A super small kelly gap super hard alloy head test piece

Abstract

The present application relates to the technical field of test piece, in particular to a superhard alloy head test piece with super-small Kelvin gap. It comprises two metal test pieces, and superhard alloy heads are embedded in the two metal test pieces. In the present application, the super-small Kelvin gap with a size of 0.015 mm and the isolation design of the insulating layer can effectively separate the current and voltage transmission paths, accurately eliminate the interference of the wire resistance and the contact resistance on the measurement results, meet the high-precision requirement of the super-small pin in the precision test, and the superhard alloy heads are embedded in the special-shaped grooves of the metal test pieces, the high hardness of more than 70HRC and the high-temperature resistance of more than 1000 DEG C are utilized to significantly reduce the ablation loss of the metal test piece during use, even in high-frequency test or high-temperature environment, the stable contact of the first contact head and the second contact head with the measured object can be ensured, the reliability of the contact performance is maintained, and the service life of the test piece is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of test pieces, in particular to a super-hard alloy head test piece with an ultra-small Kelvin gap. BACKGROUND

[0002] In the production of semiconductor elements, performance parameters often need to be tested and separated, and test pieces play an important role in connecting test materials and test machines. Whether the performance of the test piece is good will directly affect the production efficiency, product quality and production cost.

[0003] In the research and production process of semiconductor, microelectronic and precision electronic devices, high-precision testing of electrical parameters of ultra-small pins is a key link to ensure product performance and reliability. Traditional testing methods use double-line measurement, and current and voltage signals share the transmission line. Wire resistance and contact resistance will significantly affect the measurement results, making it difficult to meet the needs of advanced process chips, high-density packaged devices (such as BGA, Flip Chip) and other micro-nano scale products. When the pin pitch is reduced to microns, the error caused by contact resistance and parasitic effects is more prominent, making it difficult to accurately measure device resistance, voltage and other parameters.

[0004] In addition, the existing test piece is prone to wear and ablation at the contact part with the pin under high-frequency use or high-temperature and high-load test environment, resulting in decreased contact performance and inaccurate test data. Ordinary metal test pieces are prone to surface wear during repeated friction, causing increased contact resistance, unstable signal transmission and other problems. In high-temperature environments, the test piece material may deform or oxidize, further affecting test reliability, shortening the service life of the test piece, and increasing test cost and maintenance burden. In view of this, we propose a super-hard alloy head test piece with an ultra-small Kelvin gap. SUMMARY

[0005] The present application aims to provide a super-hard alloy head test piece with an ultra-small Kelvin gap to solve the problem of traditional double-line measurement in the background art, which is difficult to accurately measure micro-nano scale product parameters due to wire and contact resistance. The existing test piece is prone to wear and ablation under high-frequency or high-temperature conditions, resulting in poor contact performance, short service life and increased test cost.

[0006] To achieve the above-mentioned purpose, the present application provides a super-hard alloy head test piece with an ultra-small Kelvin gap, comprising two metal test pieces, both of which are embedded with super-hard alloy heads. One side of one of the metal test pieces is coated with an insulating layer. The metal test piece with the insulating layer is arranged in parallel with the metal test piece without the insulating layer, forming a Kelvin combination.

[0007] One end of the two metal test pieces is fixedly connected with a current pin and a voltage pin respectively, the current pin and the voltage pin are isolated by an insulating layer, forming a Kelvin gap, to adapt to the precise test requirement of the ultra-small pin; the superhard alloy head is used to reduce the ablation loss of the metal test piece in the use process, and ensure the stability and reliability of the contact performance.

[0008] The beneficial effects of the present application are:

[0009] 1、In the present application, through the isolation design of 0.015mm ultra-small Kelvin gap and insulating layer, the current and voltage transmission paths can be effectively separated, the interference of wire resistance and contact resistance on the measurement result can be accurately eliminated, the high precision requirement of ultra-small pin in precise test can be met, and the superhard alloy head is embedded in the special-shaped groove of the metal test piece, the high hardness of more than 70HRC and the high temperature resistance performance of more than 1000 DEG C are utilized, the ablation loss of the metal test piece in the use process is significantly reduced, even in high frequency test or high temperature environment, the stable contact of the first contact head and the second contact head with the measured object can be ensured, the reliability of the contact performance can be maintained, and the service life of the test piece can be prolonged.

[0010] 2、In the present application, the insulating layer is divided into a first coating layer suitable for the superhard alloy head and a second coating layer suitable for the metal test piece, the layered design can effectively prevent short circuit between the current pin and the voltage pin, inhibit parasitic capacitance and electromagnetic interference, further improve the reliability of the test result, and make it suitable for semiconductor, precise electronic component detection and other scenes with high requirements on insulation and signal stability.

[0011] As a further improvement of the technical solution, the two metal test pieces are provided with special-shaped grooves for installing the superhard alloy head, the superhard alloy head is located in the special-shaped groove, the two sides of the superhard alloy head are provided with protruding blocks, the protruding blocks are matched with the recesses on the special-shaped groove, and the special-shaped groove is matched with the superhard alloy head.

[0012] The beneficial effects of the above further scheme are that the protruding blocks on the two sides of the superhard alloy head are tightly matched with the recesses of the special-shaped groove, forming a mortise and tenon structure embedding, limiting the horizontal, vertical displacement and rotation of the alloy head on the metal test piece, ensuring that the alloy head will not loosen or fall off in the test process due to external force (such as plugging, vibration), protecting the stability of the whole structure of the test piece, and making the measurement process stable and reliable.

[0013] As a further improvement of the present technical solution, the top of the two metal test pieces near one end of the super-hard alloy head are respectively fixedly connected with a first contact head and a second contact head, the Kelvin gap is located between the first contact head and the second contact head, the tops of the first contact head and the second contact head are both arc-shaped, used to contact the object to be measured, and the first contact head and the second contact head are located on one side of the super-hard alloy head.

[0014] The beneficial effect of adopting the above further solution is that the arc-shaped design of the first contact head and the second contact head increases the contact area with the object to be measured, can better fit the objects to be measured with different surface morphologies, and improves the adaptability of the test piece to various types of objects to be measured.

[0015] As a further improvement of the present technical solution, the insulating layer is divided into a first coating and a second coating, both of which are located between two metal test pieces, the first coating is adapted to the super-hard alloy head, and the second coating is adapted to the metal test piece.

[0016] The beneficial effect of adopting the above-mentioned further scheme is that the first coating fits tightly to the super-hard alloy head, preventing the alloy head from causing short circuit between adjacent metal test pieces or pins due to its conductive properties, ensuring that the signal transmission paths of the current pin and the voltage pin do not interfere with each other; the second coating covers the surface of the metal test piece, further isolating the non-contact areas of the two test pieces, avoiding accidental conduction due to spacing fluctuations.

[0017] As a further improvement of the present technical solution, a gap is left between the current pin and the voltage pin, and the current pin and the voltage pin have the same shape. The Kelvin gap between the current pin and the voltage pin is 0.015 mm, which is used to adapt to small pins. The metal test piece is located above the current pin and the voltage pin and has two circular holes for installing the metal test piece.

[0018] The beneficial effect of adopting the above-mentioned further solution is that the ultra-small Kelvin gap of 0.015mm accurately adapts to small pins, separates the current and voltage paths, avoids interference from wire resistance and contact resistance, and ensures high precision when measuring parameters such as resistance and voltage of ultra-small pins; pins of the same shape ensure symmetrical distribution on both sides of the pin, so that the current injection point and the voltage detection point are strictly aligned, reducing the internal resistance voltage divider error of the measured pin.

[0019] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure assembly of the present invention;

[0021] Figure 2 For the present invention Figure 1 Schematic diagram at point A in the middle;

[0022] Figure 3 This is a schematic diagram of the overall disassembly of the present invention;

[0023] Figure 4 Schematic diagram of the insulating layer of the present invention;

[0024] Figure 5 For the present invention Figure 4 Schematic diagram at point B in the middle.

[0025] The meaning of each number in the figure is:

[0026] 100. Metal test piece;

[0027] 200, super-hard alloy head; 201, first contact head; 202, second contact head;

[0028] 300, insulating layer; 301, first coating layer; 302, second coating layer;

[0029] 400, current pin;

[0030] 500, voltage pin;

[0031] 600. Kelvin gap. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0033] The present invention provides the following preferred embodiments

[0034] See also Figures 1-5 As shown, this embodiment provides a super-hard alloy head test piece with an ultra-small Kelvin gap, comprising two metal test pieces 100, each of which is embedded with a super-hard alloy head 200. One side of one of the metal test pieces 100 is coated with an insulating layer 300, and the metal test piece 100 coated with the insulating layer 300 and the metal test piece 100 not coated with the insulating layer 300 are stacked in parallel to form a Kelvin combination;

[0035] One end of the two metal test pieces 100 is fixedly connected with a current pin 400 and a voltage pin 500, respectively, and the current pin 400 and the voltage pin 500 are isolated by an insulating layer 300 to form a Kelvin gap 600, so as to adapt to the precise test requirement of the ultra-small pin; and the superhard alloy head 200 is used to reduce the ablation loss of the metal test piece 100 in the use process and ensure the stability and reliability of the contact performance.

[0036] The insulating layer 300 can adopt a high-wear-resistance epoxy resin macromolecular insulating glue, a non-conductive glue with a manufacturer number of Loctite ABLESTIK NCA 5836, and 30wt% AlN fillers, a thermal conductivity of 1.2W / mK, a surface roughness Ra<0.8μm (ISO 4287) after curing, and a thickness tolerance of ±1μm, which can ensure the geometric accuracy of the ultra-small Kelvin gap, and the insulating layer 300 is not easy to flow during curing, so as to avoid the risk of short circuit caused by edge thickening.

[0037] When the test probe or pin is repeatedly slid / pressed (such as high-frequency contact in the automatic test equipment ATE), the fillers can reduce the friction coefficient and avoid the short circuit of the metal test piece 100 after the abrasion of the insulating layer.

[0038] Therefore, based on the above features, the improvement points of the present application are described in detail:

[0039] The traditional Kelvin test piece is arranged in front and back, and a sufficient safety gap needs to be left between the current pin 400 and the voltage pin 500 to prevent short circuit. When facing small-size pins, the pin tip is extremely likely to exceed the pin area, causing poor contact. In addition, the current pin 400 and the voltage pin 500 cannot be completely consistent in the mechanical structure, the contact force is unbalanced, and the long-term reliability is affected. Therefore, the insulating layer 300 is brushed on one side between the current pin 400 and the voltage pin 500, thereby forming an ultra-small Kelvin gap 600. On the one hand, the Kelvin gap 600 occupies a small space and can be used for contact of ultra-small pins. In the extremely small physical space, the electrical isolation of the current path and the voltage detection path is realized, the interference of the wire resistance and the contact resistance on the measurement result is avoided, so as to ensure the high-precision measurement of the resistance, voltage and other parameters of the ultra-small pin, and the Kelvin gap 600 is especially suitable for precise test in the space-limited scene of semiconductor micro-nano devices, high-density integrated chips and the like.

[0040] On the other hand, because the current pin 400 and the voltage pin 500 are arranged in parallel, their structures are almost completely consistent, have the same mechanical and electrical properties, and make the contact more stable and reliable.

[0041] Since traditional Kelvin test pieces are usually made of a single conductive material, although they have certain wear resistance, their contact surfaces are easily worn during frequent tests, resulting in a decrease in contact quality. Especially in high current tests, since the contact part between the test piece and the chip will generate high temperature, conventional conductive materials such as beryllium copper have low heat resistance and are prone to burning and contact degradation. Therefore, the super-hard alloy head 200 designed to be embedded in the metal test piece 100, with its extremely high hardness of more than 70HRC, can withstand repeated mechanical friction in the test, significantly reduce wear, extend the service life of the test piece and improve the reliability of long-term testing; at the same time, it can still maintain good mechanical properties in high temperature environments above 1000°C, which can effectively reduce test piece burning, stabilize contact performance, and ensure the accuracy and stability of tests in high temperature environments. It is especially suitable for high-frequency testing, high-temperature working conditions or scenarios with high wear resistance requirements.

[0042] On the basis of the above, the specific structure is disclosed in detail:

[0043] To achieve the connection between the super-hard alloy head 200 and the metal test piece 100, the two metal test pieces 100 are disclosed in detail, such as Figure 1 As shown, both metal test pieces 100 are provided with special-shaped grooves for installing super-hard alloy heads 200. The super-hard alloy heads 200 are located inside the special-shaped grooves. Both sides of the super-hard alloy heads 200 are provided with protrusions, and the protrusions are matched with the depressions on the special-shaped grooves. The special-shaped grooves are matched with the super-hard alloy heads 200. Therefore, by matching the special-shaped grooves on the metal test pieces 100 with the super-hard alloy heads 200, the super-hard alloy heads 200 are firmly embedded in the metal test pieces 100, ensuring that the two maintain reliable mechanical connection and electrical conduction during the test process, avoiding problems such as poor contact and signal interruption due to loosening, displacement or falling off, thereby improving the stability and consistency of the test structure, and ensuring the measurement accuracy and reliability in high-frequency tests or complex working conditions such as vibration and high-temperature environments.

[0044] Furthermore, to achieve the measurement of the metal test piece 100, the structure of the metal test piece 100 is further disclosed in detail, such as Figure 1 and Figure 2 As shown, the top of the two metal test pieces 100 near one end of the super-hard alloy head 200 are respectively fixedly connected with the first contact head 201 and the second contact head 202, and the Kelvin gap 600 is located between the first contact head 201 and the second contact head 202. The tops of the first contact head 201 and the second contact head 202 are both arc-shaped, which are used to contact the object to be measured, and the first contact head 201 and the second contact head 202 are located on one side of the super-hard alloy head 200. Therefore, the arc shape of the top of the contact head can increase the contact area with the object to be measured, and at the same time adapt to the slight undulations on the surface of the object to be measured through elastic deformation, thereby reducing poor contact caused by surface roughness or position deviation.

[0045] However, to achieve the installation of the insulating layer 300, specifically as Figures 3-5 As shown, the insulating layer 300 is divided into a first coating 301 and a second coating 302. The first coating 301 and the second coating 302 are both located between the two metal test pieces 100. The first coating 301 is adapted to the super-hard alloy head 200, and the second coating 302 is adapted to the metal test piece 100. The super-hard alloy head 200 serves as a key node for current or voltage transmission. The first coating 301 on its surface can electrically isolate adjacent metal test pieces 100 or other conductors to avoid direct conduction of the current path and the voltage detection path near the alloy head; the main body of the metal test piece 100 is usually a conductive material, and the second coating 302 can isolate the non-contact area between the two test pieces to avoid accidental conduction due to fluctuations in the spacing when the test pieces are stacked in parallel.

[0046] Next, the metal test piece 100 needs to be connected to the external device, as shown in the following example: Figure 3 As shown, there is a gap between the current pin 400 and the voltage pin 500, and the current pin 400 and the voltage pin 500 have the same shape. The Kelvin gap 600 between the current pin 400 and the voltage pin 500 is 0.015 mm, which is used to adapt to small pins. The metal test piece 100 is located above the current pin 400 and the voltage pin 500 and has two circular holes for mounting the metal test piece 100. The 0.015 mm gap can accurately match ultra-small pins such as fan-out pins and FlipChip solder balls in advanced semiconductor packages. Their size is close to the characteristic line width in the integrated circuit process, meeting the testing requirements of nano-scale devices; the current pin and the voltage pin 500 have the same shape, ensuring that the two are symmetrically distributed on both sides of the pin, so that the current injection point and the voltage detection point are strictly aligned, reducing the voltage divider error of the internal resistance of the tested pin. When measuring the resistance of nanowires, the symmetrical pin layout can avoid measurement deviation caused by position offset.

[0047] Working steps of the present invention:

[0048] This test piece is based on the Kelvin four-wire method principle. A Kelvin combination is formed by stacking two metal test pieces 100 in parallel. The current pin 400 and the voltage pin 500 are isolated by an insulating layer 300 to construct an ultra-small Kelvin gap 600 of 0.015mm, realizing electrical separation of the current path and the voltage detection path. During the test, the current pin 400 is connected to the power supply to provide a constant current to the object under test; the voltage pin 500 is connected to a high-impedance measuring instrument to detect the actual voltage at both ends of the object under test. The super-hard alloy head 200 is embedded in the special-shaped groove of the metal test piece 100. With its high hardness and high temperature resistance, it supports the stable contact between the arc-shaped first and second contact heads and the object under test, ensuring stable current injection and accurate transmission of voltage signals. The double-layer coating of the insulating layer 300 is respectively adapted to the gold head and the metal sheet to prevent short circuit between the pins; the metal sheet is fixed above the pin through a circular hole to maintain the stability of the gap size and ensure measurement accuracy.

[0049] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A superhard alloy head test piece with an ultra-small Kelvin gap, comprising two metal test pieces (100), characterized in that: Both metal test pieces (100) are embedded with a superhard alloy head (200), one side of one of the metal test pieces (100) is coated with an insulating layer (300), and the metal test piece (100) coated with the insulating layer (300) and the metal test piece (100) not coated with the insulating layer (300) are stacked in parallel to form a Kelvin combination; One end of the two metal test pieces (100) is fixedly connected to a current pin (400) and a voltage pin (500), respectively. The current pin (400) and the voltage pin (500) are separated by an insulating layer (300) to form a Kelvin gap (600) to meet the precision testing requirements of ultra-small pins. The super-hard alloy head (200) is used to reduce the ablation loss of the metal test piece (100) during use and ensure the stability and reliability of its contact performance. The Kelvin gap between the current pin (400) and the voltage pin (500) is 0.015 mm, which is used to adapt to small pins; The insulating layer (300) is divided into a first coating layer (301) and a second coating layer (302), and the first coating layer (301) and the second coating layer (302) are both located between two metal test pieces (100); The first coating (301) is compatible with the superhard alloy head (200), and the second coating (302) is compatible with the metal test piece (100).

2. The ultra-small Kelvin gap super-hard alloy head test piece according to claim 1, characterized in that: Both metal test pieces (100) are provided with special-shaped grooves for mounting a super-hard alloy head (200), wherein the super-hard alloy head (200) is located inside the special-shaped grooves.

3. The ultra-small Kelvin gap super-hard alloy head test piece according to claim 1, characterized in that: The tops of the two metal test pieces (100) close to one end of the superhard alloy head (200) are respectively fixedly connected with a first contact head (201) and a second contact head (202), and the Kelvin gap (600) is located between the first contact head (201) and the second contact head (202).

4. The ultra-small Kelvin gap super-hard alloy head test piece according to claim 3, characterized in that: The tops of the first contact head (201) and the second contact head (202) are both arc-shaped and are used to contact the object to be measured, and the first contact head (201) and the second contact head (202) are located on one side of the superhard alloy head (200).

5. The ultra-small Kelvin gap super-hard alloy head test piece according to claim 1, characterized in that: A gap is left between the current pin (400) and the voltage pin (500), and the current pin (400) and the voltage pin (500) have the same shape.

6. The ultra-small Kelvin gap super-hard alloy head test piece according to claim 1, characterized in that: The metal test piece (100) is located above the current pin (400) and the voltage pin (500) and has two circular holes for mounting the metal test piece (100).

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