CN103472308B - Layer material is carried out FOUR-POINT PROBE METER and the method for testing thereof of nondestructive measurement - Google Patents
Layer material is carried out FOUR-POINT PROBE METER and the method for testing thereof of nondestructive measurement Download PDFInfo
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Abstract
The invention discloses a kind of FOUR-POINT PROBE METER and method of testing thereof that layer material is carried out nondestructive measurement, this tester includes ruby Four probing pin probe, testing jig, main frame, Measurement and Control System, test voltage actuator and constant-current source break-make switching switch, constant-current source circuit and power circuit is included in main frame, test voltage actuator is arranged between power circuit and Four probing pin probe, for regulating in Four probing pin probe the test voltage between two outer probes before the test begins.Constant-current source break-make switching switch is arranged between constant-current source circuit and Four probing pin probe, is used for controlling to press to touch completely at probe tip just to connect constant-current source circuit behind layer material surface.The invention also discloses the method for testing based on above-mentioned tester.The present invention can regulate the test voltage of 1,4 probes, it is to avoid occur high-voltage breakdown, ruby Four probing pin probe has appropriate radius of curvature and pressure, probe pressure can 25-250g in a big way in change, it is possible to be widely used in measuring various Novel thin layer material.
Description
Technical field
The present invention relates to FOUR-POINT PROBE METER research field, particularly to a kind of FOUR-POINT PROBE METER and method of testing thereof that layer material is carried out nondestructive measurement.
Background technology
Coating and thin-film material are primarily referred to as the layer material formed on a silicon substrate by diffusion layer, extension, ion implanting, chemical gaseous phase or other depositing technics, and square resistance (also known as surface resistance) is development, produces the important parameter must measured in layer material process.Layer material square resistance method of testing conventional both at home and abroad at present is four probe method, and its test device is generally made up of Four probing pin probe, testing jig, main frame, Measurement and Control System.Wherein testing jig includes sample stage, cantilever, Four probing pin probe is fixed on cantilever, can lift on cantilever, the central axis of probe and the centering of sample stage center, main frame is arranged on the side of testing jig, including casing and the test circuit being arranged on box house, Four probing pin probe is connected with test circuit, and test circuit includes power circuit, constant-current source circuit.Four detecting heads are also connected with the voltage detecting circuit in Measurement and Control System.Test philosophy is: layer material is placed on testing jig platform, four vertical being arranged in a row of equidistant probe of Four probing pin probe, apply suitable pressure to make it form ohm with sample surface to be connected, give two outer probes (1,4 probe) a logical small area analysis with constant-current source, voltage detecting circuit measures the voltage between inner side two probes (2,3 probe), voltage signal is converted into square resistance by internal change-over circuit by the processing module in Measurement and Control System, then displays.
But existing layer material square resistance test equipment, 1,4 current probe both end voltage are often excessive, and lack measurement protection device, it is easy to electric breakdown phenomena occurs, layer material is caused electrical damage；It addition, the probe radius of curvature of probe is generally made too small, contact pressure is also excessive, and layer material can cause pressure wear or the mechanical damage of pressure break.
Accordingly, it would be desirable to a kind of test voltage is adjustable, probe has again appropriate radius of curvature and pressure for layer material measurement FOUR-POINT PROBE METER and method of testing.
Summary of the invention
Present invention is primarily targeted at the shortcoming overcoming prior art with not enough, a kind of FOUR-POINT PROBE METER that layer material carries out nondestructive measurement is provided, this tester test time to layer material without electrically and mechanically damaging, it is thus possible to be widely used in measuring various Novel thin layer material.
Another object of the present invention is to the shortcoming overcoming prior art with not enough, it is provided that a kind of method of testing based on above-mentioned tester.The method can regulate test voltage and regulate electric current, it is achieved Non-Destructive Testing.
The purpose of the present invention is realized by following technical scheme: layer material carries out the FOUR-POINT PROBE METER of nondestructive measurement, including Four probing pin probe, testing jig, main frame, Measurement and Control System, constant-current source circuit and power circuit is included in main frame, FOUR-POINT PROBE METER also includes test voltage actuator, test voltage actuator is arranged between power circuit and Four probing pin probe, for regulating in Four probing pin probe the test voltage between two outer probes before the test begins.By arranging test voltage actuator, it is possible to regulate test voltage in advance, wear so that it is guaranteed that layer material will not be electrically shocked because of overtension.
Concrete, described test voltage actuator includes a potentiometer, and this potentiometer one end is connected with power circuit, and the other end is connected with one of them outer probe.Such that it is able to the test voltage between two outer probes is adjusted by the principle according to electric resistance partial pressure.
Preferably, described FOUR-POINT PROBE METER also includes constant-current source break-make switching switch, and constant-current source break-make switching switch is arranged between constant-current source circuit and Four probing pin probe, is used for controlling to press to touch completely at probe tip just to connect constant-current source circuit behind layer material surface.Can avoid, when energising, the air electrical breakdown spark phenomenon between probe tip and layer material surface occurs by arranging constant-current source break-make switching switch.
Preferably, the casing of described main frame is provided with human-computer interaction interface, test voltage actuator adjusting knob and constant-current source break-make switching switch are respectively provided with on the surface, also being provided with display screen on this interface, display screen is for externally showing parameter and the measurement result of each parts of current setting simultaneously.
Preferably, described Four probing pin probe is ruby Four probing pin probe, is connected with main frame by having the quad line of function of shielding.
Further, described ruby Four probing pin probe includes cylinder, cover, be provided with in the cavity that cylinder and cover are formed cone seat, probe, helical spring, spring base, guide posts, guiding column base, voltage regulation screw, on fairlead, lower fairlead, described guiding column base is arranged on cone seat, guide and column base is fixedly installed several guide posts, spring base is provided with several and guides through hole, and guide posts is each passed through this and guides through hole, and spring base can slide in guide posts；Upper fairlead and lower fairlead are respectively arranged at the two ends up and down of cone seat, and 4 probes are stitched together by metal capillary with corresponding helical spring after being each passed through fairlead and lower fairlead, and every helical spring afterbody is each attached on spring base；Cover is fixed on cylinder, and voltage regulation screw is pressed on spring base after cover, and spinning in and out are with the pressure of adjustable screw spring.Changed the position of spring base by voltage regulation screw, the pressure of every helical spring can be changed, thus realizing the adjustment to probe pressure.
Further, the probe of described ruby Four probing pin probe is Talide probe, needle point radius of curvature is in 25 μm of-900 μ m, every probe is stitched together by capillary tube with every helical spring, probe, metal capillary and helical spring constitute an independent spring probe system, and the pressure limit of each spring probe system is between 25-250g.
Preferably, the voltage regulation limits of described test voltage actuator is in 5V-80V.Thus preventing the overtension between 1,4 probe two needle points, layer material to be measured is produced electric breakdown phenomena, damaged material.
A kind of method of testing based on above-mentioned FOUR-POINT PROBE METER, comprises the following steps:
(1) open host power supply, first pass through test voltage actuator and regulate the test voltage between two outer probes；Then regulate cantilever position, make four probes of ruby Four probing pin probe press completely and touch on layer material surface to be measured；
(2) switch switch open constant-current source circuit by constant-current source break-make, and select suitable current value；
(3) voltage detecting circuit in Measurement and Control System detects the voltage in four probes between two probes of inner side, and magnitude of voltage is sent to processing module, magnitude of voltage is converted into square resistance by processing module, and square resistance is done the automatic correction of temperature, diameter, probe spacing error, finally export measurement result.
The present invention compared with prior art, has the advantage that and beneficial effect:
1, current domestic existing four-point probe, generally can only regulate the test electric current of sample, and constant-current source does not set on and off switch, it is easy to electric breakdown phenomena occurs.The present invention is by arranging test voltage actuator, constant-current source break-make switching switch, both scalable sample test electric current, can also adjust the test voltage of 1,4 probes, appropriate voltage can be connected again after probe contacts layer material, ensure will not occur air ionization (puncturing) when probe is close to tested layer material, and making the voltage being added on tested print will not at contact place attacking material, safety in utilization is higher.Can be widely applied for the Square resistance measurement of the emerging functional materials such as flat-panel screens, lithium battery polar plate, ITO touch screen, metal-oxide, semiconductor lamella (epitaxial layer, ion implanted layer, diffusion layer), camouflage coating, nano coating, ultrathin metallic film, flexible shielding film.
2, current domestic conventional probe is epoxy resin or engineering plastics are made, there is the shortcoming that material is not wear-resisting, affected by environment greatly, precision is poor, general single probe pressure changes in the narrower range of 125-200g, 300-400g, it is difficult to accomplish below 100g.Present invention employs ruby Four probing pin probe, owing to this Four probing pin probe pin external diameter precisely coordinates with gem sleeve diameter, therefore probe pressure can 25-250g in a big way in change, particularly every pin pressure is minimum accomplishes 25g, can cause layer material to press and wear or the problem of mechanical damage of pressure break by significantly less probe itself.
3, the probe tip radius of curvature used by the present invention can change to 900 μm from 25 μm according to actual needs, and the probe radius of curvature of domestic existing Four probing pin probe is generally fixed between 50-80 μm.Thickness is changed to the layer material of 100 μm from 3nm, mechanical strength differs greatly, the probe minimum pressure of present invention design is up to 25g, needle point maximum curvature radius can to 900 μm, therefore the combination of probe radius of curvature more preferably and pressure can be chosen in actual applications, to ensure layer material will not produce mechanical damage in testing, and there is stable measurement signal.
Accompanying drawing explanation
Fig. 1 is the test philosophy schematic diagram of the present invention；
Fig. 2 is human-computer interaction interface schematic appearance on main frame casing of the present invention；
Fig. 3 is testing jig structural representation of the present invention；
Fig. 4 is ruby Four probing pin probe perspective view of the present invention；
Fig. 5 is the sectional view of ruby Four probing pin probe shown in Fig. 4；
Fig. 6 is the structure principle chart of test voltage actuator in the present invention.
Wherein, 1-voltage regulation screw；2-cover；3-cylinder；4-metal capillary；The upper fairlead of 5-；Fairlead under 6-；7-guides column base；8-spring base；9-probe；10-bores seat；11-helical spring；12-guide posts；13-cantilever；14-sample stage；15-column；16-base plate.
Detailed description of the invention
Below in conjunction with embodiment and accompanying drawing, the present invention is described in further detail, but embodiments of the present invention are not limited to this.
Embodiment 1
As shown in Figure 1, layer material is carried out the FOUR-POINT PROBE METER of nondestructive measurement by the present embodiment, including main frame, ruby Four probing pin probe, testing jig, Measurement and Control System, described main frame includes casing and test circuit, and power circuit and constant-current source circuit in test circuit are arranged in casing.Ruby Four probing pin probe includes 1,2,3,4 four probes, and wherein 1,4 probes are outer probe, and 2,3 probes are internal probe.As shown in Figure 6, test voltage actuator includes a potentiometer, and in the present embodiment, this potentiometer one end is connected with power circuit, and the other end is connected with one of them outer probe (1 probe).Constant-current source break-make switching switch is arranged between constant-current source circuit and Four probing pin probe.Measurement and Control System includes voltage detecting circuit and processing module, and ruby Four probing pin probe is connected with voltage detecting circuit.
As shown in Figure 2, the adjusting knob (being marked with the knob of " test voltage ") of test voltage actuator and constant-current source break-make switching switch (being marked with the button of " constant-current source ") are arranged on the human-computer interaction interface on main frame casing, human-computer interaction interface is additionally provided with several display screens, it is respectively used to show the current value of current setting, test voltage value and square resistance/resistivity value that last computation and measurement obtains.
As shown in Figure 3, described testing jig includes cantilever 13, sample stage 14, column 15, base plate 16, sample stage 14 is used for place layer material to be measured, sample stage 14 is positioned on base plate 16, cantilever 13 is fixed on the side of base plate 16 by column 15, in one end of cantilever 13, ruby Four probing pin probe is installed, ruby Four probing pin probe central axis and sample stage 14 center centering, cantilever 13 can oscilaltion on column, ruby Four probing pin probe and main frame link together by having the quad line of shielding action.
As shown in Figure 4,5, in the present embodiment, ruby Four probing pin probe includes cone seat 10, cylinder 3, cover 2, probe 9, helical spring 11, spring base 8, guide posts 12, guides column base 7, voltage regulation screw 1, metal capillary 4, upper fairlead 5, lower fairlead 6.Described guiding column base 7 is arranged on cone seat 10, and guide posts 12 one end is fixed on guiding column base 7, and guide posts 12 is through four guidings through hole (can increase and decrease according to practical application) of spring base 8, and spring base 8 can move swimmingly along guide posts about 12；The described probe 9 upper fairlead 5 of traverse and lower fairlead 6, it is stitched together by metal capillary 4 and helical spring 11, each helical spring 11 afterbody is each attached on spring base 8, cover 2 is fixed on cylinder 3, voltage regulation screw 1 is pressed on spring base 8 after cover 2, spinning in and out voltage regulation screw 1, can change the relative position of spring base 8, thus realizing the adjustment to four probe pressure.
Probe 9 in the present embodiment is 4 Talide probes, and its needle point radius of curvature passes through grinding technology, can accomplish in 25 μm of-900 μ m.Every probe is stitched together by capillary tube and helical spring and constitutes independent spring system, and the pressure regulation spectrum of helical spring is wide, the life-span is long, and the pressure of every probe can regulate within the scope of 25-250g.For the layer material of different size, while guaranteeing measurement result, can farthest ensure that it is not subject to crushing.
A kind of method of testing based on above-mentioned FOUR-POINT PROBE METER, comprises the following steps:
(1) open host power supply, first pass through test voltage actuator and regulate the test voltage between two outer probes；Then regulate the lifting handle on testing jig cantilever, make four probes of ruby Four probing pin probe press completely and touch on layer material surface to be measured；
(2) switch switch open constant-current source circuit by constant-current source break-make, and select suitable current value；
(3) voltage detecting circuit in Measurement and Control System detects the voltage in four probes between two probes of inner side, and magnitude of voltage is sent to processing module, magnitude of voltage is converted into square resistance by processing module, and square resistance is done the automatic correction of temperature, diameter, probe spacing error, finally export measurement result.
Above-described embodiment is the present invention preferably embodiment; but embodiments of the present invention are also not restricted to the described embodiments; the change made under other any spirit without departing from the present invention and principle, modification, replacement, combination, simplification; all should be the substitute mode of equivalence, be included within protection scope of the present invention.
Claims (6)
1. pair layer material carries out the FOUR-POINT PROBE METER of nondestructive measurement, including Four probing pin probe, testing jig, main frame, Measurement and Control System, constant-current source circuit and power circuit is included in main frame, it is characterized in that, FOUR-POINT PROBE METER also includes test voltage actuator, test voltage actuator is arranged between power circuit and Four probing pin probe, for regulating in Four probing pin probe the test voltage between two outer probes before the test begins；
Described FOUR-POINT PROBE METER also includes constant-current source break-make switching switch, and constant-current source break-make switching switch is arranged between constant-current source circuit and Four probing pin probe, is used for controlling to press to touch completely at probe tip just to connect constant-current source circuit behind layer material surface；
Described Four probing pin probe is ruby Four probing pin probe, is connected with main frame by having the quad line of function of shielding；
Described ruby Four probing pin probe includes cylinder, cover, be provided with in the cavity that cylinder and cover are formed cone seat, probe, helical spring, spring base, guide posts, guiding column base, voltage regulation screw, on fairlead, lower fairlead, described guiding column base is arranged on cone seat, guide and column base is fixedly installed several guide posts, spring base is provided with several and guides through hole, guide posts is each passed through this and guides through hole, and spring base can slide in guide posts；Upper fairlead and lower fairlead are respectively arranged at the two ends up and down of cone seat, and 4 probes are stitched together by metal capillary with corresponding helical spring after being each passed through fairlead and lower fairlead, and every helical spring afterbody is each attached on spring base；Cover is fixed on cylinder, and voltage regulation screw is pressed on spring base after cover, and spinning in and out are with the pressure of adjustable screw spring.
2. the FOUR-POINT PROBE METER that layer material is carried out nondestructive measurement according to claim 1, it is characterized in that, the casing of described main frame is provided with human-computer interaction interface, test voltage actuator adjusting knob and constant-current source break-make switching switch are respectively provided with on the surface, also being provided with display screen on this interface, display screen is for externally showing parameter and the measurement result of each parts of current setting simultaneously.
3. the FOUR-POINT PROBE METER that layer material is carried out nondestructive measurement according to claim 1, it is characterized in that, the probe of described ruby Four probing pin probe is Talide probe, needle point radius of curvature is in 25 μm of-900 μ m, every probe is stitched together by capillary tube with every helical spring, probe, metal capillary and helical spring constitute an independent spring probe system, and the pressure limit of each spring probe system is between 25-250g.
4. the FOUR-POINT PROBE METER that layer material is carried out nondestructive measurement according to claim 1, it is characterised in that the voltage regulation limits of described test voltage actuator is in 5V-80V.
5. the FOUR-POINT PROBE METER that layer material carries out nondestructive measurement according to claim 1, it is characterised in that described test voltage actuator includes a potentiometer, this potentiometer one end is connected with power circuit, and the other end is connected with one of them outer probe.
6. the method for testing based on FOUR-POINT PROBE METER described in any one of claim 1-5, it is characterised in that comprise the following steps:
(1) open host power supply, first pass through test voltage actuator and regulate the test voltage between two outer probes；Then regulate cantilever position, make four probes of ruby Four probing pin probe press completely and touch on layer material surface to be measured；
(2) switch switch open constant-current source circuit by constant-current source break-make, and select suitable current value；
(3) voltage detecting circuit in Measurement and Control System detects the voltage in four probes between two probes of inner side, and magnitude of voltage is sent to processing module, magnitude of voltage is converted into square resistance by processing module, and square resistance is done the automatic correction of temperature, diameter, probe spacing error, finally export measurement result.
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| CN104880436B (en) * | 2015-04-30 | 2017-09-05 | 华侨大学 | A kind of thin film high temperature photoelectricity physical property testing device |
| CN104849558B (en) * | 2015-05-28 | 2018-01-16 | 东莞华贝电子科技有限公司 | Impedance measures component, impedance measuring equipment and impedance method for measurement |
| CN106041343B (en) * | 2016-07-02 | 2018-03-30 | 北京工业大学 | A kind of method for being used to monitor the change of solder bonding metal connection resistance on-line |
| CN109444551B (en) * | 2018-09-10 | 2020-09-15 | 全球能源互联网研究院有限公司 | Method and circuit for testing square resistance of semiconductor |
| CN109738702A (en) * | 2019-03-13 | 2019-05-10 | 江苏省特种设备安全监督检验研究院 | Probe, probe and the measuring instrument of the square resistance of nondestructive measurement graphene film |
| CN111596154B (en) * | 2020-05-18 | 2023-01-03 | 哈尔滨工业大学 | Auxiliary clamp for testing temperature-changing electrical property of small sample |
| CN114252003A (en) * | 2021-12-09 | 2022-03-29 | 广州昆德半导体测试技术有限公司 | Copper foil thickness measuring probe and probe head thereof |
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| US4491797A (en) * | 1982-06-01 | 1985-01-01 | Northern Telecom Limited | Test contact resistance of dry circuit contacts |
| CN201281729Y (en) * | 2008-09-11 | 2009-07-29 | 中国北车集团大同电力机车有限责任公司 | Grounding resistance tester |
| CN101881742B (en) * | 2010-07-21 | 2011-09-14 | 中国地质大学（武汉） | Device for measuring multi-passage heat conductivity |
| CN102539927A (en) * | 2011-12-14 | 2012-07-04 | 东华大学 | Method for measuring temperature-controllable four-probe square resistance and resistivity |
| CN202794494U (en) * | 2012-09-28 | 2013-03-13 | 贵州航天计量测试技术研究所 | Device for four-point probe resistivity tester verification |
| CN103197147B (en) * | 2013-03-28 | 2015-10-28 | 顺德中山大学太阳能研究院 | A kind of multi-functional contact resistance automatic measuring instrument of solar cell and measuring system thereof |
| CN203479907U (en) * | 2013-09-23 | 2014-03-12 | 广州市昆德科技有限公司 | Square resistance tester allowing nondestructive measurement to be performed on thin-layered materials |
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