CN115598390A

CN115598390A - Multi-branch coaxial broadband radio frequency probe

Info

Publication number: CN115598390A
Application number: CN202211507219.1A
Authority: CN
Inventors: 刘志广; 蒋文德; 梁铭轩; 郭日耀; 劳杰
Original assignee: Shenzhen Doctor Technology Co ltd
Current assignee: Shenzhen Doctor Technology Co ltd
Priority date: 2022-11-29
Filing date: 2022-11-29
Publication date: 2023-01-13
Anticipated expiration: 2042-11-29
Also published as: CN115598390B

Abstract

The invention relates to a broadband radio-frequency probe with a multi-branch coaxial body, which comprises a shell, a probe, a gasket and the multi-branch coaxial body, wherein a fixed groove is formed in the shell and used for fixing the multi-branch coaxial body, the probe and the gasket, the probe is flaky and provided with a notch used for adjusting impedance matching, one end of the probe is connected with the multi-branch coaxial body, the other end of the probe is exposed for detection, and the gasket is arranged on the probe and used for fixing the probe. The probe is connected with the multi-branch coaxial body through the coplanar waveguide, so that impedance matching (S11 \ S22) of 0-70Ghz is lower than-20 dB, transmission loss (S12 \ S21) is larger than-1 dB, a preset groove is formed in the probe and used for adjusting impedance matching, the gasket is used for fixing the probe and can be matched with the probe to reduce electromagnetic signal transmission loss by adjusting the preset length, the preset width and the preset thickness of the gasket.

Description

Multi-branch coaxial broadband radio frequency probe

Technical Field

The invention relates to the technical field of electromagnetic wave transmission and electronic detection, in particular to a multi-branch coaxial broadband radio frequency probe.

Background

With the development of science and technology, semiconductor technology is changing day by day, and the semiconductor industry is long and will continue to occupy important positions in national comprehensive strength competition and daily life of residents, wherein digital product processor chips and radio frequency device chips are more important products. In the production and manufacturing links of the chip, the wafer on-wafer test and the radio frequency device chip test are carried out through the radio frequency probe, and the radio frequency characteristic parameters of the wafer and the radio frequency device are extracted to detect the quality and debug the performance of the chip, so that the method is an important link for shortening the research and development production period and rapidly analyzing and positioning problems.

The working bandwidth of the rf probe to complete the wafer level test needs to be high precision, low loss, and high repeatability. At present, radio frequency probes in the frequency range of 300Mhz to 300Ghz are mainly designed and produced by the German GGB industrial company and the American Cascade company globally. However, due to lack of options, its high price increases enterprise production costs; the product is in the range of 50 to 67ghz, and the loss is not reduced to the utmost extent.

Disclosure of Invention

In view of this, it is necessary to provide a multi-branch coaxial broadband rf probe, which can effectively reduce transmission loss and save cost through a structure of multiple branches and slots at specific positions.

A broadband radio frequency probe with multiple branches and coaxial bodies comprises a shell, a probe, a gasket and the multiple branches and coaxial bodies, wherein a fixed groove is formed in the shell and used for fixing the multiple branches and coaxial bodies, the probe and the gasket, the probe is flaky and provided with a groove used for adjusting impedance matching, one end of the probe is connected with the multiple branches and coaxial bodies, the other end of the probe is exposed and used for detecting, and the gasket is arranged on the probe and used for fixing the probe.

Furthermore, the probe comprises three probe pieces which are arranged side by side, an S signal line probe piece is arranged in the middle, G signal line probe pieces are arranged on two sides of the S signal line probe piece, the G signal line probe piece is grounded through the shell, the S signal line probe piece is connected with the multi-branch coaxial body and used for conducting electromagnetic signals, a preset distance is arranged between the S signal line probe piece and the G signal line probe pieces on two sides, the edges of the G signal line probe piece are respectively L19, L16, L18, L17, L9, L11, L12, L13, L14, L15, W16, W17 and W9, the L19 is 0.85mm, the L16 is 3.38mm, the L18 is 0.33mm, the L17 is 1.86mm, the L9 is 1.78mm, the L11 is 0.4mm, the L12 is 0.11mm +/-0.05 mm, the L13 is 0.38mm, the L14 is 0.25mm, the L9 is 0.05mm, the L11 is 0.15mm, the L12 mm, the W9 is 0.02mm, and the W9 is 0.02mm; the edges of the S signal wire probe sheet are respectively L16, W10 and W13, wherein the L16 is 3.38mm, the W10 is 0.14mm, and the W13 is 0.02mm; the thickness h1 of the G signal wire probe piece and the S signal wire probe piece is 0.16mm.

Furthermore, each G signal line probe piece is provided with a G signal needle point part, each S signal line probe piece is provided with an S signal needle point part, and the upper surface and the lower surface of the G signal needle point part and the upper surface and the lower surface of the S signal needle point part are on the same horizontal plane respectively.

Further, two of the G signal tip portions have a frontmost G signal tip face, the S signal tip portion has a frontmost S signal tip face, and a distance W14 between a center of the G signal tip face and a center of the S signal wire tip face is 0.15mm.

Furthermore, a cutting groove is formed in the tails of the two G signal wire probe sheets, a sinking groove is formed in the tail of each G signal wire probe sheet facing the end face of the S signal wire probe sheet, notches are formed in the end faces of the two G signal wire probe sheets facing the S signal wire probe sheet, the notches are close to the tail of the S signal wire probe sheet, an inclined portion is arranged at the edge of the end face of the S signal wire probe sheet, which is far away from the probe needles of the G signal wire probe sheets, the probes of the two G signal wire probe sheets are identical in shape and size and the grooves formed in the probe sheets, and are arranged on two sides of the S signal wire probe sheet in a bilateral symmetry manner.

Furthermore, the notch edges are L14 and W17, the width of the W17 is 0.12 +/-0.02 mm, the width of the L14 is 0.25 +/-0.05 mm, the cutting groove is acute, the edges are L11 and L19, the width of the L11 is 0.4mm, the width of the L19 is 0.85mm, the width of the sinking groove edges is L12 and W9, the width of the L12 is 0.11 +/-0.05 mm, the width of the W9 is 0.045 +/-0.01 mm, and the distance between the notch and the sinking groove is 0.38mm.

Furthermore, the gasket is square and has two blocks, and the two blocks are respectively clamped and arranged on the two sides of the upper surface and the lower surface of the probe, the gasket has a preset width, a preset length and a preset thickness, and the gasket and the notch jointly adjust the impedance matching of the probe.

Further, the gasket is made of polytetrafluoroethylene, the dielectric constant of the gasket is 2.1, the gasket edges are W11, L10 and h2, the W11 is 1.80mm, the L10 is 1.25mm, and the h2 is 1.1mm.

Further, the multi-branch coaxial body is provided with four sections in a combination mode of adopting a tapered gradual change structure, the multi-branch coaxial body is provided with an input port, the input port is an input port with the diameter of 1.85mm, the multi-branch coaxial body is divided into a first shaft body, a second shaft body, a third shaft body and a fourth shaft body, the lengths of the first shaft body, the second shaft body, the third shaft body and the fourth shaft body are h6, h7, h8 and h9 respectively, the h6 is 4mm, the h7 is 4.4mm, the h8 is 4mm, and the h9 is 2.18mm.

Furthermore, the joint of the third shaft body and the fourth shaft body is fixed by a polytetrafluoroethylene sleeve, so that the multi-branch coaxial shaft body is always kept at a preset position.

According to the broadband radio-frequency probe with the multi-branch coaxial bodies, the probe, the gasket and the multi-branch coaxial bodies are arranged in the shaping groove of the shell, the probe is connected with the multi-branch coaxial bodies through the coplanar waveguide, so that the impedance matching (S11 \ S22) at 0-70Ghz can be lower than-20 dB, the transmission loss (S12 \ S21) is larger than-1 dB, the probe is provided with the preset groove for adjusting the impedance matching, the gasket is used for fixing the probe and can be matched with the probe to reduce the transmission loss of electromagnetic signals by adjusting the preset length, the preset width and the preset thickness of the gasket.

Drawings

The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort. In the drawings:

FIG. 1 is a schematic structural diagram of a multi-branched coaxial broadband RF probe according to the present invention.

Fig. 2 is a schematic structural view of the present invention with the outer shell removed.

Fig. 3 is a schematic view of the present invention with the housing and gasket removed.

FIG. 4 is a schematic diagram of the dimensioning of the multi-branched coaxial broadband RF probe of the present invention.

FIG. 5 is a schematic diagram of another angle dimension marking of the multi-branched coaxial broadband RF probe of the present invention.

FIG. 6 is a schematic diagram of the top-view dimension labeling of the multi-branched coaxial broadband RF probe of the present invention.

FIG. 7 is a schematic diagram of the probe size marking of the present invention.

FIG. 8 is a graph of the effect of the size of the multi-limbed coaxial body L12 of the present invention on high frequency.

FIG. 9 is a graph of the effect of the size of the multi-limbed coaxial body R3 of the present invention on high frequency.

FIG. 10 is a graph of the effect of the size of the multi-limbed coaxial body R5 of the present invention on high frequency.

FIG. 11 shows the variation of the parameters of the S-signal wire probe sheet with frequency according to the present invention.

Wherein, the first and the second end of the pipe are connected with each other,

100 multi-branch coaxial broadband radio frequency probes;

20 a housing;

30, probe: 31S signal wire probe sheet, 32G signal wire probe sheet, 33 cutting groove, 34 notch, 35 inclined part and 36 sinking groove;

40 a gasket;

50 multi-branch coaxial bodies: 51 input port, 52 sleeve, 53 first shaft, 54 second shaft, 55 third shaft, 56 fourth shaft.

Detailed Description

It is to be understood that the terminology, the specific structural and functional details disclosed herein are for the purpose of describing particular embodiments only, and are not intended to be limiting, since the present invention may be embodied in many alternate forms and should not be construed as limited to only the embodiments set forth herein.

The present invention will be described in detail below with reference to specific embodiments and the accompanying drawings.

Referring to fig. 1, fig. 2 and fig. 3, a multi-arm coaxial broadband radio frequency probe 100 according to an embodiment of the present invention is shown, and includes a housing 20, a probe 30, a pad 40 and a multi-arm coaxial body 50, where a fixed groove is disposed in the housing 20 and is used to fix the multi-arm coaxial body 50, the probe 30 and the pad 40, the probe 30 is in a sheet shape and is provided with a slot for adjusting impedance matching, one end of the probe 30 is connected to the multi-arm coaxial body 50, and the other end of the probe is exposed for detection, and the pad 40 is disposed on the probe 30 and is used to fix the probe 30. The housing 20 is preferably a brass housing, the probe 30 is preferably a metal probe, the operating frequency range of the probe 30 is 0-70Ghz, the impedance match is < -20dB, the spacer 40 is not only used for fixing the probe 30, but also can reduce the transmission loss of electromagnetic signals by adjusting the predetermined length, the predetermined width and the predetermined thickness of the spacer 40 to match with the probe 30.

Preferably, referring to fig. 3, 6 and 7, the probe 30 includes three probe 30 pieces arranged side by side, an S signal line probe piece 31 is arranged in the middle, G signal line probe pieces 32 are arranged at two sides of the S signal line probe piece 31, the G signal line probe pieces 32 are grounded through the housing 20, the S signal line probe piece 31 is connected with the multi-branched coaxial body 50 for conducting electromagnetic signals, a predetermined distance is provided between the S signal line probe piece 31 and the G signal line probe pieces 32 at two sides, the sides of the G signal line probe sheet 32 are respectively L19, L16, L18, L17, L9, L11, L12, L13, L14, L15, W16, W17 and W9, the L19 is 0.85mm, the L16 is 3.38mm, the L18 is 0.33mm, the L17 is 1.86mm, the L9 is 1.78mm, the L11 is 0.4mm, the L12 is 0.11mm +/-0.05 mm, the L13 is 0.38mm, the L14 is 0.25mm +/-0.05 mm, the L15 is 0.75mm, the W16 is 0.405mm, the W17 is 0.12mm +/-0.02 mm, and the W9 is 0.045mm +/-0.01 mm; the edges of the S signal wire probe sheet 31 are respectively L16, W10 and W13, the L16 is 3.38mm, the W10 is 0.14mm, and the W13 is 0.02mm; the thickness h1 of the G signal wire probe piece 32 and the S signal wire probe piece 31 is 0.16mm. The distance between the S signal wire probe sheet 31 and the G signal wire probe sheets 32 on both sides is 0.085mm, impedance matching can be significantly affected by adjusting the distance between the S signal wire metal probe sheet 31 and the two G signal wire metal probe sheets 32 and the size of the probe sheets, and the impedance matching effect of the width of the S signal wire metal probe sheet 31 affecting the frequency of 50Ghz or more is significant.

Preferably, each of the G signal line probe tiles 32 has a G signal tip portion, and the S signal line probe tile 31 has an S signal tip portion, and upper and lower surfaces of the G signal tip portion and the S signal tip portion are in the same horizontal plane. And the G signal needle point part and the S signal needle point part are both used for contact testing Pad.

Preferably, two of the G signal tip portions have a frontmost G signal tip face, the S signal tip portion has a frontmost S signal tip face, and a distance W14 between a center of the G signal tip face and a center of the S signal wire tip face is 0.15mm. The contact distance between the S-signal wire probe chip 31 and the transmission line to be tested affects impedance matching of high frequency.

Preferably, the two G signal wire probe sheets 32 have a cutting groove 33 at the tail portion, the two G signal wire probe sheets 32 have a sinking groove 36 at the end surface facing the S signal wire probe sheet 31 at the tail portion, the two G signal wire probe sheets 32 have a notch 34 at the end surface facing the S signal wire probe sheet 31, the notch 34 is close to the tail portion of the S signal wire probe sheet 31, the G signal wire probe 30 is provided with an inclined portion 35 at the edge of the end surface far away from the S signal wire probe sheet 31, the two G signal wire probe sheets 32 have the same shape and size and the same grooves, and are symmetrically arranged at the two sides of the S signal wire probe sheet 31. The sunken grooves 36 on two sides are positioned at the tail end of the G signal wire probe piece 32, so that the bandwidth and the transmission loss can be adjusted, the cutting groove 33 prevents the S signal wire probe piece 31 from being grounded, and the notches 34 are connected with the gasket 40 to jointly adjust the impedance matching of the metal sheet probe 30.

Preferably, the edges of the notch 34 are L14 and W17, the width of the W17 is 0.12 ± 0.02mm, the width of the L14 is 0.25 ± 0.05mm, the notch 33 is acute-angled, the edges are L11 and L19, the width of the L11 is 0.4mm, the width of the L19 is 0.85mm, the edges of the sink groove 36 are L12 and W9, the width of the L12 is 0.11 ± 0.05mm, the width of the W9 is 0.045 ± 0.01mm, and the distance from the notch 34 to the sink groove is 360.38mm. The predetermined size of the slot is effective to reduce transmission loss.

Preferably, referring to fig. 2, the spacer 40 is a square spacer and has two pieces, which are respectively clamped on the upper and lower sides of the probe 30, the spacer 40 has a predetermined width, a predetermined length and a predetermined thickness, and the spacer 40 and the notch 34 cooperate to adjust the impedance matching of the probe 30. By adjusting the thickness of the spacer 40, the transmission loss can be adjusted, and by adjusting the length and width of the fixed spacer 40, the impedance matching can be adjusted.

Preferably, referring to fig. 7, the gasket 40 is made of teflon, the dielectric constant of the gasket 40 is 2.1, the edges of the gasket 40 are W11, L10 and h2, the W11 is 1.80mm, the L10 is 1.25mm and the h2 is 1.1mm. The polytetrafluoroethylene gasket 40 can resist high temperature, the transmission loss of the probe 30 is related to the dielectric constant of the material of the gasket 40, the transmission loss can be effectively reduced by adopting the dielectric constant of 2.1, and the transmission loss can be more effectively reduced by combining the preset length, the preset width and the preset thickness of the polytetrafluoroethylene.

Preferably, referring to fig. 4 and 5, the multi-branch coaxial body 50 has a combination manner in which four sections adopt a tapered gradual structure, the multi-branch coaxial body 50 has an input port 51, the input port 51 is an input port 51 with a diameter of 1.85mm, the multi-branch coaxial body 50 is divided into a first shaft body 53, a second shaft body 54, a third shaft body 55 and a fourth shaft body 56, the lengths of the first shaft body 53, the second shaft body 54, the third shaft body 55 and the fourth shaft body 56 are h6, h7, h8 and h9, respectively, the length of h6 is 4mm, the length of h7 is 4.4mm, the length of h8 is 4mm, and the length of h9 is 2.18mm. The radiuses of the multi-branch coaxial bodies 50 are different, the bandwidth of the high frequency band is adjusted by adjusting the length of each section of the coaxial body and the radius of the shaft core, the multi-branch coaxial bodies 50 are obliquely arranged relative to the probe 30, and the fourth shaft body 56 and the S signal line probe sheet 31 form an included angle of 150 degrees and are welded and fixed.

Preferably, referring to fig. 2 and 3, the connection between the third shaft body 55 and the fourth shaft body 56 is fixed by a teflon sleeve 52, so that the multi-branched coaxial shaft body 50 is always kept at a predetermined position. The teflon sleeve 52 is effective to adjust the impedance matching.

In the broadband radio frequency probe 100 with the multi-branch coaxial body, the probe 30, the spacer 40 and the multi-branch coaxial body 50 are arranged in a fixed groove of the housing 20, the two tails of the G signal line probe pieces 32 are respectively provided with the cutting grooves 33 with the preset size, which not only can improve impedance matching but also can prevent the S signal line probe piece 31 from being grounded, the sinking grooves 36 arranged on the two G signal line probe pieces 32 can adjust the bandwidth and transmission loss thereof, the spacer 40 can be used for fixing the probe 30, and can also adjust impedance matching by adjusting the preset length and the preset width of the spacer 40 to be matched with the notches 34 in the middle section of the G signal line probe piece 32, reduce electromagnetic signal transmission loss by adjusting the preset thickness of the spacer 40, and the impedance matching can be significantly influenced by the preset distance between the S signal line probe piece 31 and the G signal line probe pieces 32 on both sides; the multi-branch coaxial body 50 has a combination mode that four sections adopt a gradually-reducing type gradually-changing structure, the bandwidth of a high frequency range of the multi-branch coaxial body is adjusted by adjusting the length of each section of the coaxial body and the radius of a shaft core, the S signal line probe sheet 31 is fixedly connected with the multi-branch coaxial body 50 through the coplanar waveguide, so that the impedance matching (S11 \ S22) of 0-70Ghz is lower than-20 dB, the transmission loss (S12 \ S21) is larger than-1 dB, the multi-branch coaxial body has good transmission function and detection function, the loss in the transmission process is effectively reduced, the structure is simple, and the investment cost is effectively reduced.

The impedance matching and transmission loss of the multi-branch coaxial broadband radio frequency probe 100 are further described by combining experiments:

the specific dimensions of the multi-branched coaxial broadband RF probe are shown in the following table.

Unit: millimeter (mm)

Referring to fig. 4, 5, 6, 7, 8, 9, 10, and 11, it is shown that the curves of the dimensions of the multi-branched coaxial broadband rf probe 100, the probe 30, and the spacer 40 versus the S parameter measured by the HFSS simulation software show that the frequency band of the working range of the broadband millimeter wave rf probe 30 (S11 \ S22 < -10 dB) is 0Ghz-69.91Ghz, and the average insertion loss in the pass band (| S21| \\ | S12 |) is about 0.6 dB. As can be seen from the figure, the final performance graph of fig. 11 is obtained by integrating the effects of the main parameters such as L12 decrease, R3 increase, and R5 increase.

From the test results, the broadband radio frequency probe 30 provided by the invention widens the test frequency range of the chip to 0-69.91 Ghz, and has excellent performance.

The foregoing is a more detailed description of the invention in connection with specific alternative embodiments, and the practice of the invention should not be construed as limited to those descriptions. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims

1. The broadband radio-frequency probe is characterized by comprising a shell, a probe, a gasket and a multi-branch coaxial body, wherein a fixed groove is formed in the shell and used for fixing the multi-branch coaxial body, the probe and the gasket, the probe is sheet-shaped, a groove used for adjusting impedance matching is formed in the probe, one end of the probe is connected with the multi-branch coaxial body, the other end of the probe is exposed and used for detecting, and the gasket is arranged on the probe and used for fixing the probe.

2. The broadband radio-frequency probe with multiple coaxial sections according to claim 1, wherein the probe comprises three probe sheets arranged side by side, an S signal line probe sheet is arranged in the middle, G signal line probe sheets are arranged on two sides of the S signal line probe sheet, the G signal line probe sheet is grounded through the housing, the S signal line probe sheet is connected with the multiple coaxial sections for conducting electromagnetic signals, a predetermined distance is arranged between the S signal line probe sheet and the G signal line probe sheets on two sides, the G signal line probe sheets have edges of L19, L16, L18, L17, L9, L11, L12, L13, L14, L15, W16, W17, W9, the L19 is 0.85mm, the L16 is 3.38mm, the L18 is 0.33mm, the L17 is 1.86mm, the L9 is 1.78mm, the L11 is 0.4mm, the L12 is 0.11mm ± 0.05mm, the L13 mm, the L18 is 0.33mm, the L17 is 1.86mm, the L405 mm is 1.78mm, the L11 is 0.13 mm, the L13 mm, the L0.27 mm, the W0.02 mm, the 0.05mm, the W9 mm is 0.02mm, the 0.75 mm; the edges of the S signal wire probe sheet are respectively L16, W10 and W13, wherein the L16 is 3.38mm, the W10 is 0.14mm, and the W13 is 0.02mm; the thickness h1 of the G signal wire probe piece and the S signal wire probe piece is 0.16mm.

3. The multi-branched coaxial broadband radio frequency probe according to claim 2, wherein each of the G signal line probe pieces has a G signal tip portion, and the S signal line probe piece has an S signal tip portion, and the G signal tip portion and the S signal tip portion are on the same horizontal plane.

4. The multi-limbed coaxial body broadband radio frequency probe according to claim 3, wherein two of said G-signal tip portions have a forwardmost G-signal tip face, said S-signal tip portion has a forwardmost S-signal tip face, and the center of said G-signal tip face is at a distance W14 of 0.15mm from the center of said S-signal wire tip face.

5. The multi-section coaxial broadband radio frequency probe according to claim 4, wherein two of the tails of the G signal line probe pieces have a notch, two of the tails of the G signal line probe pieces have a sunken notch facing the end surface of the S signal line probe piece, two of the G signal line probe pieces have a notch corresponding to the end surface facing the S signal line probe piece, the notch is close to the tail of the S signal line probe piece, the edge of the G signal line probe piece away from the end surface of the S signal line probe piece has an inclined portion, and the two G signal line probe pieces have the same shape, size and the respective notches, and are symmetrically disposed on two sides of the S signal line probe piece.

6. The broadband radio frequency probe with multiple stubs and coaxial bodies of claim 5, wherein the notch edge is L14, W17, the W17 is 0.12 ± 0.02mm, the L14 is 0.25 ± 0.05mm, the notch is acute-angled, the edge is L11, L19, the L11 is 0.4mm, the L19 is 0.85mm, the sink notch edge is L12, W9, the L12 is 0.11 ± 0.05mm, the W9 is 0.045 ± 0.01mm, and the notch is 0.38mm from the sink notch.

7. The multi-branch coaxial broadband radio-frequency probe according to claim 6, wherein the spacer is a square spacer and has two pieces, the two pieces are respectively clamped on two sides of the upper surface and the lower surface of the probe, the spacer has a predetermined width, a predetermined length and a predetermined thickness, and the spacer and the notch jointly adjust impedance matching of the probe.

8. The multi-legged coaxial broadband rf probe according to claim 7, wherein the spacer is ptfe, the dielectric constant of the spacer is 2.1, the spacer edges are W11, L10, h2, the W11 is 1.80mm, the L10 is 1.25mm, and the h2 is 1.1mm.

9. The broadband radio frequency probe with multiple branches and spindles of claim 8, wherein the multiple branches and spindles have a combination of four sections with a tapered and gradually changed structure, the multiple branches and spindles have an input port, the input port is an input port with a diameter of 1.85mm, the multiple branches and spindles are divided into a first spindle, a second spindle, a third spindle and a fourth spindle, the first spindle, the second spindle, the third spindle and the fourth spindle have lengths h6, h7, h8 and h9, respectively, the length of h6 is 4mm, the length of h7 is 4.4mm, the length of h8 is 4mm, and the length of h9 is 2.18mm.

10. The multi-segmented coaxial body broadband rf probe of claim 9, wherein the junction of said third body and said fourth body is secured by a teflon sleeve, which keeps said multi-segmented coaxial body in a predetermined position at all times.