JP2001296328A - Testing device for prescribed test item with reference to apparatus to be measured - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a testing device, for a prescribed item with reference to an apparatus to be measured, by which a noise is detected in real time and at once and which can urge the early solution of a problem when a test result is affected. SOLUTION: The testing device is constituted in such a way that the test item which is set according to predetermined measuring specifications with reference to the apparatus is executed to the apparatus, that an input signal which corresponds to the test item is input to the apparatus, that a measuring signal from the apparatus due to the application of the input signal is measured so as to fetch measured data, that a measuring condition which corresponds to the test item with reference to the apparatus is set in advance or on the basis of the measured data and that noise data which is obtained by measuring the noise is a desired position in the apparatus, according to the set condition is matched to the set condition is decided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a function of monitoring a state of any noise source affecting a measurement result of a device under test (DUT) in a semiconductor test apparatus and issuing a warning. It is about.

[0002]

2. Description of the Related Art Conventionally, in order to solve the problem of noise generated during a DUT test, input / output and power supply pin voltage are assumed based on information on test environment conditions inferred from measurement results of a semiconductor test apparatus. Has been measured with measuring equipment, the cause has been identified from the data, and countermeasures have been taken accordingly. Such measures are usually taken during the development of a test program.In this case, when a test result that is considered appropriate is obtained, for example, by comparing test results using non-defective samples with other measurement equipment. Finally, it is determined that the measurement circuit and test program have been completed.

[0003]

However, the test environment finally used is often different from the work environment at the time of development performed earlier. That is, it is the influence on the DUT due to disturbance centered on noise. If a difference occurs in the test result due to the disturbance, it is necessary to repeat the same operation as at the time of development to take a countermeasure for the cause. Also,
In some cases, it may be necessary to take measures against temporary or sudden noise, as well as the effect of increased noise components due to aging of test equipment, but in most cases, appropriate measures have not been taken. It is. For example, in the conventional device, the influence of noise is limited only to the determination based on the test result. Therefore, in order to determine and cope with the specific cause due to noise, it is necessary to use another device, It takes a lot of time for the operation.
In many cases, such devices are not always prepared in a test factory, and there is a case where it is difficult to confirm the noise.

SUMMARY OF THE INVENTION The present invention provides a method for detecting a noise in a device under test capable of detecting noise in real time or immediately and, when the result of the test is affected, prompting the solution of the problem at an early stage. The present invention provides a test and measurement device for items.

[0005]

In order to achieve this object, a test measuring apparatus for a predetermined test item for a device under test according to the present invention includes a test item set according to a predetermined measurement specification for the device under test. A signal generator for generating an input signal corresponding to the test item, an input signal applying means for inputting the input signal to the device to be measured, A measuring signal extracting means for extracting a measuring signal from the device under measurement, a measuring instrument for measuring the measuring signal extracted through the measuring signal extracting means and outputting the measured signal as measurement data, A controller that sets measurement conditions corresponding to the test items in advance or based on the measurement data; and a controller that sets the measurement conditions according to the condition setting from the controller. A noise monitor for outputting the noise data measured noise in Nozomu position,
The controller is configured to further include a determination function of determining whether the noise data from the noise monitor meets the condition setting. The controller may be configured to output a determination result by the determination function for each of the noise data from the device under test. Further, the controller may be configured to output a result of the determination by the determination function with respect to the noise data from the device under test at predetermined intervals.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the present invention, a detection function is incorporated as a system into a semiconductor inspection apparatus as a main body.
One of the features is that noise can be monitored immediately. That is, in order to solve the problems of the prior art as described above, the function of the present invention that operates as a part of the semiconductor inspection apparatus allows the user to always set an arbitrary part of the measurement system with respect to the target part where the influence of noise is a problem. And the timing and limit level of monitoring can be specified on the test program. Further, the detection result is monitored for each DUT, and when the noise reaches a specified level position, a warning can be issued to notify an abnormality. Depending on the setting method on the program, classification based on the type, level, or the like is also possible.

[0007]

FIG. 1 is a diagram showing an embodiment of the present invention. 1
Is a noise monitor, 2 is a controller, 3 is a signal generator, 4 is a measuring instrument, 5 is a DUT board, 6 is an IC to be measured,
7 is an input signal cable, 8 is a measurement signal cable, 9 is a noise measurement probe, and 11 is a classification device. 1,2,
3 and 4 are included in the semiconductor inspection apparatus main body.

FIG. 3 is an operation timing chart for explaining the operation of the device of the present invention shown in FIG. The operation of the device of the present invention shown in FIG. 1 will be described with reference to FIG. The conditions of the noise monitor 1 are set in consideration of the circuit configuration of the IC to be measured, applied voltage, past measurement data, and the like.
The input signal generated from the signal generator 3 of the present device passes through the input signal cable 7 and the DUT 6 in the DUT board 5.
And is measured by the measuring device 4 through the measuring signal cable 8 and determined by the controller 2. here,
A noise measuring probe 9 for noise monitoring is selected and connected to a portion that is easily affected by noise.

The input signals generated from the signal generator 3 and input to the DUT 6 via the input signal cable 7 include a sine wave of a single frequency, a multitone, a digital clock pulse, an impulse, a video signal, a DC voltage, It is a signal determined by selecting a signal format suitable for the measurement conditions for the DUT, such as a DC sweep waveform.

Further, what is taken out via the measuring signal cable 8 and measured by the measuring instrument 4 is the D signal for the input signal.
The output level, frequency, and the like from the UT 6. FIG. 4 (a)
Is an example of a measured waveform in this case. Here, the condition setting from the controller 2 to the noise monitor 1 may be changed based on the observation result of the measured waveform.

Further, what is measured by the noise monitor 1 via the noise measuring probe 9 is a noise level, a frequency component, a waveform, and the like. The frequency component is measured for each frequency component contained by using a spectrum analyzer. Level can be measured. As for the noise waveform, information on the type of noise, such as white noise, impulse noise, and induction noise, and level distribution can be obtained using a CRT or the like. FIG.
(B) is an example of the measurement data in this case. Here, + L _th is positive determination level, -L _th is negative judgment level.

At this time, various conditions relating to noise measurement are described on a test program or in a "noise measurement condition file" which can be controlled by the test program. The contents include the frequency component of the noise to be measured, the determination level (for example, several mV), the determination timing, and the like. When the program is executed, noise and noise
The monitor 1 performs the measurement and sets N in FIG.
A flag is set when the determination level is exceeded, as at the p point, and an “NG / flag” is sent to the controller 2 together with the data at the determination timing. The controller 2 determines the result according to a predetermined criterion according to the DUT measurement specification, and sends the determination output to the classification device 11 such as a handler.

This operation is repeated for each DUT measurement. A plurality of noise measurement points can be set, and the determination conditions can be set as appropriate for each test item.

FIG. 2 shows another embodiment of the noise measurement in the semiconductor inspection apparatus. A noise measurement of the power supply 10 in the test apparatus is performed regardless of whether the operation related to the DUT measurement is performed or not. This is a use method for detecting in advance an increase in noise due to aging or the like described above. For a signal generator, a measuring device, a power supply, and the like, which are regarded as noise sources, for example, at regular intervals, such as at regular intervals, at regular intervals, at regular intervals, such as at regular intervals, such as at regular intervals, such as at regular intervals. And it is performed continuously.

Data is managed by the system so that data can be accumulated for each measurement point taking into account aging.

[0016]

As described above in detail, according to the present invention, it is possible to prevent the measurement and trouble due to the temporary abnormal noise of the DUT peripheral circuit. Further, by monitoring a specific point of the semiconductor inspection apparatus itself for a long period of time, it is possible to detect an increase in noise due to aging, etc. That is, problems of the type relating to noise can be detected and resolved at an early stage, so that an optimal test environment can always be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram showing another embodiment of the present invention.

FIG. 3 is an operation timing flowchart of the device of the present invention.

FIG. 4 shows a measured waveform (a) when a DUT is applied and a waveform (b) for explaining a determination operation by a noise monitor in the apparatus of the present invention.

[Explanation of symbols]

 Reference Signs List 1 noise monitor 2 controller 3 signal generator 4 measuring instrument 5 DUT board 6 DUT 7 input signal cable 8 measurement signal cable 9 noise measurement probe 10 power supply 11 classification device

Claims (3)

[Claims] 1. A signal generator for generating an input signal corresponding to a test item in order to execute a test item set according to a predetermined measurement specification for the device under test on the device under test, and the input signal Means for applying an input signal to the device under test, a means for taking out a measurement signal from the device under test accompanying the application of the input signal, and a means for taking out a measurement signal. A measuring device that measures the measured signal and outputs the measured data as measurement data; a controller that sets measurement conditions corresponding to the test items for the device under test in advance or based on the measurement data; and setting the conditions from the controller. And a noise monitor that outputs noise data obtained by measuring noise at a desired position in the device under test. , Said noise data testing apparatus for measuring a predetermined test item with respect to the measuring device configured to further include a determination function of determining whether to meet the condition set from the noise monitor. 2. The device under test according to claim 1, wherein the controller is configured to output a determination result by the determination function for each of the noise data from the device under test. Test measurement device for specified test items. 3. The controller according to claim 2, wherein the controller outputs a result of the determination by the determination function to the noise data from the device under test at predetermined intervals. A test and measurement device for a predetermined test item for the device to be measured according to claim 1.