage measurement circuit 11 and the current measurement circuit 12 as the measurement value reading unit 5 are replaced with the relays K1 to K12 as the measurement circuit switching unit 4.
Semiconductor device 6 under on / off combination
And a test circuit corresponding to the measurement item.

Next, the operation will be described. FIG. 6 is an operation flowchart of a conventional semiconductor device measuring apparatus. First, in step B1, the semiconductor device measurement apparatus receives a test start signal from an external device using a start switch (not shown) or the like, and starts a test. Next, step B
In step 2, the CPU 2 reads one test code from the test code string stored in the test code storage unit 1. Next, in step B3, the CPU 2 issues a command to the measurement circuit switching section 4 in accordance with the read test code to switch the measurement circuit. For example, the relays K1 and K12 in FIG.
K11 is turned off. Next, in step B4, the CPU 2 operates the test power supply 3 to apply a bias to the semiconductor device 6 to be measured. Next, in step B5, the CPU 2 reads the measured value from the measured value reading section 5. Next, in step B6, the CP
U2 causes the test power supply 3 to stop bias application. Next, in step B7, the CPU 2 causes the measurement circuit switching section 4 to open all the relays K1 to K12. Next, in step B8, the CPU 2 reads the next test code from the test code string in the test code storage unit 1. Next, at step B9, C
It is confirmed from the test code read by PU2 whether or not all the measurement items have been completed, and the processing of steps B3 to B9 is repeated until the measurement is completed.

In FIG. 6, if the processing times of steps B3 to B6 are t ₁ to t ₄ and the processing times of steps B7 and B8 are t ₈ and t ₉ , respectively, the time required for measuring one item is t ₁ + t. ₂ + t ₃ + t ₄ + t ₈ + t ₉ .

[0005]

However, in this conventional semiconductor device measuring apparatus, each item is 1
One of each measurement, for switching the measuring circuit, in the case of continuously measuring the measurement item using the same measuring circuit, open t ₈ relays, and performing unnecessary processing of switching t ₁ of the measurement circuit, the processing There was a problem that time was long.

Accordingly, a technical object of the present invention is to provide a semiconductor device measuring apparatus which can reduce the processing time in view of the above-mentioned drawbacks.

[0007]

According to the present invention, there are provided a plurality of measurement circuits, and a plurality of measurement items relating to electrical characteristics of a semiconductor device are measured.
In a semiconductor device measurement device that performs measurement using a measurement circuit corresponding to each measurement item indicated by each test code in a test code sequence, a first storage unit that stores the test code sequence and, prior to the measurement, First comparing means for sequentially comparing each test code with the rest of the test codes in the test code string stored in the first storage unit; and storing the stored test codes based on a comparison result of the first comparing means. A second storage unit for storing a modified test code sequence obtained by rearranging the columns so that the same test codes are arranged continuously, and each test of the modified test code sequence stored in the second storage unit Reading means for reading a code and outputting it as a read test code; and switching to a measuring circuit corresponding to a measurement item indicated by the read test code. The switching means, the second comparing means for comparing the read test code with the test code previously read from the second storage unit, and the comparison result of the second comparing means being the same. In the case of the test code, the measuring circuit corresponding to the measurement item indicated by the previously read test code has a holding unit for holding the switching state of the switching unit. A semiconductor device measuring device is obtained.

That is, a semiconductor device measuring apparatus according to the present invention comprises: a switching unit for a measuring circuit; a storage unit for storing a test code; a unit for comparing the preceding and succeeding test codes in the stored test code; There are provided means for holding, means for sequentially comparing all the stored test code strings, and means for restoring the stored test code strings.

[0009]

Next, an embodiment of the present invention will be described with reference to the drawings.

First, a semiconductor measuring device on which the present invention is based will be described. FIG. 1 is a flowchart showing the operation sequence of the semiconductor measuring device on which the present invention is based, and FIG. 2 is a configuration diagram of the present semiconductor measuring device.

The present semiconductor measuring device includes a test code storage unit 1, a CPU 2, a test power supply 3, a measurement circuit switching unit 4,
, A measurement reading unit 5, a test code comparison unit 7, and a holding unit 8. The semiconductor device 6 to be measured is connected to the measurement circuit switching unit 4. As shown in FIG. 3, the constant voltage power supply circuit 9 and the constant current circuit 10 as the test power supply 3 and the voltage measurement circuit 11 and the current measurement circuit 12 as the measurement value reading unit 5 are the measurement circuit switching unit 4. Relay K1
The test circuit is selectively connected to the semiconductor device 6 to be measured by on / off combinations of K12 to K12 to configure a test circuit corresponding to the measurement item.

Next, an operation sequence in a case where measurement is performed according to an arbitrary test program will be described with reference to FIG.

In step A1, the semiconductor measuring apparatus receives a test start signal from the outside by a start switch (not shown) or the like, and starts a test. Next, step A
In step 2, the CPU 2 reads one test code from the test code string stored in the test code storage unit 1. Next, in step A3, the CPU 2 issues a command to the measurement circuit switching unit 4 according to the read test code, and switches the measurement circuit. For example, the relays K1 and K12 in FIG.
To K11 are turned off. Next, in step A4, the CPU 2 operates the test power supply 3 to apply a bias to the semiconductor device 6 to be measured. Next, in step A5, the CPU 2 reads the measured value from the measured value reading section 5. Next, in step A6, C
The PU 2 causes the test power supply 3 to stop applying the bias.

Next, at step A7, the CPU 2 reads out the test code of the measuring circuit currently used from the test code storage section 1 again. Next, in step A8, the CPU 2 reads the next test code from the test code string in the test code storage unit 1.

Next, in step A9, the two test codes read by the CPU 2 before and after are compared by the test code comparing section 7 to confirm whether the test codes match.

If the test codes match, for example, if the relays K1 and K12 in FIG. 3 are on and K2 to K11 are off, the process proceeds to step A14, where the CPU 2 issues a measurement circuit holding instruction to the holding unit 8. The measurement circuit switching section 4 proceeds to step A4 while keeping the current measurement circuit, operates the test power supply 3, starts measurement of the next measurement item, and repeats the processing after step A4.

If the test codes do not match in step A9, the process proceeds to step A10, where the CPU 2 causes the measurement circuit switching section 4 to open all the relays K1 to K12. Next, in step A11, the CPU 2 reads the next test code again from the test code string in the test code storage unit 1. Next, it is checked whether all the measurement items have been completed based on the test code read by the CPU 2 in step A12, and the processing in steps A3 to A12 is repeated until the measurement is completed.

In FIG. 1, the processing times of steps A3 to A11 are t ₁ to t ₉ , respectively, and the processing time of step A14 is t ₁₀
Then, the processing time for continuously measuring the measurement items of the same test code is t ₂ + t ₃ + t ₄ + t ₅ + t ₆
+ T ₇ + t ₁₀ , and the processing time of t ₁ , t ₈ , and t ₉ can be omitted as compared with the conventional semiconductor device measuring apparatus.
t _5, t _6, the processing time t _7, t ₁₀ will be added. Here, t ₅ , t ₆ , t ₇ , t ₉ , and t ₁₀ are several μsec because they are processing times of the CPU, and t ₁ and t ₈ are about 3 msec because they are relay driving times.

If the difference between the processing times for measuring one item between the conventional semiconductor device measuring apparatus and the semiconductor device measuring apparatus according to the present invention is Δt, then Δt = (t ₅ + t ₆ + t ₇₎
+ T ₁₀₎ - a _{(t 1 + t 8 + t} 9). Here, as described above, the processing time of the CPU, t ₅ , t ₆ , t ₇ , t
_9, the number μsec of the order of t _10, since it is possible to ignore against the order of about 3msec of t ₁ and t ₈ is a relay driving time, ignoring, Delta] t is about - (t ₁ + t
₈ ), which is approximately -6 msec. That is, this semiconductor measuring device can save about 6 msec when executing the same test code.

Next, a semiconductor device measuring apparatus according to an embodiment of the present invention will be described. In this embodiment, prior to the measurement,
Means for changing the test program shown in (1) of FIG. 5 to a test program capable of continuously measuring measurement items of the same test code as shown in (5) of FIG. to add.

FIG. 4 shows the configuration of a semiconductor device measuring apparatus according to an embodiment of the present invention. The semiconductor device measuring apparatus (FIG. 2) on which the present invention is based has a configuration in which a test code restoring unit 13 is added. Has become.

As an example, it is assumed that a test program as shown in FIG.
First, as shown in FIG. 5B, the CPU 2 takes out the first test code B from the test code storage unit 1 and stores it in the test code re-storage unit 13. Next, the CPU 2 sequentially compares the test codes in the test code storage unit 1 and
If exists, it is extracted and stored in the test code re-storage unit 13 (FIG. 5 (3)). Next, the CPU 2 extracts the first test code, that is, the test code C, from the remaining code in the test code storage unit 1 and stores it in the test code re-storage unit 13 (FIG. 5D). The above processing is repeated, and finally the test code string is stored in the test code re-storing unit 13 as shown in FIG.
The second and subsequent measurement processes are started. At this time, the CPU 2 reads the test code from the test code restoring unit 13.

[0023]

As described above, according to the present invention, the previous and next test codes are compared, and if the test code is the same, the measurement circuit is not switched, and the measurement circuit at that time is held. Since the semiconductor device has the function of performing the measurement, the measurement time of the semiconductor device is shortened, and the processing capability of the sorting process is improved.

Further, the present invention has a function of changing the test program so that the measurement items of the same test code are continuously measured, so that the measurement items of the same test code are continuously measured when the test program is input. It has the consequence that it does not need to be considered.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an operation sequence of a semiconductor device measuring apparatus on which the present invention is based.

FIG. 2 is a configuration diagram of a semiconductor device measuring apparatus on which the present invention is based.

FIG. 3 is a diagram illustrating details of a test power supply, a measurement circuit switching unit, and a measurement value reading unit in FIG. 2;

FIG. 4 is a configuration diagram of a semiconductor device measuring apparatus according to an embodiment of the present invention.

FIG. 5 is a diagram for explaining a storage state of a test code re-storage section 13 of FIG.

FIG. 6 is a flowchart showing an operation sequence of a conventional semiconductor device measuring apparatus.

FIG. 7 is a configuration diagram of a conventional semiconductor device measuring apparatus.

[Explanation of symbols]

 Reference Signs List 1 Test code storage unit 2 CPU 3 Test power supply 4 Measurement circuit switching unit 5 Measurement value reading unit 6 Semiconductor device under test 7 Test code comparison unit 8 Holding unit 9 Constant voltage power supply circuit 10 Constant current power supply circuit 11 Voltage measurement circuit 12 Current measurement Circuit 13 Test code restoring unit K1 to K12 Relay

Claims (1)

(57) [Claims] 1. A method for measuring a plurality of measurement items related to electrical characteristics of a semiconductor device, comprising: a plurality of measurement circuits; and performing each measurement indicated by each test code in a test code string among the plurality of measurement circuits. Using the measurement circuit corresponding to the item,
In the semiconductor device measurement apparatus to be performed, a first storage unit for storing the test code sequence, and before the measurement, each test code in the test code sequence stored in the first storage unit is sequentially compared with the remaining test codes. And a modified test code sequence obtained by rearranging the stored test code sequence such that the same test code is continuous based on the comparison result of the first comparing device. A second storage unit for storing, a read unit for reading each test code of the modified test code string stored in the second storage unit, and outputting the read test code as a read test code; Switching means for switching to a measurement circuit corresponding to the measurement item indicated by.
The second comparison with the test code read from the storage unit of
If the comparison result of the second comparison means is the same test code, the switching circuit is connected to the measurement circuit corresponding to the measurement item indicated by the previously read test code. And a holding means for holding a switching state of the semiconductor device.