Punching and grounding coplanar waveguide structure suitable for synchrotron radiation X-ray measurement

Abstract

The utility model discloses a punching and grounding coplanar waveguide structure suitable for synchrotron radiation X-ray measurement. The punching and grounding coplanar waveguide structure comprises a dielectric substrate, a first metal surface layer and a second metal surface layer, wherein the first metal surface layer and the second metal surface layer are respectively positioned on the upper surface and the lower surface of the dielectric substrate; a coplanar waveguide signal conductor is arranged in the first metal surface layer; a non-metal through hole is formed in the middle of the dielectric substrate, and a plurality of metalized through holes for connecting the first metal surface layer and the second metal surface layer are formed in the periphery of the dielectric substrate; one end of the coplanar waveguide signal conductor is in direct short-circuit connection with the first metal surface layer to form a microwave magnetic field stagnation point, and the other end is separated from the first metal surface layer through a gap. According to the utility model, through the design of the coplanar waveguide signal conductor of which the single end is directly short-circuited and grounded and the non-metal through hole close to a microwave magnetic field stationary point, excellent microwave magnetic field stability is realized in a broadband range, the microwave magnetic field intensity is obviously enhanced, and the sensitivity and the resolution of synchrotron radiation X-ray measurement are improved.

Description

Technical Field

[0001] This utility model relates to the field of synchrotron radiation X-ray measurement technology, specifically to a perforated grounded coplanar waveguide structure suitable for synchrotron radiation X-ray measurement. Background Technology

[0002] Ferromagnetic resonance (FMR) technology is an important tool for studying the dynamic properties of magnetic materials, and grounded coplanar waveguides (GCPWs), as a highly efficient microwave transmission structure, can efficiently transmit microwave fields, provide a uniform magnetic field distribution, and support high-frequency and high-resolution measurements. Their planar structure and miniaturized design make them an important tool in FMR technology, particularly suitable for research in thin film materials, nanomaterials, and spintronics.

[0003] Recent advancements in synchrotron X-ray-based ferromagnetic resonance (citation to CN116520221A, "A Time- and Space-Resolved GHz Spin Precession Detection Method and System") enable element-resolved and phase-resolved ultrafast magnetic dynamics measurements by synchronizing X-ray pulse characteristics with microwave detection phase. However, while existing perforated waveguide structures can effectively excite sample precession at low frequencies, they cannot provide sufficient microwave magnetic fields within the synchrotron X-ray detection region at higher frequencies, thus limiting the phase detection accuracy and frequency range of magnetic material spin precession. Therefore, it is necessary to develop a novel perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurements to achieve efficient spin precession excitation over a wide frequency range. Summary of the Invention

[0004] Based on the technical problems existing in the background technology, this utility model proposes a perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement, aiming to solve the problem that the current perforated waveguide cannot achieve GHz spin precession measurement at higher frequencies.

[0005] This utility model is achieved through the following technical solution:

[0006] A perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurements includes:

[0007] A dielectric substrate, a first metal surface layer located on the upper surface of the dielectric substrate, and a second metal surface layer located on the lower surface of the dielectric substrate; a coplanar waveguide signal conductor is disposed in the first metal surface layer; wherein:

[0008] A non-metallic via is provided in the middle of the dielectric substrate for placing the sample to be tested; the non-metallic via is located on the centerline of the coplanar waveguide signal conductor, and the non-metallic via divides one end of the coplanar waveguide signal conductor into a ring-like shape; the non-metallic via penetrates the first metal surface layer, the dielectric substrate and the second metal surface layer.

[0009] A plurality of metallized vias are provided around the dielectric substrate for connecting the first metal surface layer and the second metal surface layer.

[0010] One end of the coplanar waveguide signal conductor is directly connected to the first metal surface layer to form a microwave stagnation point. A non-metallic via is located near the microwave stagnation point to ensure a stable microwave magnetic field strength at different microwave frequencies. The other end of the coplanar waveguide signal conductor is separated from the first metal surface layer by a gap.

[0011] As a preferred technical solution, the coplanar waveguide signal conductor includes a short-circuit grounding end and a signal input end. The short-circuit grounding end is the end closest to the non-metallic via, which is directly short-circuited to the first metal surface layer to form a microwave magnetic field stagnation point to enhance the microwave magnetic field strength. The width of the coplanar waveguide signal conductor changes at the non-metallic via, always maintaining a constant width in the direction perpendicular to the coplanar waveguide signal transmission. The signal input end is separated from the first metal surface layer by a gap. The gap includes a first gap and a second gap symmetrically distributed on both sides of the coplanar waveguide signal conductor. The first gap includes a first straight end and a first semi-circular end, and the second gap includes a second straight end and a second semi-circular end. The first and second semi-circular ends are symmetrically distributed on both sides of the non-metallic via, and the centers of the first and second semi-circular ends are concentric with the center of the non-metallic via. The shape design of the semi-circular segments in the gaps ensures that the gap width remains constant in the direction perpendicular to the coplanar waveguide signal transmission.

[0012] As a preferred technical solution, metallized vias are symmetrically distributed on both sides of the centerline of the dielectric substrate to prevent electromagnetic waves from generating a parallel plate pattern between the upper and lower surfaces of the dielectric substrate.

[0013] As a preferred technical solution, the spacing between any two adjacent metallized vias is the same, i.e., the metallized vias are arranged at equal intervals. More preferably, the spacing between the metallized vias is greater than the diameter of the metallized vias.

[0014] As a preferred technical solution, the diameter of the non-metallic via is not less than the thickness of the dielectric substrate, ensuring that the incident synchrotron X-rays can be tilted to a certain extent. More preferably, the non-metallic via is a tapered hole to further enhance the microwave magnetic field strength in the central region of the hole and reduce microwave loss.

[0015] This utility model has the following beneficial effects:

[0016] This application proposes a perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement. This perforated grounded coplanar waveguide structure not only has excellent microwave magnetic field stability over a wide frequency range, but also significantly enhances the microwave magnetic field strength, thereby improving the sensitivity and resolution of synchrotron X-ray measurement. This can expand the application scope of synchrotron X-ray measurement technology in the study of the dynamic properties of magnetic materials. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement, provided as an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the structure of the first metal surface layer.

[0019] Figure 3 A simulation of a perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement is provided for embodiments of this utility model. 11 Parameter diagram.

[0020] Figure 4 This invention provides a simulated microwave magnetic field distribution diagram of the centerline surface of a perforated grounded coplanar waveguide structure substrate suitable for synchrotron radiation X-ray measurement at different frequencies, as provided in an embodiment of the present invention.

[0021] Figure 5 The top and bottom images on the left are simulation diagrams of the microwave magnetic field intensity at positions a and b in the first metal surface layer, respectively. The top and bottom images on the right are ferromagnetic resonance signals obtained by testing at the corresponding positions of the perforated grounded coplanar waveguide sample provided in this embodiment of the invention.

[0022] Reference numerals: 1-Dielectric substrate, 2-Coplanar waveguide signal conductor, 3-First metal surface layer, 4-Second metal surface layer, 5-Non-metallic via, 6-Metalized via, 7-First gap, 701-First straight end, 702-First semi-circular end, 8-Second gap, 801-Second straight end, 802-Second semi-circular end. Detailed Implementation

[0023] The present invention will be further described below with reference to embodiments, so that those skilled in the art can better understand and implement the present invention, but the embodiments are not intended to limit the present invention.

[0024] In the description of this utility model, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations of this utility model. The terms "first" and "second" mentioned in this utility model do not represent a specific quantity or order, but are merely used for distinguishing names. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0025] refer to Figure 1 , Figure 2 This utility model provides a perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement, comprising a dielectric substrate 1, a first metal surface layer 3 located on the upper surface of the dielectric substrate, and a second metal surface layer 4 located on the lower surface of the dielectric substrate; a coplanar waveguide signal conductor 2 is arranged in the first metal surface layer 1; a non-metallic through-hole 5 is formed at the middle position of the dielectric substrate 1; the non-metallic through-hole 5 is located on the centerline of the coplanar waveguide signal conductor 2, and the non-metallic through-hole 5 divides one end of the coplanar waveguide signal conductor into a near-circular shape, while the other end of the coplanar waveguide signal conductor is rectangular; the non-metallic through-hole 5 penetrates the first metal surface layer 3, the dielectric substrate 1, and the second metal surface layer 4; a plurality of metallized vias 6 are formed around the periphery of the dielectric substrate 1 for connecting the first metal surface layer 3 and the second metal surface layer 4.

[0026] In this embodiment, the coplanar waveguide signal conductor 2 includes a short-circuit grounding end and a signal input end; the short-circuit grounding end is the end close to the non-metallic via, which is directly short-circuited to the first metal surface layer to form a microwave magnetic field stagnation point to enhance the microwave magnetic field strength; the signal input end is separated from the first metal surface layer by a gap; the gap includes a first gap 7 and a second gap 8 symmetrically distributed on both sides of the coplanar waveguide signal conductor; the first gap 7 includes a first straight end 701 and a first semi-circular end 702, and the second gap 8 includes a second straight end 802 and a second semi-circular end 802. The first semi-circular end 702 and the second semi-circular end 802 are symmetrically distributed on both sides of the non-metallic via 5, and the center of the first semi-circular end and the center of the second semi-circular end are concentric with the center of the non-metallic via.

[0027] In this embodiment, the dielectric substrate 1 is made of non-metallic material with a flame retardant rating of FR-4, a thickness h of 0.71 mm, a length L of 27 mm, a width W of 10 mm, and a metal layer thickness t of 35 μm on the upper and lower surfaces.

[0028] In this embodiment, the length l of the coplanar waveguide signal conductor 2 is... s It is 18mm long and the width is w. sThe signal input end is 1mm thick, and the two sides are separated from the first metal surface layer by gaps. The gaps include a first gap 7 and a second gap 8 symmetrically distributed on both sides of the coplanar waveguide signal conductor. The width g of the first gap and the second gap is 0.3mm, and the gap depth is 35μm, which is the thickness of the first metal surface layer on the upper surface of the dielectric substrate 1. This ensures that the characteristic impedance of the grounded coplanar waveguide is always maintained at the standard impedance of 50Ω. The other end is directly connected to the first metal surface layer, so that the microwave magnetic field forms a stagnation point at the connection, ensuring the strength and broadband stability of the microwave magnetic field.

[0029] In this embodiment, the first metal surface layer 3 and the second metal surface layer 4 are connected by 52 symmetrically distributed metallized vias 6 uniformly arranged on both sides of the coplanar waveguide signal conductor 2, preventing electromagnetic waves from generating a parallel plate pattern between the upper and lower surfaces of the dielectric substrate. The radius r of each metallized via 6 is 0.3 mm, the spacing d between two adjacent metallized vias 6 along the long side of the substrate is 1 mm, the distance d1 between the center of the metallized via 6 at the signal input end of the coplanar waveguide signal conductor 2 and the edge of the coplanar waveguide signal conductor 2 is 0.9 mm, and the distance d2 between the center of the metallized via 6 on the short-circuit grounding end side and the centerline of the first metal surface layer is 1.4 mm.

[0030] In this embodiment, the radius R of the non-metallic via 5 penetrating the dielectric substrate 1, the coplanar waveguide signal conductor 2, and the first metal surface layer 3 is 0.65 mm, slightly smaller than the thickness of the dielectric substrate, enabling approximately 60° tilted synchrotron X-ray incidence. The center of the non-metallic via 5 is located on the centerline of the coplanar waveguide signal conductor, at a distance l from the signal input end of the coplanar waveguide signal conductor 2. r It is 17.5mm, close to the microwave magnetic field stagnation point.

[0031] like Figure 3 The figure shown is a simulation S11 parameter diagram of a perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement provided by an embodiment of this utility model. S11 decreases monotonically in the frequency range from DC to 10 GHz, and S11 is -1.13 dB at 10 GHz, which has good impedance matching and meets the requirements for low loss of microwave waveguides in synchrotron X-ray ferromagnetic resonance technology.

[0032] like Figure 4 The figure shows a simulated microwave magnetic field distribution at different frequencies in a cross-section of a perforated grounded coplanar waveguide structure substrate suitable for synchrotron X-ray measurement, provided by an embodiment of this utility model. Simulation results show that a microwave magnetic field stagnation point exists at the connection between the coplanar waveguide signal conductor and the first metal surface layer, maintaining a certain microwave magnetic field strength at different microwave frequencies. However, the microwave magnetic field distribution far from the connection point is significantly affected by the microwave frequency. The non-metallic via is located near the microwave magnetic field stagnation point, effectively ensuring the broadband stability of the microwave magnetic field at the center of the non-metallic via.

[0033] like Figure 5 As shown, this is an embodiment of the present invention providing a perforated grounded coplanar waveguide structure suitable for synchrotron radiation X-ray measurement, with the upper surface of the dielectric substrate. Figure 2 Simulation diagrams of microwave magnetic field strength at positions a and b are shown, along with ferromagnetic resonance signals obtained from tests at corresponding positions on the perforated grounded coplanar waveguide sample provided in this embodiment of the invention. Simulation results show that in the wide bandwidth region from DC to 10 GHz, the microwave magnetic field at point a, the center of the non-metallic via, always maintains effective strength. The presence of a microwave magnetic field stagnation point causes the microwave magnetic field to monotonically decrease from 0.230 Oe at DC to 0.195 Oe at 10 GHz, with a maximum microwave magnetic field attenuation of approximately 15.2% due to the microwave frequency. However, at point b, which is far from the microwave magnetic field stagnation point, the microwave magnetic field changes non-monotonicly with the microwave frequency, reaching a maximum attenuation of approximately 98.3% at 5.2 GHz. The results obtained in ferromagnetic resonance experiments conducted using an iron-nickel alloy sample at the corresponding positions on the perforated grounded coplanar waveguide sample provided in this embodiment of the invention verify the simulation results. Ferromagnetic resonance signals from the sample are consistently obtained when tested at point a, while at point b, the sample signal is significantly affected by frequency, almost disappearing at 5 GHz.

[0034] Figure 4 , 5 The results fully demonstrate the broadband stability of the perforated grounded coplanar waveguide structure provided for synchrotron X-ray measurement in this embodiment of the invention, which meets the requirements for broadband stability of microwave magnetic fields in synchrotron X-ray ferromagnetic resonance technology.

[0035] As a further optimization in this embodiment, the shape of the non-metallic through hole is adjusted. By using a tapered hole to reduce the aperture at the coplanar waveguide signal conductor, the loss of the microwave waveguide structure of this utility model can be effectively reduced and the microwave magnetic field strength can be significantly improved.

[0036] Compared with existing technologies, this invention, through the design of a coplanar waveguide signal conductor with direct short-circuit grounding at one end and a non-metallic through-hole near the microwave magnetic field stagnation point, not only has excellent microwave magnetic field stability over a wide frequency range, but also significantly enhances the microwave magnetic field strength, improves the sensitivity and resolution of synchrotron radiation X-ray measurement, and can expand the application scope of synchrotron radiation X-ray measurement technology in the study of the dynamic properties of magnetic materials.

[0037] The above-described specific implementations may be adjusted in various ways by those skilled in the art without departing from the principles and purpose of this utility model. These adjustments should also be considered as the scope of protection of this utility model. The scope of protection of this utility model is defined by the claims and is not limited to the above-described specific implementations. All implementation schemes within its scope are subject to the constraints of this utility model.

Claims

1. A perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement, characterized in that, include: A dielectric substrate, a first metal surface layer located on the upper surface of the dielectric substrate, and a second metal surface layer located on the lower surface of the dielectric substrate; a coplanar waveguide signal conductor is disposed in the first metal surface layer; wherein: A non-metallic via is provided at the middle position of the dielectric substrate, and the non-metallic via is located on the centerline of the coplanar waveguide signal conductor; the non-metallic via penetrates the first metal surface layer, the dielectric substrate, and the second metal surface layer. The dielectric substrate has a plurality of metallized vias around its periphery for connecting the first metal surface layer and the second metal surface layer. One end of the coplanar waveguide signal conductor is directly connected to the first metal surface layer, and the other end of the coplanar waveguide signal conductor is separated from the first metal surface layer by a gap.

2. The perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement according to claim 1, characterized in that, The coplanar waveguide signal conductor includes a short-circuit grounding terminal and a signal input terminal; the short-circuit grounding terminal is the end closest to the non-metallic via, which is directly connected to the first metal surface layer to form a microwave stagnation point; the signal input terminal is separated from the first metal surface layer by a gap; the gap includes a first gap and a second gap symmetrically distributed on both sides of the coplanar waveguide signal conductor; the first gap includes a first straight end and a first semi-circular end, and the second gap includes a second straight end and a second semi-circular end, the first semi-circular end and the second semi-circular end are symmetrically distributed on both sides of the non-metallic via, and the center of the first semi-circular end and the center of the second semi-circular end are concentric with the center of the non-metallic via.

3. The perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement according to claim 1, characterized in that, The metallized vias are symmetrically distributed on both sides of the centerline of the dielectric substrate.

4. The perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement according to any one of claims 1 to 3, characterized in that, The spacing between any two adjacent metallized vias is the same.

5. The perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement according to claim 4, characterized in that, The spacing between the metallized vias is greater than the diameter of the metallized vias.

6. The perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement according to any one of claims 1 to 3, characterized in that, The diameter of the non-metallic through-hole is not less than the thickness of the dielectric substrate.

7. The perforated grounded coplanar waveguide structure suitable for synchrotron X-ray measurement according to claim 6, characterized in that, The non-metallic through hole is a tapered hole.

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