Tip structure for suppressing radiation, two-dimensional probe and probe structure

Abstract

The present invention relates to the technical field of microwave radio frequency test. Disclosed are a tip structure for suppressing radiation, a two-dimensional probe and a probe structure. For the problems in millimeter-wave to terahertz on-chip testing of serious high-frequency radiation leakage, difficulty in continuous matching between impedance and broadband, mutual interference between a direct-current bias path and a radio frequency channel, poor balance of differential measurement, and the like, a cantilever shielding layer is introduced into a tip structure to construct a quasi-TEM transmission environment, thereby suppressing high-frequency radiation at source; a rectangular micro-coaxial structure, a rectangular waveguide-to-circular coaxial conversion structure, and an integrated direct-current bias network that are realized in light of additive manufacturing improve impedance continuity and structural consistency in a high-frequency band; and on this basis, a dual-band two-dimensional probe integrated with a duplexer, a differential two-dimensional probe suitable for differential measurement and a closed probe are further provided, so that a test system realizes single-ended and differential on-chip testing having high isolation, high repeatability and high precision in an ultra-wide frequency range.

Description

A radiation-suppressing tip structure, a two-dimensional probe, and a probe structure. Technical Field

[0001] This invention belongs to the field of microwave radio frequency testing technology, and particularly relates to a radiation-suppressing tip structure, a two-dimensional probe, and a probe structure. Background Technology

[0002] In on-chip testing in the millimeter-wave to terahertz frequency band (110 GHz to 1.1 THz), as integrated circuits and high-frequency systems evolve towards higher frequencies, larger bandwidths, and greater complexity, existing probe structures are gradually revealing significant bottlenecks in electromagnetic performance, fabrication accuracy, and functional integration capabilities. When the test frequency exceeds 110 GHz, especially in the range above 200 GHz, the coupling between the radiation field near the probe tip and the adjacent metal is significantly enhanced, often leading to abnormal positive insertion loss or amplitude drift after on-chip calibration (a deviation ≥0.5 dB is considered to affect test accuracy, and ≥1 dB will cause a failure error), compromising calibration effectiveness and affecting measurement reliability. Simultaneously, traditional three-dimensional metal probes, limited by the minimum linewidth of additive manufacturing processes (50–100 μm), struggle to meet the requirements for tip geometric accuracy and impedance continuity in frequency bands above 500 GHz, easily resulting in impedance mismatch, high-frequency mode leakage, and signal integrity degradation.

[0003] Furthermore, as terahertz on-chip measurement systems evolve towards higher functional density and greater adaptability to various scenarios, existing probe structures still face the following three types of scalability limitations:

[0004] First, the DC bias function is difficult to be compatible with high-frequency paths. When testing active devices such as high-power amplifiers and mixers, an independent DC bias channel is often required. However, existing ultra-high frequency probes generally lack a DC lead structure with high isolation, low parasitics, and stable operation, which easily introduces parasitic inductance / capacitance in the terahertz band, affecting calibration and measurement accuracy.

[0005] Secondly, it is difficult to meet the testing requirements of multiple frequency bands or spanning multiple octaves. Future testing needs are gradually evolving from "single frequency point" to "continuous measurement across frequency bands," such as a dual-band combination of DC-110GHz + 110-170GHz. However, existing probes lack structures that can utilize duplexers or multiplexers to achieve frequency splicing and passband isolation, making it difficult for the same probe to cover multiple high-frequency bands, resulting in non-reusable test links and increased equipment costs and system complexity.

[0006] Third, there is a lack of differential capability for coaxial / waveguide probes. Due to the rapid increase in the number of terahertz differential devices, test platforms urgently need coaxial differential probes and waveguide differential probes to accurately obtain the differential-mode link response of differential devices such as terahertz balanced amplifiers, differential couplers, and balanced mixers.

[0007] Scholars and research teams have proposed a series of improvement schemes. For example, patent CN113960338A proposes a micro-coaxial RF probe based on multi-material additive manufacturing. By achieving efficient conversion between GSG tips (with three probes, the middle one being an S-type probe, and the two sides of the S-type probe being G-type probes, where G stands for Ground and S stands for Signal), rectangular micro-coaxial lines, and waveguides, it improves RF performance and processing flexibility. However, its tip mechanical properties are still limited, and the cost of a single probe is relatively high. Subsequently, patent CN115656580A proposed a copper-nickel composite additive manufacturing scheme based on this, introducing a 1 / 4 wavelength short-circuit stub support structure to improve the mechanical stability of the inner conductor, covering multiple bands including W, D, and G, and effectively reducing volume and cost. However, it mainly focuses on mechanical performance optimization and still has shortcomings in high-frequency radiation suppression and terahertz band expansion. Furthermore, patent CN117686753A proposes a micro-coaxial RF cantilever probe structure. By optimizing the cantilever beam design and chamfer structure of the G-pin and S-pin, it achieves consistency in needle mark depth. An anti-radiation structure is added to the needle tip to improve consistency, extending the applicable frequency band to 220GHz to 325GHz and 330GHz to 500GHz. However, the core of this solution still focuses on improving the mechanical properties and wear resistance of the needle tip; it does not provide a systematic solution for suppressing electromagnetic crosstalk in the terahertz frequency band.

[0008] In summary, existing probe structures have made some progress in terms of processing accuracy, mechanical stability, and partial radiation suppression, but they are still difficult to simultaneously meet the triple requirements of electromagnetic radiation control in the terahertz band, high-frequency test adaptability, and high scalability. Technical issues

[0009] Existing probe structures have made some progress in terms of processing accuracy, mechanical stability and partial radiation suppression, but they are still difficult to meet the triple requirements of electromagnetic radiation control in the terahertz band, high-frequency test adaptability and high scalability at the same time. Technical solutions

[0010] To address the aforementioned problems and achieve the aforementioned objectives, this invention provides a radiation-suppressing tip structure, a two-dimensional probe, and a probe structure, aiming to systematically solve the problems of high-frequency radiation crosstalk, terahertz band adaptation, and differential device measurement.

[0011] To achieve the above objectives, in a first aspect, the present invention provides a radiation-suppressing needle tip structure, comprising a ground wire and a signal line, wherein the ground wire is located on both sides of the signal line to form a GSG needle tip structure, and a support structure is provided between the ground wire and the signal line; a cantilevered shielding layer is provided above the ground wire, and a G-needle root hollowing structure is formed in the cantilevered shielding layer near the root of the GSG needle tip structure; both the ground wire and the signal line include a lower nickel layer of the GSG needle tip structure and an upper copper layer of the GSG needle tip structure, and a transition structure is provided at the tip of the ground wire, wherein the thickness of the transition structure gradually decreases from the root of the GSG needle tip structure towards the tip.

[0012] As a further optimization, both the ground wire and the signal wire adopt a cantilever structure.

[0013] As a further optimization, the cantilevered shielding layer is located above the copper layer on the GSG tip structure.

[0014] As a further optimization, the transition structure includes a gradient structure of the lower nickel layer at the GSG tip, a gradient structure between the upper copper layer and the lower nickel layer, and a gradient structure of the upper copper layer at the GSG tip. The gradient structures of the lower nickel layer, the upper copper layer, and the upper copper layer at the GSG tip are all stepped structures.

[0015] As a further optimization, the thickness of the transition structure changes continuously from the root of the GSG needle structure to the tip of the GSG needle structure.

[0016] As a further optimization, at the hollowed-out structure at the root of the G-needle, the ground wire retains the nickel layer under the GSG needle tip structure.

[0017] Secondly, the present invention provides a two-dimensional probe structure, including a tip-to-rectangular coaxial line transition structure, an inner conductor of the rectangular coaxial line, an outer conductor of the rectangular coaxial line, a rectangular coaxial line-rectangular waveguide conversion structure, and the aforementioned tip structure for suppressing radiation; the inner conductor of the rectangular coaxial line is suspended in the outer conductor of the rectangular coaxial line through a support structure; a ground wire is connected to the outer conductor of the rectangular coaxial line, and a signal line is connected to the inner conductor of the rectangular coaxial line through the tip-to-rectangular coaxial line transition structure; the rectangular coaxial line-rectangular waveguide conversion structure includes a rectangular probe and an inner conductor protrusion structure; the rectangular probe is connected to the inner conductor of the rectangular coaxial line through the inner conductor protrusion structure; a waveguide cavity is formed in the outer conductor of the rectangular coaxial line; and the outer side of the rectangular probe is suspended in the waveguide cavity.

[0018] As a further optimization, the width of the transition structure from the tip to the rectangular coaxial line gradually increases from the connection point with the signal line towards the inner conductor of the rectangular coaxial line.

[0019] As a further optimization, the inner conductor of the rectangular coaxial line, the transition structure from the tip to the rectangular coaxial line, the rectangular probe, and the protruding structure of the inner conductor are all made of copper and nickel layers, with the copper layer located above the nickel layer.

[0020] As a further optimization, a DC bias structure is also included. This DC bias structure comprises a low-pass filter and a rectangular coaxial-to-circular coaxial converter, both supported by a support structure. One end of the low-pass filter is connected to the inner conductor of the rectangular coaxial line, and the other end is connected to the rectangular coaxial-to-circular coaxial converter. The low-pass filter includes, in sequence, a first-order resonator, a second-order resonator, a third-order resonator, a fourth-order resonator, and a fifth-order resonator. The first-order, third-order, and fifth-order resonators of the low-pass filter all use high-resistance lines instead of capacitors, while the second-order and fourth-order resonators use open-circuit stub lines instead of parallel inductors.

[0021] Thirdly, the present invention provides a differential two-dimensional probe structure, comprising two aforementioned two-dimensional probe structures arranged mirror-symmetrically along a ground line. Each differential two-dimensional probe structure includes two tip-to-rectangular coaxial line transition structures, two inner conductors of the rectangular coaxial lines, two rectangular coaxial line-to-rectangular waveguide conversion structures, three ground lines, and two signal lines. The two signal lines are respectively connected to the rectangular coaxial line-to-rectangular waveguide conversion structures through the tip-to-rectangular coaxial line transition structures and the inner conductors of the rectangular coaxial lines; all three ground lines are connected to the outer conductors of the rectangular coaxial lines.

[0022] Fourthly, the present invention provides a dual-band two-dimensional probe structure, including a tip-to-rectangular coaxial line transition structure, an inner conductor of the rectangular coaxial line, an outer conductor of the rectangular coaxial line, a rectangular coaxial line-rectangular waveguide conversion structure, a duplexer, a rectangular coaxial-circular coaxial conversion structure, and the aforementioned radiation-suppressing tip structure; the inner conductor of the rectangular coaxial line is suspended in the outer conductor of the rectangular coaxial line through a support structure; a ground wire is connected to the outer conductor of the rectangular coaxial line, and a signal line is connected to the inner conductor of the rectangular coaxial line through the tip-to-rectangular coaxial line transition structure; the rectangular coaxial line-rectangular waveguide conversion structure includes a rectangular probe and an inner conductor protrusion structure, the rectangular probe is connected to the duplexer through the inner conductor protrusion structure, a waveguide cavity is formed in the outer conductor of the rectangular coaxial line, and the outer side of the rectangular probe is suspended in the waveguide cavity; the duplexer includes a high-pass filter, a low-pass filter belonging to the duplexer, and a common terminal, the high-pass filter is connected to the rectangular coaxial line-rectangular waveguide conversion structure, the low-pass filter belonging to the duplexer is connected to the rectangular coaxial-circular coaxial conversion structure, and the common terminal is connected to the radiation-suppressing tip structure through the inner conductor of the rectangular coaxial line. The high-pass filter is based on a first-order resonant structure and uses a coaxial lumped capacitor structure to replace the low-impedance transmission line. The low-pass filter of the duplexer is based on a T-shaped SIR stub-loaded structure, including a first to a fifth resonator connected in sequence. The first, third, and fifth resonators use high-impedance transmission lines, while the second and fourth resonators use a stub-loaded structure to replace the low-impedance transmission line.

[0023] As a further optimization, the coaxial lumped capacitor structure includes a parallel-plate capacitor structure, an upper conductor, a lower conductor, and a rectangular coaxial line outer conductor. The parallel-plate capacitor structure, the upper conductor, and the lower conductor together form the inner conductor, which is set in the rectangular coaxial line outer conductor. The parallel-plate capacitor structure adopts a metal-dielectric-metal stacked arrangement. The two ends of the parallel-plate capacitor structure are respectively connected to the upper conductor and the lower conductor.

[0024] As a further optimization, the coaxial lumped capacitor structure is based on additive manufacturing and includes a three-layer structure. The parallel-plate capacitor structure is located in the second layer, and the outer conductor is located in the first to third layers. The second layer is divided into three layers: layer 2-1, layer 2-2, and layer 2-3. The dielectric of the parallel-plate capacitor structure is located in layer 2-2, the metal is located in layers 2-1 and 2-3, the upper conductor is located in layer 2-3, and the lower conductor is located in layer 2-1. The area of ​​the parallel-plate capacitor structure is proportional to the capacitance value.

[0025] As a further optimization, the coaxial lumped capacitor structure has multiple periodically arranged support structures between the outer and inner conductors of the rectangular coaxial line, located in the 2-2 layer, which are used to support the suspended inner conductor. The dielectric in the parallel plate capacitor structure is the same as the dielectric of the support structures.

[0026] Fifthly, the present invention provides a probe structure, including a waveguide clamp, the waveguide clamp comprising a waveguide clamp base, a first clamping member, a second clamping member, and a connector of optional type. The first clamping member and the second clamping member are both located above the waveguide clamp base and are interconnected. The waveguide clamp base has a probe mounting slot and a positioning through hole. A waveguide resonant cavity is formed on the probe mounting slot, which is used to mount the aforementioned two-dimensional probe structure and dual-band two-dimensional probe structure. The first clamping member has a screw hole and a screw through hole, and the second clamping member has a screw hole and a cylindrical through hole for connecting the connector of optional type. Both the first clamping member and the second clamping member have waveguide channels inside for high-frequency signal output.

[0027] In a sixth aspect, the present invention provides a closed probe structure, comprising a tip-to-rectangular coaxial line transition structure, an inner conductor of the rectangular coaxial line, an outer conductor of the rectangular coaxial line, a matching structure, and the aforementioned tip structure for suppressing radiation; the inner conductor of the rectangular coaxial line is suspended in the outer conductor of the rectangular coaxial line by a support structure; a ground wire is connected to the outer conductor of the rectangular coaxial line, and a signal line is sequentially connected to the inner conductor of the rectangular coaxial line and the matching structure through the tip-to-rectangular coaxial line transition structure; a positioning hole is formed on the outer conductor of the rectangular coaxial line.

[0028] As a further optimization, the matching structure includes a first rectangular matching structure and a second rectangular matching structure. The first rectangular matching structure is made of a copper layer and a nickel layer, with the copper layer located above the nickel layer. The second rectangular matching structure consists of a copper layer-nickel layer-copper layer from top to bottom.

[0029] In a seventh aspect, the present invention provides a probe structure, including a coaxial clamp, the coaxial clamp including a coaxial clamp base, a coaxial clamp top cover and a connector of optional type, the coaxial clamp top cover being located above the coaxial clamp base and connected to each other by screws, the coaxial clamp base having probe mounting slots and positioning pins for mounting the aforementioned enclosed probe structure; the coaxial clamp base having screw holes and cylindrical through holes for connecting the connector of optional type.

[0030] Eighthly, the present invention provides a differential closed probe structure, comprising two aforementioned closed probe structures mirror-symmetrical along a ground line. The differential closed probe structure includes two tip-to-rectangular coaxial line transition structures, two inner conductors of the rectangular coaxial line, two matching structures, three ground lines, and two signal lines. The two signal lines are respectively connected to the matching structures through the tip-to-rectangular coaxial line transition structures and the inner conductors of the rectangular coaxial line; all three ground lines are connected to the outer conductors of the rectangular coaxial line.

[0031] Ninthly, the present invention provides a probe structure, including a differential coaxial clamp, the differential coaxial clamp comprising two coaxial clamps arranged mirror-symmetrically along a centerline, the differential coaxial clamp comprising a differential coaxial clamp base, a differential coaxial clamp top cover, and a connector of optional type, the differential coaxial clamp top cover being located above the differential coaxial clamp base, the differential coaxial clamp base having probe mounting slots and positioning pins for mounting the aforementioned differential enclosed probe structure, and the differential coaxial clamp base having screw holes and cylindrical through holes for connecting the connector of optional type. Beneficial effects

[0032] This invention improves upon traditional millimeter-wave to terahertz frequency probes. Existing probes generally suffer from severe high-frequency radiation crosstalk, abnormal insertion loss, and limitations imposed by additive manufacturing precision, making it difficult to maintain stable impedance matching and signal integrity above 500 GHz. The proposed radiation-suppressing tip structure adds a cantilevered shielding layer to the ground wire, constraining the signal line to quasi-TEM mode for transmission, effectively suppressing high-frequency radiation leakage. Simultaneously, by adjusting the structural parameters of the ground wire length and width, the stress characteristics of the tip are optimized, improving mechanical stability and reliability, and avoiding deformation failure caused by stress concentration during testing. A hollowed-out structure at the root of the G-pin is set near the cantilevered shielding layer, retaining only the nickel layer at this location to offset the mechanical differences caused by the cantilevered shielding layer, ensuring consistency between the G-pin and S-pin under stress, thereby improving the consistency of pin mark depth during chip testing. The radiation-suppressing tip structure employs a gradient design of copper and nickel layers to improve tip visibility, and the functional division between the upper copper layer and the lower nickel layer improves the tip's wear resistance and electrical performance.

[0033] Furthermore, a support structure is introduced between the G-pin and S-pin of the GSG tip structure. The support structure is made of SU8 photoresist to enhance the force balance between the G-pin and S-pin, further improving the mechanical properties and structural stability of the tip, with minimal impact on the electrical performance of the device.

[0034] The two-dimensional probe proposed in this invention simplifies the overall structure and combines a CNC precision-machined metal fixture as an equivalent coaxial external conductor support, thus avoiding the limitations of the multi-layer stacking process in traditional additive manufacturing and breaking through the bottleneck of processing accuracy, enabling the probe to meet the testing requirements within 1.1THz.

[0035] Furthermore, the width of the transition structure from the needle tip to the rectangular coaxial line gradually increases from the needle tip towards the inner conductor of the rectangular coaxial line, thereby achieving impedance matching between the needle tip structure and the rectangular coaxial line.

[0036] Furthermore, the tip structure, the tip-to-rectangular coaxial line transition structure, the rectangular coaxial line, and the rectangular coaxial line-rectangular waveguide conversion structure are all composed of copper and nickel layers, which gives them good consistency in mechanical and electrical properties.

[0037] Furthermore, it also includes a DC bias structure, which realizes a DC lead structure with high isolation, low parasitics, and stable operation, enabling accurate calibration and measurement of active devices in the terahertz band.

[0038] The dual-band two-dimensional probe structure of this invention integrates a high-pass filter, a low-pass filter, and a duplexer within a two-dimensional rectangular coaxial structure, achieving frequency splicing of two high-frequency bands within a single probe. This significantly expands the probe's measurable frequency range and avoids repetitive calibration and error accumulation caused by frequency band switching. The high-pass filter employs a coaxial lumped capacitor structure, resulting in a more compact resonant size and more controllable capacitance. The low-pass filter is based on a T-type SIR + stub loading structure, ensuring good out-of-band rejection and channel isolation. Combining rectangular coaxial-waveguide and rectangular coaxial-circular coaxial conversion structures, the probe is compatible with multiple interfaces and maintains low-loss transmission, achieving integrated, compact, and highly consistent dual-band testing. The differential two-dimensional probe proposed in this invention, by symmetrically arranging two two-dimensional probe units at the center of the ground line, forms a strictly differential symmetrical structure with two signal lines and three ground lines. This effectively suppresses common-mode interference, reduces mode conversion, and significantly improves the consistency and balance of differential-mode excitation, thereby improving the true characterization performance of differential devices in the millimeter-wave to terahertz frequency bands. Furthermore, the differential enclosed probe employs a symmetrical transmission path composed of a closed cavity and a matching structure, achieving higher electromagnetic shielding capabilities while maintaining the differential layout. This reduces radiation leakage and parasitic coupling, enabling the differential signal to maintain lower loss, higher isolation, and better stability in the ultra-high frequency band. Both types of probes significantly improve the measurement accuracy, repeatability, and system adaptability of differential links. Attached Figure Description

[0039] To more clearly illustrate the embodiments of the present invention or the prior art, the accompanying drawings used in the embodiments or the prior art will be briefly described below. It should be noted that the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0040] Figure 1 is an oblique axonometric view of a radiation-suppressing needle tip structure based on additive manufacturing process provided in an embodiment of the present invention;

[0041] Figure 2 is a frontal detail view of a radiation-suppressing needle tip structure based on additive manufacturing process provided in an embodiment of the present invention;

[0042] Figure 3 is a schematic diagram of the reverse side of a radiation-suppressing needle tip structure based on additive manufacturing process provided in an embodiment of the present invention.

[0043] Figure 4 is a schematic diagram of the lower nickel layer structure of a radiation-suppressing needle tip structure based on additive manufacturing process provided in an embodiment of the present invention.

[0044] Figure 5 is a schematic diagram of the upper copper layer structure of a radiation-suppressing needle tip structure based on additive manufacturing process provided in an embodiment of the present invention.

[0045] Figure 6 is an oblique axonometric view of a two-dimensional probe structure based on additive manufacturing process provided in an embodiment of the present invention;

[0046] Figure 7 is a cross-sectional view of a microcoaxial transmission line of a two-dimensional probe structure based on additive manufacturing process provided in an embodiment of the present invention;

[0047] Figure 8 is a schematic diagram of the transition structure from the tip to the rectangular coaxial line of a two-dimensional probe structure based on additive manufacturing process provided in an embodiment of the present invention. a is a schematic diagram of the partial markings of the transition structure from the tip to the rectangular coaxial line of a two-dimensional probe structure based on additive manufacturing process provided in an embodiment of the present invention. b is a magnified view of the partial details of the transition structure from the tip to the rectangular coaxial line.

[0048] Figure 9 is a magnified schematic diagram of the rectangular coaxial line-rectangular waveguide conversion structure and local details in a two-dimensional probe structure based on additive manufacturing process provided by an embodiment of the present invention; a is a schematic diagram of the position of the rectangular coaxial line-rectangular waveguide conversion structure in a two-dimensional probe structure based on additive manufacturing process provided by an embodiment of the present invention, and b is a magnified schematic diagram of local details of the rectangular coaxial line-rectangular waveguide conversion structure.

[0049] Figure 10 is an oblique axonometric view of a two-dimensional probe structure with added DC bias structure based on additive manufacturing process provided in an embodiment of the present invention;

[0050] Figure 11 is a low-pass filter and its detailed magnified view in a two-dimensional probe structure with added DC bias structure based on additive manufacturing process provided by an embodiment of the present invention; a is a schematic diagram of the position of the low-pass filter in a two-dimensional probe structure with added DC bias structure based on additive manufacturing process provided by an embodiment of the present invention, and b is a partial detailed magnified view of the low-pass filter.

[0051] Figure 12 is an oblique axonometric view of a differential two-dimensional probe structure based on additive manufacturing process provided in an embodiment of the present invention;

[0052] Figure 13 is an oblique axonometric view of a dual-band two-dimensional probe structure based on additive manufacturing process provided in an embodiment of the present invention;

[0053] Figure 14 is a magnified view of the duplexer and its details in a dual-band two-dimensional probe structure based on additive manufacturing provided in an embodiment of the present invention; a is a schematic diagram of the position of the duplexer in a dual-band two-dimensional probe structure based on additive manufacturing provided in an embodiment of the present invention, and b is a magnified schematic diagram of the local details of the duplexer.

[0054] Figure 15 is a detailed magnified view of the high-pass filter in a dual-band two-dimensional probe structure based on additive manufacturing technology provided in an embodiment of the present invention; a is a side view of the high-pass filter in a dual-band two-dimensional probe structure based on additive manufacturing technology provided in an embodiment of the present invention, and b is a top view of the high-pass filter;

[0055] Figure 16 is a schematic diagram of the overall structure of a two-dimensional probe structure and waveguide fixture integrated based on additive manufacturing process according to an embodiment of the present invention. a is an oblique axonometric view of a two-dimensional probe structure and waveguide fixture integrated based on additive manufacturing process according to an embodiment of the present invention, and b is a rear view of the two-dimensional probe structure and waveguide fixture integrated.

[0056] Figure 17 is an oblique axonometric cross-sectional view of a closed probe structure based on additive manufacturing process provided in an embodiment of the present invention;

[0057] Figure 18 is a cross-sectional view of a microcoaxial transmission line with a closed probe structure based on additive manufacturing process provided in an embodiment of the present invention.

[0058] Figure 19 is an enlarged view of the matching structure and its details in a closed probe structure based on additive manufacturing process provided in an embodiment of the present invention; a is a schematic diagram of the position of the matching structure in a closed probe structure based on additive manufacturing process provided in an embodiment of the present invention, and b is a partial enlarged view of the matching structure.

[0059] Figure 20 is an oblique axonometric view of a closed probe structure integrated with a coaxial fixture based on additive manufacturing process according to an embodiment of the present invention;

[0060] Figure 21 is an oblique axonometric cross-sectional view of a differential closed probe structure based on additive manufacturing process provided in an embodiment of the present invention;

[0061] Figure 22 is an oblique isometric view of a differential closed probe structure and differential coaxial fixture integrated based on additive manufacturing process provided in an embodiment of the present invention. Embodiments of the present invention

[0062] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that the described embodiments are merely some embodiments of this invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0063] In the description of the embodiments of the present invention, it should be understood that the terms "vertical", "horizontal", "vertical direction", "horizontal direction", "top", "bottom", "left side", "right side", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and should not be regarded as indicating that the indicated element or device is a specific orientation.

[0064] In the description of the embodiments of the present invention, the structural dimensions given are preferred parameters. Referring to the embodiments of the present invention, modifying the dimensional parameters of each component can further obtain the actual required performance.

[0065] Example 1

[0066] This invention provides a radiation-suppressing needle tip structure based on additive manufacturing, comprising a ground wire 6 and a signal line 18. The ground wires 6 are located on both sides of the signal line 18, forming a GSG needle tip structure. The two ground wires 6 are symmetrical about the signal line 18. A support structure 4 passes through the signal line 18, with the two ends of the support structure 4 embedded with the two ground wires 6. The signal line 18 is suspended between the two ground wires 6 through the support structure 4. Both the signal line 18 and the ground wires 6 include a lower nickel layer 1 and an upper copper layer 2 of the GSG needle tip structure. The lower nickel layer 1 of the GSG needle tip structure includes a gradient structure 7 of the lower nickel layer at the tip of the GSG needle tip. The upper copper layer 2 of the GSG needle tip structure includes a hollowed-out structure 3 at the root of the needle, a cantilevered shielding layer 5, and a gradient structure 9 of the upper copper layer at the tip of the GSG needle tip. A gradient structure 8 between the upper copper layer and the lower nickel layer 1 of the GSG needle tip structure is provided. The indentation length d1 of the gradient structure 7 of the nickel layer under the GSG tip and the gradient structure 8 between the upper copper layer and the lower nickel layer is 25-30 μm, and the indentation length d2 of the gradient structure 9 of the upper copper layer under the GSG tip is 40-50 μm. These features are used to increase the visibility of the tip under a vertical microscope during probe detection. The nickel layer 1 under the GSG tip structure is the part where the probe tip contacts the device under test (DUT). Increasing the thickness of the nickel layer 1 under the GSG tip structure can improve the probe's wear resistance and strength. The cantilevered shielding layer 5 can confine the signal line 18 within the electromagnetic field cavity formed by the double-layer ground wire, forcing the signal to be transmitted in quasi-TEM mode and suppressing high-frequency radiation leakage.

[0067] In the GSG tip structure described in this invention, the ground line 6 is a G-pin, and the signal line 18 is an S-pin. The thickness of the nickel layer 1 under the GSG tip structure is 50 μm, and the thickness of the copper layer 2 on the GSG tip structure is 150 μm. The support structure 4 uses SU8 photoresist material with a relative permittivity of 3 and a loss tangent of 0.045, and is used to support the ground line 6, the inner conductor 14 of the rectangular coaxial line, and the transition structure 15 from the tip to the rectangular coaxial line.

[0068] Please refer to Figure 1, an oblique axonometric view of a radiation-suppressing needle tip structure based on additive manufacturing technology provided in an embodiment of the present invention; Figure 2 is a front detail view of a radiation-suppressing needle tip structure based on additive manufacturing technology provided in an embodiment of the present invention; Figure 3 is a reverse structural schematic diagram of a radiation-suppressing needle tip structure based on additive manufacturing technology provided in an embodiment of the present invention, including a support structure 4 and two ground wires 6, with a signal line 18 disposed between the two ground wires 6, the two ground wires 6 being symmetrical about the signal line 18, and the two ground wires 6 and the signal line 18... A GSG tip structure is formed, with signal line 18 suspended between two ground lines 6 via a support structure 4. The support structure 4 passes through signal line 18, and its two ends are embedded in the ground lines 6. Both signal line 18 and the two ground lines 6 include a lower nickel layer 1 and an upper copper layer 2 of the GSG tip structure. A gradient structure 8 between the upper copper layer and the lower nickel layer is provided between the lower nickel layer 1 and the upper copper layer 2 of the GSG tip structure, with a recess length of 25μm, which can increase the visibility of the tip under a vertical microscope during probe detection. The hollowed-out structure 3 at the root of the G-needle is used to offset the mechanical differences caused by the cantilever shielding layer, so that the G-needle and S-needle are consistent under force, thereby improving the consistency of the needle mark depth during chip testing. A cantilever shielding layer 5 is provided above the upper copper layer 2 of the GSG tip structure. Its purpose is to constrain signal line 18 within the electromagnetic field cavity formed by the double ground lines, forcing the signal to be transmitted in quasi-TEM mode and suppressing high-frequency radiation leakage. A support structure 4 is introduced between the G-pin and the S-pin to enhance the force balance between them, further improving the mechanical properties and structural stability of the probe tip. In use, the tip width t of the radiation-suppressing tip structure 10 determines the contact area between the probe tip and the device under test; after optimization, the tip width t is between 10-15 μm.

[0069] Without considering the difficulty of the process, the thickness of the transition structure described in this application can change continuously from the root of the GSG needle tip structure to the tip of the GSG needle tip structure. The curve of the continuous change can be a straight line, a convex curve, or a concave curve.

[0070] The inner conductor protrusion 16 has a size of 100-150 μm, and the rectangular probe 17 has a length of 250-350 μm and a width of 130-180 μm.

[0071] Please refer to Figure 4, which is a schematic diagram of the nickel layer 1 under the GSG tip structure for radiation suppression based on additive manufacturing process, according to an embodiment of the present invention. The structure includes a support structure 4 embedded in the nickel layer 1 under the GSG tip structure and a gradient structure 7 of the nickel layer under the GSG tip tip. The recessed length of the gradient structure 7 of the nickel layer under the GSG tip tip is 25 μm, which increases the visibility of the tip under a vertical microscope.

[0072] Please refer to Figure 5, which is a schematic diagram of the copper layer 2 on the GSG tip structure based on additive manufacturing process for suppressing radiation provided by an embodiment of the present invention. It includes a hollowed-out structure 3 at the root of the G-needle, a cantilevered shielding layer 5, and a copper layer gradient structure 9 on the tip of the GSG tip. The copper layer gradient structure 9 on the tip of the GSG tip has a recessed length of 50 μm, which can increase the visibility of the tip under a microscope.

[0073] Example 2

[0074] The present invention provides a two-dimensional probe comprising a radiation-suppressing tip structure 10 as described in Embodiment 1 above, a tip-to-rectangular coaxial line transition structure 15, a rectangular coaxial line outer conductor 12, a rectangular coaxial line inner conductor 14, a rectangular coaxial line-to-rectangular waveguide conversion structure 13, and a support structure 4. The support structure 4 passes through the rectangular coaxial line inner conductor 14, and the two end support structures 4 are embedded in the rectangular coaxial line outer conductor 12. The rectangular coaxial line inner conductor 14 is suspended within the rectangular coaxial line outer conductor 12 through the support structure 4, forming a rectangular coaxial line structure. The length of the radiation-suppressing tip structure 10 to the tip-to-rectangular coaxial line transition structure 15 determines the matching quality between the radiation-suppressing tip structure 10 and the rectangular coaxial line structure. The optimized length of the tip-to-rectangular coaxial line transition structure 15 is between 150-180 μm. The rectangular coaxial line to rectangular waveguide conversion structure 13 includes an inner conductor protrusion structure 16 and a rectangular probe 17. The rectangular coaxial line to rectangular waveguide conversion structure 13 realizes the conversion from the rectangular coaxial line TEM mode to the rectangular waveguide model. After the parameters are optimized, the probe can achieve good matching with the external connecting waveguide.

[0075] Please refer to Figure 6, which is an isometric view of a two-dimensional probe structure based on additive manufacturing provided in this embodiment of the invention. The structure includes a radiation-suppressing tip structure 10, a tip-to-rectangular coaxial line transition structure 15, an outer conductor 12 of the rectangular coaxial line, an inner conductor 14 of the rectangular coaxial line, a rectangular coaxial line-rectangular waveguide conversion structure 13, and a positioning hole 11 for positioning the probe and fixture. The radiation-suppressing tip structure 10 confines the signal line 18 within the electromagnetic field cavity formed by the double-layer ground wire, forcing the signal to be transmitted in quasi-TEM mode, suppressing high-frequency radiation leakage. It also optimizes the stress structure of the tip, enhancing mechanical stability and reliability, and avoiding deformation and failure caused by stress concentration during high-frequency testing. The outer conductor 12 of the rectangular coaxial line is suspended within the outer conductor 12 by a dielectric support structure 4. The rectangular coaxial line-rectangular waveguide conversion structure 13 is connected to an external rectangular waveguide to achieve a good match between the probe and the external connecting waveguide.

[0076] Please refer to Figure 7, a cross-sectional view of a microcoaxial transmission line of a two-dimensional probe structure based on additive manufacturing technology provided in this embodiment of the invention, wherein the white parts L1, L2-U, and L3 are copper, and the black part L 2-L L2-DS is made of nickel. The mechanical properties of the probe tip can be altered by changing the thickness of the nickel layer. When using this probe, the nickel layer 1 of the GSG probe tip structure repeatedly contacts the chip's DUT.

[0077] Please refer to Figure 8, where a is a partial marked schematic diagram of the transition structure 15 from the tip to the rectangular coaxial line of a two-dimensional probe structure based on additive manufacturing process provided in an embodiment of the present invention, and b is a magnified view of the partial details of the transition structure 15 from the tip to the rectangular coaxial line. The inner conductor of the transition structure 15 from the tip to the rectangular coaxial line is a rectangular structure with a gradually changing width along the axial direction. By changing the gradual length of the inner conductor, a good match is achieved between the radiation-suppressing tip structure 10 and the inner conductor 14 of the rectangular coaxial line.

[0078] Please refer to Figure 9, where a is a schematic diagram of the position of the rectangular coaxial line-rectangular waveguide conversion structure 13 in a two-dimensional probe structure based on additive manufacturing process provided in an embodiment of the present invention, and b is a magnified schematic diagram of a partial detail of the rectangular coaxial line-rectangular waveguide conversion structure 13. The rectangular coaxial line-rectangular waveguide conversion structure 13 includes an inner conductor protrusion structure 16 and a rectangular probe 17. By optimizing the length and width of the inner conductor protrusion structure 16 and the rectangular probe 17, a good match between the two-dimensional probe and the external rectangular waveguide is achieved.

[0079] Please refer to Figure 10, which is an isometric view of a two-dimensional probe structure with an added DC bias structure based on additive manufacturing technology provided in this embodiment of the invention. The structure includes a radiation-suppressing tip structure 10, a tip-to-rectangular coaxial line transition structure 15, an outer conductor 12 of the rectangular coaxial line, an inner conductor 14 of the rectangular coaxial line, a rectangular coaxial line-to-rectangular waveguide conversion structure 13, a support structure 4, and a DC bias structure 21. The DC bias structure 21 includes a low-pass filter 26 and a rectangular coaxial-to-circular coaxial conversion structure 27, both supported by the support structure 4. One end of the low-pass filter 26 is connected to the inner conductor 14 of the rectangular coaxial line, and the other end is connected to the rectangular coaxial-to-circular coaxial conversion structure 27.

[0080] Please refer to Figure 11, where a is a schematic diagram of the position of the low-pass filter 26 in a two-dimensional probe structure with added DC bias structure based on additive manufacturing process provided in an embodiment of the present invention, and b is a magnified schematic diagram of a partial detail of the low-pass filter 26. The low-pass filter 26 is composed of a first-order resonator 28, a second-order resonator 29, a third-order resonator 30, a fourth-order resonator 31, and a fifth-order resonator 32 connected sequentially to the low-pass filter. The first-order resonator 28, the third-order resonator 30, and the fifth-order resonator 32 all use high-resistance lines instead of capacitor structures, and the second-order resonator 29 and the fourth-order resonator 31 both use open-circuit stub lines instead of parallel inductors.

[0081] Example 3

[0082] Please refer to Figure 12, which is an isometric view of a differential two-dimensional probe structure based on additive manufacturing technology provided in this embodiment of the invention. The structure includes two tip-to-rectangular coaxial line transition structures 15, two inner conductors 14 of the rectangular coaxial lines, two rectangular coaxial line-to-rectangular waveguide conversion structures 13, three ground lines 6, and two signal lines 18. The differential two-dimensional probe structure is formed by mirror-symmetrically mirroring the aforementioned two-dimensional probe structure along the ground line 6. The two signal lines 18 are connected to the rectangular coaxial line-to-rectangular waveguide conversion structures 13 via the tip-to-rectangular coaxial line transition structures 15 and the inner conductors 14, respectively. All three ground lines 6 are connected to the outer conductors 12 of the rectangular coaxial lines. The outer conductors 12 have positioning holes 11 for precise positioning with waveguide fixtures. This differential two-dimensional probe structure can meet the testing requirements of differential devices of GSG type 75-110GHz, 110-170GHz, 140-220GHz, 170-260GHz, 220-330GHz, and higher frequency bands.

[0083] Example 4

[0084] Please refer to Figure 13, which is an isometric view of a dual-band two-dimensional probe structure based on additive manufacturing provided in this embodiment of the invention. The structure includes a tip-to-rectangular coaxial line transition structure 15, an inner conductor 14 of the rectangular coaxial line, an outer conductor 12 of the rectangular coaxial line, a rectangular coaxial line-rectangular waveguide conversion structure 13, a duplexer 34, a rectangular coaxial-circular coaxial conversion structure 27, and the aforementioned tip structure 10 for suppressing radiation. The inner conductor 14 of the rectangular coaxial line is suspended within the outer conductor 12 by a support structure 4; a ground wire 6 connects to the outer conductor 12 of the rectangular coaxial line, and a signal line 18 connects to the inner conductor 14 of the rectangular coaxial line through the tip-to-rectangular coaxial line transition structure 15. The rectangular coaxial line-rectangular waveguide conversion structure 13 includes a rectangular probe 17 and an inner conductor protrusion structure 16. The rectangular probe 17 is connected to the duplexer 34 through the inner conductor protrusion structure 16. A waveguide cavity is formed in the outer conductor 12 of the rectangular coaxial line, and the outer side of the rectangular probe 17 is suspended within the waveguide cavity.

[0085] Please refer to Figure 14, where a is a schematic diagram of the position of the duplexer 34 in a dual-band two-dimensional probe structure based on additive manufacturing technology provided in an embodiment of the present invention, and b is a magnified schematic diagram of a partial detail of the duplexer 34. The duplexer 34 includes a high-pass filter 35, a low-pass filter 36 belonging to the duplexer, and a common port 37. The high-pass filter 35 is connected to the rectangular coaxial line-rectangular waveguide conversion structure 13, the low-pass filter 36 belonging to the duplexer is connected to the rectangular coaxial-circular coaxial conversion structure 27, and the common port 37 is connected to the radiation-suppressing tip structure 10 via the inner conductor 14 of the rectangular coaxial line. The high-pass filter 35 is based on a first-order resonant structure and uses a coaxial lumped capacitor structure instead of a low-impedance transmission line. The low-pass filter 36 belonging to the duplexer is based on a T-shaped SIR stub-loaded structure, including a first to a fifth resonator connected in sequence. The first, third, and fifth resonators use high-impedance transmission lines, while the second and fourth resonators use a stub-loaded structure instead of low-impedance transmission lines. This allows for the insertion of multiple transmission zeros to improve the stopband rejection level and enhance the steep drop characteristics of the low-pass filter's response curve. The output ports of the high-pass filter 35, the low-pass filter 36 belonging to the duplexer, and the common port 37 all have an impedance of 50 ohms, achieving good matching with other structures.

[0086] Please refer to Figure 15, where a is a side view of a high-pass filter 35 in a dual-band two-dimensional probe structure based on additive manufacturing provided in an embodiment of the present invention, and b is a top view of the high-pass filter 35. The high-pass filter 35 is based on a coaxial lumped capacitor structure, including a parallel-plate capacitor structure 38, an upper conductor 39, a lower conductor 40, and a rectangular coaxial line outer conductor 12. The parallel-plate capacitor structure 38, the upper conductor 39, and the lower conductor 40 together form the inner conductor, which is set in the rectangular coaxial line outer conductor 12 by a support structure 4. The parallel-plate capacitor structure 38 adopts a metal-dielectric-metal stacked structure, with the upper conductor 39 and the lower conductor 40 connected to its two ends respectively. The length of the overlapping portion of the upper and lower metal layers in the parallel-plate capacitor structure 38 is L1 = 0.07 mm, and the lengths of the upper conductor 12 and the lower conductor 13 are both L2 = 0.07 mm. The upper and lower metal layers in the parallel-plate capacitor structure 38 are located in layers 2-3 and 2-1 respectively, and the dielectric is located in layer 2-2. The upper conductor 39 and the lower conductor 40 are located in layers 2-3 and 2-1, respectively. In addition to the dielectric in the parallel-plate capacitor structure 38, a dielectric is also arranged in the lower layer 2-2 of the upper conductor 39, which generates parasitic capacitance, increasing the realized capacitance value. Similarly, a dielectric can also be arranged in the upper layer 2-2 of the lower conductor 40, further increasing the realized capacitance value. The width of the inner conductor of the parallel-plate capacitor structure 38 is the same as the width of its two sides, the upper conductor 39 and the lower conductor 40, both being W3 = 0.06 mm.

[0087] Example 5

[0088] Please refer to Figure 16, where a is an isometric view of a two-dimensional probe structure integrated with a waveguide fixture based on additive manufacturing technology according to an embodiment of the present invention, and b is a rear view of the two-dimensional probe structure integrated with the waveguide fixture. The waveguide fixture includes a waveguide fixture base 41, a first clamping member 42, a second clamping member 43, and a connector 33 of optional type. The first clamping member 41 and the second clamping member 42 are both located above the waveguide fixture base 41 and are connected to each other to form a waveguide flange structure. The waveguide fixture base 41 has a probe mounting slot and a positioning through hole. A waveguide resonant cavity is formed on the probe mounting slot. The probe mounting slot is used to install the aforementioned two-dimensional probe structure and dual-band two-dimensional probe structure. The depth parameter of the waveguide resonant cavity determines the intrinsic resonance mode of the cavity. By optimizing the design of the depth of the waveguide resonant cavity, it is matched with the waveguide cutoff frequency and resonance conditions of the target operating frequency band, thereby ensuring that the probe output signal can be efficiently excited and achieve complete energy coupling within the required frequency range. The first clamping member 42 has a screw hole 44 and a screw through hole, and the second clamping member 43 has a screw hole 44 and a cylindrical through hole 45 for connection of a connector 33 of optional type, so as to realize the output of DC-110GHz and optional low-frequency signals. The first clamping member 42 and the second clamping member 43 both have waveguide channels 46 inside and extend into waveguide flange structures for the output of 110-170GHz and optional high-frequency signals.

[0089] The probe structure employs a design strategy combining a two-dimensional planar configuration with a hybrid manufacturing process. Specifically, the conductive portion of the two-dimensional probe is integrally formed into a two-dimensional planar structure using additive manufacturing, achieving complex micron-level features. The outer conductor, which serves as shielding and grounding, and the waveguide resonant cavity are precision-machined into an independent waveguide fixture using CNC precision machining. A probe mounting slot is provided at the bottom of the waveguide fixture, and the waveguide resonant cavity is provided on the probe mounting slot. The waveguide resonant cavity extends to the waveguide channel 46 of the waveguide fixture. The waveguide fixture not only provides mechanical support and positioning for the two-dimensional probe body but also acts as an equivalent rectangular coaxial outer conductor, forming a complete transmission system together with the built-in signal body. This decoupled process design avoids the processing accuracy bottlenecks that exist in traditional single additive manufacturing processes when vertically stacked, such as minimum linewidth limitations, insufficient sidewall steepness, and internal stress problems. It fully utilizes the advantages of CNC machining in ultra-high precision and excellent surface finish, thereby successfully extending the upper limit of the probe's reliable operating frequency to 1.1THz while ensuring excellent high-frequency performance. This solution can be used for waveguide testing in the ranges of 75 GHz to 110 GHz, 110 GHz to 170 GHz, 140 GHz to 220 GHz, 170 GHz to 260 GHz, 220 GHz to 325 GHz, 330 GHz to 500 GHz, and 500 GHz to 1100 GHz. Through innovations in both structural reconstruction and process decoupling, it systematically solves the problems of high-frequency radiated crosstalk and terahertz band compatibility.

[0090] Example 6

[0091] Please refer to Figure 17, an isometric cross-sectional view of a closed probe structure based on additive manufacturing provided in this embodiment of the invention. It includes a tip-to-rectangular coaxial line transition structure 15, an inner conductor 14 of the rectangular coaxial line, an outer conductor 12 of the rectangular coaxial line, a matching structure 47, a radiation-suppressing tip structure 10 as described in Embodiment 1, and a positioning hole 11 for positioning the probe and fixture. The inner conductor 14 of the rectangular coaxial line is suspended within the outer conductor 12 of the rectangular coaxial line via a support structure 4. A ground wire 6 connects to the outer conductor 12 of the rectangular coaxial line, and a signal line 8 is sequentially connected to the inner conductor 14 and the matching structure 47 via the tip-to-rectangular coaxial line transition structure 15. The radiation-suppressing tip structure 10 can constrain the signal line 18 within the electromagnetic field cavity formed by the double-layer ground wire, forcing the signal to be transmitted in quasi-TEM mode, suppressing high-frequency radiation leakage. Simultaneously, it can optimize the stress structure of the tip, enhance mechanical stability and reliability, and avoid deformation and failure caused by stress concentration during high-frequency testing. Matching structure 47 is connected to connector 33 of optional type. The port impedance at matching structure 47 is 50 ohms, which is intended to achieve a good match between the enclosed probe structure and the external connector.

[0092] Please refer to Figure 18, a cross-sectional view of a microcoaxial transmission line with a closed probe structure based on additive manufacturing provided in this embodiment of the invention, wherein the white parts L1, L2, L3-U, L4, and L5 are copper, and the black part L 3-L L3-DS is made of nickel. In the enclosed probe structure, the radiation-suppressing tip structure 10, the tip-to-rectangular coaxial line transition structure 15, the inner conductor 14 of the rectangular coaxial line, and the partial matching structure 47 are located in the L3 layer. When using the enclosed probe, the L3 layer of the radiation-suppressing tip structure 10... 3-L The L3-DS section repeatedly contacts the chip's DUT, so the mechanical properties of the tip can be changed by altering the thickness of the nickel layer.

[0093] Please refer to Figure 19, where a is a schematic diagram of the position of the matching structure 47 in a closed probe structure based on additive manufacturing provided in an embodiment of the present invention, and b is a magnified schematic diagram of a partial detail of the matching structure 47. The matching structure 47 includes a first rectangular matching structure 19 and a second rectangular matching structure 20. The first rectangular matching structure 19 is made of a copper layer and a nickel layer, with the copper layer located above the nickel layer; the second rectangular matching structure 20 consists of a copper layer-nickel layer-copper layer from top to bottom. By optimizing the length and width of the first rectangular matching structure 19 and the second rectangular matching structure 20, a good match between the closed probe and the external coaxial connector is achieved.

[0094] Example 7

[0095] Please refer to Figure 20, which is an isometric view of a closed probe structure integrated with a coaxial fixture based on additive manufacturing technology according to an embodiment of the present invention. The coaxial fixture includes a coaxial fixture base 22 and a coaxial fixture top cover 23. The coaxial fixture top cover 23 is located above the coaxial fixture base 22 and is connected to it by screws. The coaxial fixture top cover 23 is provided with pin holes to achieve precise positioning and installation between the coaxial fixture top cover 23 and the coaxial fixture base 22. The coaxial fixture base 22 has probe mounting slots and positioning pins for probe mounting; the coaxial fixture base 22 is provided with screw holes 44 and cylindrical through holes 46 for connection of connectors 33 of optional type to achieve output of DC-110GHz, DC-145GHz, DC-220GHz and wider frequency band signals.

[0096] Example 8

[0097] Please refer to Figure 21, which is an isometric cross-sectional view of a differential closed probe structure based on additive manufacturing technology provided in this embodiment of the invention. The differential closed probe structure is mirror-symmetrically derived from the aforementioned closed probe structure along the ground line, including two tip-to-rectangular coaxial line transition structures 15, two inner conductors 14 of the rectangular coaxial lines, two matching structures 47, three ground lines 6, two signal lines 18, and two positioning holes 11. The two signal lines 18 are connected to the matching structures 47 through the tip-to-rectangular coaxial line transition structures 15 and the inner conductors 14 of the rectangular coaxial lines, respectively; all three ground lines 6 are connected to the outer conductors 12 of the rectangular coaxial lines. This differential closed probe structure can meet the measurement requirements of GSG type differential devices in DC-110GHz, DC-145GHz, DC-220GHz, and wider frequency bands.

[0098] Example 9

[0099] Please refer to Figure 22, which is an isometric view of a differential closed probe structure integrated with a differential coaxial fixture based on additive manufacturing technology, according to an embodiment of the present invention. The differential coaxial fixture includes a differential coaxial fixture base 24 and a differential coaxial fixture top cover 25. The differential coaxial fixture top cover 25 is located above the differential coaxial fixture base 24 and is connected to it by screws. Both the differential coaxial fixture base 24 and the differential coaxial fixture top cover 25 are mirror images of the coaxial fixture base 22 and the coaxial fixture top cover 23 about their center lines. The differential coaxial fixture top cover 25 is provided with pin holes to achieve precise positioning and installation of the differential coaxial fixture base 24 and the differential coaxial fixture top cover 25. The differential coaxial fixture base 24 has differential probe mounting slots and positioning pins for mounting differential enclosed probes. The differential coaxial fixture base 24 is provided with two cylindrical through holes 46 for connecting two optional types of connectors 33 to adapt to the connection requirements of two signals of differential enclosed probes, and realize the output of GSGSG type DC-110GHz, DC-145GHz, DC-220GHz and wider frequency band signals.

[0100] In summary, this invention proposes a radiation-suppressing tip structure, a two-dimensional probe, and a probe structure, including the radiation-suppressing tip structure, the two-dimensional probe, and the probe structure. The radiation-suppressing tip structure constructs a quasi-TEM transmission cavity through a lower nickel-upper copper gradient layer and a cantilevered shielding layer; the two-dimensional probe, combined with the radiation-suppressing tip structure, impedance matching module, and duplexer, achieves broadband matching, and combined with a DC bias module, realizes optional DC bias function; the two-dimensional probe and the enclosed probe, combined with a mirror-symmetric design, expand the measurement function of differential devices. Compared with traditional probe structures, this invention can effectively suppress high-frequency radiation and differential crosstalk, significantly improve the wear resistance, stress balance, and structural stability of the tip, and simultaneously achieve process decoupling and rapid assembly of the probe and fixture. This invention systematically solves the problems of existing high-frequency probes, such as difficulty in broadband matching, serious radiation leakage, insufficient mechanical reliability, and poor engineering adaptability, extending the reliable operating frequency band of the probe to DC-110 GHz and further up to 1.1 THz, providing an engineeringable solution for ultra-wideband high-precision testing of single-ended and differential devices.

[0101] The above is a description of a radiation-suppressing tip structure, a two-dimensional probe, and a probe structure provided by the present invention. For those skilled in the art, based on the ideas of the embodiments of the present invention, there will be changes in the specific implementation methods and application scope.

Claims

1. A radiation-suppressing needlepoint structure, characterized by, It includes a ground wire (6) and a signal wire (18). The ground wire (6) forms a GSG needle tip structure on both sides of the signal wire (18). A support structure (4) is set between the ground wire (6) and the signal wire (18). A cantilever shielding layer (5) is set above the ground wire (6). A G-pin root hollowing structure (3) is opened near the root of the GSG needle tip structure in the cantilever shielding layer (5). Both the ground wire (6) and the signal wire (18) include a nickel layer (1) under the GSG needle tip structure and a copper layer (2) on the GSG needle tip structure. A transition structure is set at the tip of the ground wire (6). The thickness of the transition structure gradually decreases from the root of the GSG needle tip structure to the tip.

2. The radiation suppressing tip structure of claim 1, wherein, Both the ground wire (6) and the signal wire (18) adopt a cantilever structure.

3. The radiation suppressing tip structure of claim 1, wherein, The cantilever shielding layer (5) is located above the copper layer (2) on the GSG tip structure.

4. The radiation suppressing tip structure of claim 1, wherein, The transition structure includes a gradient structure of the nickel layer under the GSG tip (7), a gradient structure between the upper copper layer and the lower nickel layer (8), and a gradient structure of the upper copper layer at the GSG tip (9). The gradient structure of the nickel layer under the GSG tip (7), the gradient structure between the upper copper layer and the lower nickel layer (8), and the gradient structure of the upper copper layer at the GSG tip (9) are all stepped structures.

5. The radiation suppressing tip structure of claim 1, wherein, The thickness of the transition structure changes continuously from the root of the GSG needle structure to the tip of the GSG needle structure.

6. The radiation suppressing tip structure of claim 1, wherein, At the hollowed-out structure (3) at the root of the G needle, the ground wire (6) retains the nickel layer (1) under the GSG needle tip structure.

7. A two-dimensional probe structure, characterized by The system includes a tip-to-rectangular coaxial line transition structure (15), an inner conductor (14) of the rectangular coaxial line, an outer conductor (12) of the rectangular coaxial line, a rectangular coaxial line-rectangular waveguide conversion structure (13), and a tip structure (10) for suppressing radiation as described in any one of claims 1-6. The inner conductor (14) of the rectangular coaxial line is suspended in the outer conductor (12) of the rectangular coaxial line through a support structure (4). The ground wire (6) is connected to the outer conductor (12) of the rectangular coaxial line, and the signal line (18) is connected to the inner conductor (14) of the rectangular coaxial line through the tip-to-rectangular coaxial line transition structure (15). The rectangular coaxial line-rectangular waveguide conversion structure (13) includes a rectangular probe (17) and an inner conductor protrusion structure (16). The rectangular probe (17) is connected to the inner conductor (14) of the rectangular coaxial line through the inner conductor protrusion structure (16). The outer conductor (12) of the rectangular coaxial line has a waveguide cavity, and the outer side of the rectangular probe (17) is suspended in the waveguide cavity.

8. The two-dimensional probe structure of claim 7, wherein, The width of the transition structure (15) from the tip to the rectangular coaxial line gradually increases from the connection point with the signal line (18) toward the inner conductor (14) of the rectangular coaxial line.

9. The two-dimensional probe structure of claim 7, wherein, The inner conductor of the rectangular coaxial line (14), the transition structure from the tip to the rectangular coaxial line (15), the rectangular probe (17), and the protruding structure of the inner conductor (16) are all made of copper and nickel layers, with the copper layer located above the nickel layer.

10. The two-dimensional probe structure of claim 7, wherein, It also includes a DC bias structure (21), which includes a low-pass filter (26) and a rectangular coaxial-to-circular coaxial converter structure (27). The low-pass filter (26) and the rectangular coaxial-to-circular coaxial converter structure (27) are supported in the outer conductor (12) of the rectangular coaxial line by a support structure (4). One end of the low-pass filter (26) is connected to the inner conductor (14) of the rectangular coaxial line, and the other end is connected to the rectangular coaxial-to-circular coaxial converter structure (27).

11. The two-dimensional probe structure of claim 10, wherein, The low-pass filter (26) includes a first-order resonator (28), a second-order resonator (29), a third-order resonator (30), a fourth-order resonator (31), and a fifth-order resonator (32) connected in sequence. The first-order resonator (28), the third-order resonator (30), and the fifth-order resonator (32) of the low-pass filter all use high-resistance lines to replace capacitor structures, and the second-order resonator (29) and the fourth-order resonator (31) of the low-pass filter all use open-circuit stub lines to replace parallel inductors.

12. A differential two-dimensional probe structure, characterized by The differential two-dimensional probe structure includes two tip-to-rectangular coaxial line transition structures (15), two rectangular coaxial line inner conductors (14), two rectangular coaxial line-to-rectangular waveguide conversion structures (13), three ground lines (6), and two signal lines (18). The two signal lines (18) are connected to the rectangular coaxial line-to-rectangular waveguide conversion structures (13) through the tip-to-rectangular coaxial line transition structures (15) and the rectangular coaxial line inner conductors (14), respectively. The three ground lines (6) are all connected to the rectangular coaxial line outer conductors (12).

13. A dual-band two-dimensional geophysical probe structure, characterized by The system includes a tip-to-rectangular coaxial line transition structure (15), an inner conductor (14) of the rectangular coaxial line, an outer conductor (12) of the rectangular coaxial line, a rectangular coaxial line-rectangular waveguide conversion structure (13), a duplexer (34), a rectangular coaxial line-circular coaxial line conversion structure (27), and a tip structure (10) for suppressing radiation as described in any one of claims 1-6; the inner conductor (14) of the rectangular coaxial line is suspended in the outer conductor (12) of the rectangular coaxial line by a support structure (4); a ground wire (6) is connected to the outer conductor (12) of the rectangular coaxial line, and a signal line (18) is connected to the inner conductor (14) of the rectangular coaxial line through the tip-to-rectangular coaxial line transition structure (15); the rectangular coaxial line-rectangular waveguide conversion structure (13) The device includes a rectangular probe (17) and an inner conductor protrusion structure (16). The rectangular probe (17) is connected to the duplexer (34) through the inner conductor protrusion structure (16). A waveguide cavity is opened in the outer conductor (12) of the rectangular coaxial line. The outer side of the rectangular probe (17) is suspended in the waveguide cavity. The duplexer (34) includes a high-pass filter (35), a low-pass filter (36) belonging to the duplexer, and a common port (37). The high-pass filter (35) is connected to the rectangular coaxial line-rectangular waveguide conversion structure (13). The low-pass filter (36) belonging to the duplexer is connected to the rectangular coaxial line-circular coaxial conversion structure (27). The common port (37) is connected to the radiation-suppressing tip structure (10) through the inner conductor (14) of the rectangular coaxial line. The high-pass filter (35) is based on a first-order resonant structure and uses a coaxial lumped capacitor structure to replace the low-impedance transmission line; The low-pass filter (36) belonging to the duplexer is based on a T-shaped SIR stub-loaded structure, including a first resonator to a fifth resonator connected in sequence. The first, third and fifth resonators use high-impedance transmission lines, while the second and fourth resonators use a stub-loaded structure instead of low-impedance transmission lines.

14. The dual-band two-dimensional exploration probe structure according to claim 13, characterized in that, The coaxial lumped capacitor structure includes a parallel plate capacitor structure (38), an upper conductor (39), a lower conductor (40), and a rectangular coaxial line outer conductor (12). The parallel plate capacitor structure (38), the upper conductor (39), and the lower conductor (40) together form the inner conductor, which is set in the rectangular coaxial line outer conductor (12). The parallel plate capacitor structure (38) adopts a metal-dielectric-metal stacked structure. The two ends of the parallel plate capacitor structure (38) are respectively connected to the upper conductor (39) and the lower conductor (40).

15. The dual-band two-dimensional exploration probe structure according to claim 14, characterized in that, The coaxial lumped capacitor structure is based on additive manufacturing and includes a three-layer structure. The parallel plate capacitor structure (38) is located in the second layer, and the rectangular coaxial outer conductor (12) is located in the first to third layers. The second layer is divided into three layers, namely the 2-1 layer, the 2-2 layer and the 2-3 layer. The dielectric of the parallel plate capacitor structure (38) is located in the 2-2 layer, the metal is located in the 2-1 layer and the 2-3 layer, the upper conductor (39) is located in the 2-3 layer, and the lower conductor (40) is located in the 2-1 layer. The area of ​​the parallel plate capacitor structure (38) is proportional to the capacitance value.

16. The dual-band two-dimensional exploration probe structure according to claim 15, characterized in that, In the coaxial lumped capacitor structure, there are multiple periodically arranged support structures (4) between the rectangular coaxial outer conductor (12) and the inner conductor, located in the 2-2 layer, which are used to support the suspended inner conductor. The dielectric in the parallel plate capacitor structure (38) is the same as the dielectric in the support structure (4).

17. A probe structure, characterized in that, The device includes a waveguide clamp, comprising a waveguide clamp base (41), a first clamping member (42), a second clamping member (43), and a connector (33) of optional type. The first clamping member (42) and the second clamping member (43) are both located above the waveguide clamp base (41) and connected to each other. The waveguide clamp base (41) has a probe mounting slot and a positioning through hole. A waveguide resonant cavity is formed on the probe mounting slot. The probe mounting slot is used to install the two-dimensional probe structure as described in any one of claims 7-11 or the dual-band two-dimensional probe structure as described in any one of claims 13-16. The first clamping member (42) has a screw hole (44) and a screw through hole, and the second clamping member (43) has a screw hole (44) and a cylindrical through hole (45) for connection with the connector (33) of optional type. Both the first clamping member (42) and the second clamping member (43) have waveguide channels (46) inside for high-frequency signal output.

18. A closed probe structure, characterized in that, The system includes a needle tip to rectangular coaxial line transition structure (15), a rectangular coaxial line inner conductor (14), a rectangular coaxial line outer conductor (12), a matching structure (47), and a needle tip structure (10) for suppressing radiation as described in any one of claims 1-6; the rectangular coaxial line inner conductor (14) is suspended in the rectangular coaxial line outer conductor (12) by a support structure (4); a ground wire (6) is connected to the rectangular coaxial line outer conductor (12), and a signal line (18) is connected to the rectangular coaxial line inner conductor (14) and the matching structure (47) in sequence through the needle tip to rectangular coaxial line transition structure (15); a positioning hole (11) is provided on the rectangular coaxial line outer conductor (12).

19. The closed probe structure according to claim 18, characterized in that, The matching structure (47) includes a first rectangular matching structure (19) and a second rectangular matching structure (20). The first rectangular matching structure (19) is made of a copper layer and a nickel layer, with the copper layer located above the nickel layer. The second rectangular matching structure (20) consists of a copper layer, a nickel layer, and a copper layer from top to bottom.

20. A probe structure, characterized in that, The coaxial fixture includes a coaxial fixture base (22), a coaxial fixture top cover (23), and a connector (33) of optional type. The coaxial fixture top cover (23) is located above the coaxial fixture base (22) and is connected to each other by screws. The coaxial fixture base (22) has a probe mounting slot and a positioning pin for mounting the closed probe structure as described in claim 18 or 19. The coaxial fixture base (22) is provided with screw holes (44) and cylindrical through holes (45) for connecting the connector (33) of optional type.

21. A differential closed probe structure, characterized in that, The differential closed probe structure includes two tip-to-rectangular coaxial line transition structures (15), two inner conductors (14) of the rectangular coaxial line, two matching structures (47), three ground lines (6), and two signal lines (18). The two signal lines (18) are connected to the matching structures (47) through the tip-to-rectangular coaxial line transition structures (15) and the inner conductors (14) of the rectangular coaxial line, respectively. The three ground lines (6) are all connected to the outer conductors (12) of the rectangular coaxial line.

22. A probe structure, characterized in that, The device includes a differential coaxial clamp, comprising two coaxial clamps arranged symmetrically along a centerline. The differential coaxial clamp includes a differential coaxial clamp base (24), a differential coaxial clamp top cover (25), and a connector (33) of optional type. The differential coaxial clamp top cover (25) is located above the differential coaxial clamp base (24). The differential coaxial clamp base (24) has a probe mounting slot and a positioning pin for mounting the differential closed probe structure as described in claim 21. The differential coaxial clamp base (24) is provided with screw holes (44) and cylindrical through holes (45) for connecting the connector (33) of optional type.

Images