CN109490735A - It is a kind of for measuring the device and method of electric current and/or voltage - Google Patents
It is a kind of for measuring the device and method of electric current and/or voltage Download PDFInfo
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- CN109490735A CN109490735A CN201811187082.XA CN201811187082A CN109490735A CN 109490735 A CN109490735 A CN 109490735A CN 201811187082 A CN201811187082 A CN 201811187082A CN 109490735 A CN109490735 A CN 109490735A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
- G01R31/2601—Apparatus or methods therefor
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Abstract
The present invention relates to a kind of for measuring the device of electric current and/or voltage, comprising: electric current to electric pressure converter is configured to be connected with equipment under test the output current signal for flowing through the equipment under test is converted into output voltage signal；And oscillograph, the waveform to show the output voltage signal is connect with electric current to electric pressure converter.By the invention it is possible to accuracy decline caused by the current distributing because of test loop be avoided, to provide the current/voltage measuring result with the high precision of high time precision.
Description
Technical field
Present invention relates in general to semiconductor test fields, in particular to one kind for measuring electric current and/or voltage
Device.Moreover, it relates to a kind of method for measuring electric current and/or voltage.
Background technique
With the progress of semiconductor technology, electronic device increasingly tends to small-sized, outputs and inputs current/voltage
Become therewith subtleer.In addition, the various electronic devices based on new material or new architecture also continuously emerge, the test to them
Higher time precision be may require to determine its performance or characteristic.And existing electron device testing system has been unable to satisfy survey
Examination required high current/voltage accuracy and high time precision.
Although existing high-precision AC source table can produce high-precision AC signal, to be synchronized with it
Signal measurement if, testing current precision is very limited, especially for pulsewidth less than the pulse signal of tens nanoseconds, surveys
Amount error is up to tens micromicroamperes.Although existing High-accuracy direct current source table can produce high-precision direct current signal, use
When it carrys out measuring signal, since its sample rate is very low, cause its time resolution excessively poor, only millisecond magnitude.
A kind of compromise testing scheme in the prior art is load resistance and equipment under test to be connected, thus by electric current
Signal is converted to voltage signal, and then oscillograph is parallel in test loop, to use oscilloscope measurement voltage signal.It is this
Testing scheme has higher time precision, direct measurement result of the current/voltage precision also above alternating current source table.However, due to
Oscillograph be test loop is accessed by way of in parallel with equipment under test, therefore can to the current distributing of test loop, from
And current/voltage measuring accuracy is caused to decline, the representative value of this shunt current is such as 1 micromicroampere or so.
Therefore, either individual source table system, or the parallel circuit of source table and load resistance is mutually tied with oscillograph
The method of conjunction all not can be implemented simultaneously the high-acruracy survey of current/voltage and time signal.However, with semiconductor technology
Development, especially the electronic device of new material new architecture, the demand to the test macro of high current/voltage and time precision are pole
It is urgent.
Summary of the invention
From the prior art, the task of the present invention is provide a kind of device for measuring electric current and/or voltage and side
Method, by the device or method, can to avoid the current distributing because of test loop caused by accuracy decline, so that providing has
The current/voltage measuring result of the high precision of high time precision.
In first aspect present invention, which is solved by a kind of for measuring the device of electric current and/or voltage, the dress
It sets and includes:
Electric current is configured to be connected with equipment under test will flow through the defeated of the equipment under test to electric pressure converter
Current signal is converted into output voltage signal out；And
Oscillograph connect the waveform to show the output voltage signal with electric current to electric pressure converter.
It should be noted here that in the present invention, " equipment under test " can both refer to electronic component, can also refer to circuit board or
Completed electronic equipment.
It is provided in another expansion scheme of the invention, the device further include:
Direct-flow input signal source is connect to provide direct-flow input signal for equipment under test with equipment under test；And
Ac input signal source is connect to provide ac input signal for equipment under test with equipment under test.
By the preferred embodiment, direct-flow input signal and ac input signal can be provided for equipment under test without external
Signal source, to complete various tests.It should be noted here that the signal source is either current signal source, is also possible to electricity
Signal source is pressed, and according to different types of signal source, it is also different from the connection type of equipment under test, i.e., with serial or parallel connection side
Formula accesses test loop.User can select as needed.
It provides in another preferred embodiment of the invention, the direct-flow input signal source is DC source table, and is exchanged defeated
Entering signal source is alternating current source table.By the preferred embodiment, high-precision direct current can be provided for equipment under test and believed with input is exchanged
Number, this is because existing direct current and alternating current source table can provide high-precision direct current and AC signal, therefore can be directly used as
High-precision signal source.
It is provided in another preferred embodiment of the invention, equipment under test is three terminal device.Three terminal device for example can be three
Pole pipe, transistor etc..In this case, electric current can be connect to electric pressure converter with the output end of three terminal device to test
Its output signal.It should be pointed out that in the present invention, equipment under test is either the device at both ends, such as resistance-variable storing device and phase transformation
Memory, the device for being also possible to three ends, such as transistor, but it is also possible to the new device etc. of more multiport.In multiport
In the case where device, input equipment provides enough port numbers to match device input port number.In the feelings of multiple output ends
Under condition, settable corresponding current/voltage converter and measuring channel oscilloscope number.
In the second aspect of the present invention, foregoing task is solved by a kind of for measuring the method for electric current and/or voltage,
This method includes the following steps:
Direct-flow input signal is provided for equipment under test；
Ac input signal is provided for equipment under test；
Electricity consumption flows to electric pressure converter and the output current signal of equipment under test is converted into output voltage signal；And
The waveform of the output voltage signal described in oscilloscope display.
It is provided in a preferred embodiment of the invention, this method further comprises the steps of:
The waveform of output voltage signal is converted into the waveform of output current signal.
For example, output voltage can be obtained to output electric current divided by resistance value, or output voltage is arrived divided by electric current
The conversion coefficient or conversion accuracy of electric pressure converter are to obtain output electric current.
The present invention at least has the advantage that (1) by the invention it is possible to obtain high-precision measurement result, this be because
It is the present invention using high-precision input signal source and simultaneously using the oscillograph of high measurement accuracy as measuring device, therefore can
To obtain high-precision result；(2) present invention is shown by will then connect after electric current to electric pressure converter and equipment under test series connection
Thus wave device avoid the current distributing effect of oscillograph in the prior art, improve measurement accuracy significantly；(3) this hair
It is bright of simple structure and low cost, it is suitable for large-scale application in semiconductor test field.
Detailed description of the invention
With reference to specific embodiment, the present invention is further explained with reference to the accompanying drawing.
Fig. 1 is shown according to prior art for measuring the block diagram of the device of electric current and/or voltage；
Fig. 2 shows according to the present invention for measuring the block diagram of the device of electric current and/or voltage；And
Fig. 3 shows according to the present invention for measuring the process of the method for electric current and/or voltage.
Specific embodiment
It should be pointed out that each component in each attached drawing may be shown in which be exaggerated in order to illustrate, and it is not necessarily ratio
Example is correctly.In the drawings, identical appended drawing reference is equipped with to the identical component of identical or function.
In the present invention, unless otherwise indicated, " on being arranged in ... ", " being arranged in ... top " and " on being arranged in ... "
Do not exclude the case where there are intermediaries therebetween.
In the present invention, each embodiment is intended only to illustrate the solution of the present invention, and is understood not to restrictive.
In the present invention, unless otherwise indicated, quantifier "one", " one " and the scene for not excluding element.
It is also noted herein that in an embodiment of the present invention, for it is clear, for the sake of simplicity, might show only one
Sub-unit or component, but those skilled in the art are it is understood that under the teachings of the present invention, it can be according to concrete scene
Need to add required component or component.
It is also noted herein that within the scope of the invention, the wording such as " identical ", " equal ", " being equal to " are not meant to
The two numerical value is absolutely equal, but allows certain reasonable error, that is to say, that the wording also contemplated " substantially phase
Together ", " being essentially equal ", " being substantially equal to ".
In addition, the number of the step of each method of the invention limit the method step execute sequence.Unless special
It does not point out, various method steps can be executed with different order.
Fig. 1 is shown according to prior art for measuring the block diagram of the device 100 of electric current and/or voltage.
The present invention is based on the uniquenesses of inventor to see clearly: conventional current/voltage measuring system in order to guarantee high time precision,
Using DC source table 101 and alternating current source table 104 respectively as the direct current and alternating message source of equipment under test 103；Simultaneously as
The waveform that oscillograph 105 can only measure voltage, show voltage signal, therefore equipment under test 103 is connected with load resistance 102
Afterwards, then it is oscillograph 105 is in parallel with equipment under test 103 to measure the voltage on equipment under test 103, wherein in this way may be used
To obtain the measurement result of high-precision input signal and high time precision；However the disadvantages of this solution is, oscillograph 105
The electric current for flowing through equipment under test 103 can be shunted, so that the voltage on equipment under test 103 becomes smaller, to influence measurement knot
The precision of fruit, such as the internal resistance of oscillograph 105 is usually 50 ohm or 1 megohm, this makes this parallel connection branch of oscillograph 105
Road can generate current distributing effect to equipment under test 103, even if oscillograph 105 selects 1 megohm, can also generate close to 1 microampere
The shunting of training, to limit testing current precision；After the present invention with equipment under test by connecting electric current to electric pressure converter
Then oscillograph is connected, the current distributing effect of oscillograph in the prior art is avoided, improves measurement essence thus significantly
Degree.
The present invention is further explained with reference to the accompanying drawings and examples.
Fig. 2 shows according to the present invention for measuring the block diagram of the device 200 of electric current and/or voltage.
As shown in Fig. 2, device 200 includes electric current to electric pressure converter 204 and oscillograph 205, but optionally can wrap
Include direct-flow input signal source 201 and ac input signal source 202 with to equipment under test 203 provide high-precision direct current with exchange it is defeated
Enter signal, wherein equipment under test 203 both can be semiconductor devices, or circuit or electronic equipment.Direct-flow input signal
Source 201 and ac input signal source 202 are also possible to voltage signal source either current signal source, and according to different type
Signal source, it is also different from the connection type of equipment under test, i.e., access test loop in series or in parallel.
Electric current is connected to electric pressure converter 204 with equipment under test 203, and wherein electric current to electric pressure converter 204 is for will be by
The current signal of measurement equipment 203 is converted to voltage signal.Electric current can be commercially available electric current to electric pressure converter 204 and convert to voltage
Device module comprising conversion circuit, the conversion circuit is for example including amplifier and feedback resistance.It is right in order not to the fuzzy present invention
The details of electric current to electric pressure converter 204 is not further spread out.
Oscillograph 205 is connected with electric current to electric pressure converter 204, to measure its voltage signal (corresponding current signal
It can convert to obtain from voltage signal).
The operation logic of the device of the invention 200 is described below.
In terms of signal input, the direct current and ac input signal of equipment under test 203 are respectively from 201 He of DC source table
Alternating current source table 202, wherein DC source table 201 and alternating current source table 202 are mainly used for providing high-precision input signal.According to user
Demand and application, other signals source are also conceivable.It, can be with by using the high accuracy source table of existing business maturation
High-precision electric current, voltage signal are generated, in alternating-current measurement, the time precision of pulse signal also can achieve high-precision.Value
It is noted that DC source table 201 with alternating current source table 202 although measurement electric current/electricity that can be synchronous while generating signal
Signal is pressed, but due to itself technical restriction of DC source table 201 and alternating current source table 202, there is larger measurement errors.Such as
For DC source table 201, sample rate is extremely low, usually less than 1kSa/s, this causes the time precision of test lower, it is desirable that test
Signal frequency is lower than 1kHz.For alternating current source table 202, testing current precision is lower, below especially for tens nanoseconds
Pulse signal, the noise of testing current has reached tens micromicroamperes, while its sample rate is not also high, only 200MSa/s.
In terms of signal measurement, in order to cope with aforementioned source table 201 and 202 current precision on measurement pulse signal
The problem of, present invention employs electric currents to voltage signal converter 204 to return the test that the series connection of oscillograph 205 enters equipment under test
Road.It is compared with traditional oscillograph parallel connection test macro (referring to Fig. 1), the device of the invention can guarantee the electricity of test simultaneously
Stream/voltage accuracy and time precision.The present invention uses oscillograph 205 and the concatenated mode of equipment under test 203, avoids shunting effect
It answers, using advantage of the oscillograph 205 on time resolution and voltage measurement accuracy, realizes the high time essence of equipment under test
Degree, high voltage precision (voltage tester result can be converted to results of weak current) measurement.Using the electronics device of the device of the invention 200
Part test macro can be realized the current/voltage electron device testing of high current/voltage accuracy and time precision.
The present invention at least has the advantage that (1) by the invention it is possible to obtain high-precision measurement result, this be because
It is the present invention using high-precision input signal source and simultaneously using the oscillograph of high measurement accuracy as measuring device, therefore can
To obtain high-precision result；(2) present invention is shown by will then connect after electric current to electric pressure converter and equipment under test series connection
Thus wave device avoid the current distributing effect of oscillograph in the prior art, improve measurement accuracy significantly；(3) this hair
It is bright of simple structure and low cost, it is suitable for large-scale application in semiconductor test field.
Fig. 3 shows the process of the method 300 according to the present invention for being used to measure electric current and/or voltage, wherein dotted line frame
Indicate optional step.
In step 302, direct-flow input signal is provided for equipment under test 203.This can be by direct-flow input signal source come real
It is existing.User can select the direct-flow input signal source of different accuracy according to demand.
In step 304, ac input signal is provided for equipment under test 203.This can be by ac input signal source come real
It is existing.User can select the ac input signal source of different accuracy according to demand.
In step 306, electricity consumption flows to electric pressure converter 204 and the output current signal of equipment under test is converted into output voltage
Signal is connected with oscillograph 205 again after wherein electric current is connected to electric pressure converter 204 with equipment under test 203, so that whole process
There is no shunt effects, thereby guarantee that higher measurement accuracy.
In step 308, the waveform of the output voltage signal is shown with oscillograph 205.The essence of high time of oscillograph 205
Degree and high voltage precision can guarantee measurement result Time precision with higher and voltage accuracy, and (corresponding current signal can
Convert to obtain from voltage signal), in order to accurately test the electrology characteristic of electronic device, electronic equipment or circuit at any time.
In optional step 310, the waveform of output voltage signal is converted into the waveform of output current signal.This can pass through
Simple conversion is for example realized divided by current-voltage conversion coefficient.
Although some embodiments of the present invention are described in present specification, those skilled in the art
Member is it is understood that these embodiments are merely possible to shown in example.Those skilled in the art under the teachings of the present invention may be used
To expect numerous variant schemes, alternative solution and improvement project without beyond the scope of this invention.The appended claims purport
It is limiting the scope of the invention, and is covering the method in the range of these claims itself and its equivalents and knot whereby
Structure.
Claims (6)
1. a kind of for measuring the device of electric current and/or voltage, comprising:
Electric current is configured to be connected with equipment under test will flow through the output of equipment under test electricity to electric pressure converter
Stream signal is converted into output voltage signal；And
Oscillograph connect the waveform to show the output voltage signal with electric current to electric pressure converter.
2. the apparatus according to claim 1, further includes:
Direct-flow input signal source is connect to provide direct-flow input signal for equipment under test with equipment under test；And
Ac input signal source is connect to provide ac input signal for equipment under test with equipment under test.
3. the apparatus of claim 2 wherein the direct-flow input signal source is DC source table, and exchanges input letter
Number source is alternating current source table.
4. the apparatus according to claim 1, wherein equipment under test is three terminal device.
5. a kind of method for measuring electric current and/or voltage, including the following steps:
Direct-flow input signal is provided for equipment under test；
Ac input signal is provided for equipment under test；
Electricity consumption flows to electric pressure converter and the output current signal of equipment under test is converted into output voltage signal；And
The waveform of the output voltage signal described in oscilloscope display.
6. according to the method described in claim 5, further comprising the steps of:
The waveform of output voltage signal is converted into the waveform of output current signal.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811187082.XA CN109490735A (en) | 2018-10-12 | 2018-10-12 | It is a kind of for measuring the device and method of electric current and/or voltage |
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| CN201811187082.XA CN109490735A (en) | 2018-10-12 | 2018-10-12 | It is a kind of for measuring the device and method of electric current and/or voltage |
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Application publication date: 20190319 |