Resonant circuit, and method for manufacturing an inductor and a capacitor.

Abstract

To provide a technique for easily balancing weight of a resonance circuit.SOLUTION: A resonance circuit includes an inductor formed along a surface of a first cylindrical shape having a central axis, and a capacitor formed along a surface of a second cylindrical shape having a central axis, where the inductor and the capacitor are electrically connected to each other to form a closed loop.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a resonance circuit, and a method for manufacturing an inductor and a capacitor.

Background Art

[0002] An NMR (nuclear magnetic resonance) apparatus irradiates a sample placed in a strong magnetic field with RF (radio waves) to cause nuclear magnetic resonance, and detects an NMR signal using a coil for detection, for example, to analyze the molecular structure of the sample. NMR measurement is a measurement that can analyze materials that can only be obtained and synthesized in trace amounts in a non-destructive manner, and thus is used in the field of new material search. As a method for improving the detection sensitivity of the NMR signal of this trace sample, a method of increasing the magnetization of the nuclear spin system by increasing the static magnetic field applied to the sample (increasing the measurement frequency) has been pursued for many years. However, in recent years, situations such as the enlargement of facilities and the increase in costs for increasing the static magnetic field have occurred.

[0003] Also, when the sample is trace and the signal intensity is weak, in order to obtain an NMR spectrum with sufficient accuracy, etc., it is necessary to perform integration many times, so a long measurement time is required. As a result, there may be cases where the machine time is insufficient, or when the sample is a biochemical sample, etc., the sample cannot withstand the long measurement, etc., making analysis difficult.

[0004] On the other hand, as a method used to sharpen the NMR spectrum in a solid NMR apparatus, a method called MAS (Magic Angle Spinning) is known, in which a sample tube with a sample inserted therein is tilted at an angle called the magic angle (about 54.7°) with respect to the direction of the strong magnetic field, and the sample tube is rotated and measured in that state.

[0005] In recent years, a technique called MACS (Magic Angle Coil Spinning) has attracted attention for its aim to improve the detection sensitivity of signals when measuring trace amounts of samples in MAS-NMR. This technique involves inserting the sample inside the inductor of a resonant circuit consisting of an inductor and a capacitor connected in series, and then placing the entire resonant circuit containing the sample into a sample tube for MAS-NMR measurement (see Non-Patent Documents 1 and 2). The RF magnetic field generated inside the inductor is amplified by the resonance of this resonant circuit, thereby increasing the detection sensitivity of the NMR signal. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] D. Sakellariou, G. Le Goff & J. -F, Jacquinot. (2007) High-resolution, high-sensitivity NMR of nanolitre anisotropic samples by coil spinning, Nature, 447, 694-697. [Non-Patent Document 2] V. Badilita, B. Fassbender, K. Kratt, A. Wong, C. Bonhomme,D. Sakellariou, JG Korvink, U. Wallrabe (2012) Microfabricated Inserts for Magic Angle Coil Spinning (MACS) Wireless NMR Spectroscopy, PLOS ONE, 7, e42848. [Overview of the project] [Problems that the invention aims to solve]

[0007] In MAS-NMR, the sample tube is rotated at high speed (for example, around 3000 rotations per second) to sharpen the spectrum. Therefore, it is necessary to fill the sample tube with the sample in a way that prevents it from losing balance during rotation. This is also true for MACS-NMR, as mentioned above. If the weight balance of the sample tube in the direction of rotation or along its long axis is disrupted, the rotation axis of the sample tube will wobble during rotation. The sample tube is housed in an expensive NMR probe, and if the rotation axis of the sample tube wobbles during rotation, the sample tube may come into contact with the NMR probe, potentially damaging it.

[0008] In the techniques described in Non-Patent Documents 1 and 2, the resonant circuit provided inside the sample tube consists of a commercially available capacitor connected to a hand-wound copper wire coil. As a result, the weight balance of the sample tube cannot be achieved, making it impossible to rotate the sample tube at a sufficiently high speed.

[0009] The present invention was made in such circumstances, and one exemplary objective of a certain embodiment is to provide a technique for facilitating weight balancing of a resonant circuit. [Means for solving the problem]

[0010] To solve the above problems, a resonant circuit according to one aspect of the present disclosure comprises an inductor formed along the surface of a first cylindrical shape having a central axis, and a capacitor formed along the surface of a second cylindrical shape having a central axis. The inductor and the capacitor are electrically connected to each other to form a closed loop.

[0011] Another aspect of the present disclosure is a method for manufacturing an inductor and a capacitor. This manufacturing method includes a first forming step of forming a first conductive layer along the outer surface of a cylindrical tube on the outer surface of a cylindrical tube; a second forming step of forming an insulating layer on the surface of the first conductive layer formed in the first forming step; and a third forming step of forming a second conductive layer on the surface of the insulating layer formed in the second forming step.

[0012] Furthermore, any combination of the above components, as well as any conversion of the expressions of this disclosure between methods, apparatus, systems, etc., are also valid as aspects of this disclosure. [Effects of the Invention]

[0013] This disclosure provides a technique for facilitating weight balancing of resonant circuits. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1(a) is a schematic diagram of an NMR apparatus according to one embodiment of the present disclosure. Figure 1(b) is a diagram showing the configuration inside the probe according to the same embodiment. [Figure 2] This is a schematic diagram of the detection unit according to the same embodiment. [Figure 3] This figure shows the vane portion of the sample tube according to the same embodiment. [Figure 4] This is a circuit diagram of the internal resonant circuit according to the same embodiment. [Figure 5] Figure 5(a) is an external view of the internal resonant circuit according to the same embodiment. Figure 5(b) is a diagram showing the first layer of the internal resonant circuit according to the same embodiment. Figure 5(c) is a diagram showing the second layer of the internal resonant circuit according to the same embodiment. Figure 5(d) is a diagram showing the third layer of the internal resonant circuit according to the same embodiment. [Figure 6] Figure 6(a) shows a portion of the cross-section of the A-A' region shown in Figure 5(a). Figure 6(b) shows a portion of the cross-section of the B-B' region shown in Figure 5(a). [Figure 7] Figure 7(a) shows a first modified example of the internal resonant circuit. Figure 7(b) shows a second modified example of the internal resonant circuit. [Figure 8] Figure 8(a) is an external view of the internal resonant circuit according to the second modified example. Figure 8(b) is a diagram showing the first layer of the internal resonant circuit according to the second modified example. Figure 8(c) is a diagram showing the second layer of the internal resonant circuit according to the second modified example. Figure 8(d) is a diagram showing the third layer of the internal resonant circuit according to the second modified example. [Figure 9]FIG. 9(a) is a diagram showing the pattern of the first layer of the internal resonance circuit according to an embodiment of the present disclosure. FIG. 9(b) is a diagram showing the pattern of the second layer of the internal resonance circuit according to the embodiment. FIG. 9(c) is a diagram showing the pattern of the third layer of the internal resonance circuit according to the embodiment. [Figure 10] FIG. 10(a) is a diagram showing a modified example of the pattern of the first layer of the internal resonance circuit. FIG. 10(b) is a diagram showing a modified example of the pattern of the second layer of the internal resonance circuit. FIG. 10(c) is a diagram showing a modified example of the pattern of the third layer of the internal resonance circuit. [Figure 11] FIG. 11(a) is a diagram for explaining the process of filling ink having a predetermined pattern in the gravure plate. FIG. 11(b) is a diagram for explaining the process of causing the ink filled in the gravure plate to be received by the transfer roller. FIG. 11(c) is a diagram for explaining the process of transferring the ink onto the surface of the cylindrical tube. [Figure 12] It is a diagram for explaining a modified example of the method of attaching ink to the cylindrical tube. [Figure 13] FIGS. 13(a) to 13(f) are diagrams showing a method of forming the first conductive layer of the internal resonance circuit by photolithography. [Figure 14] FIGS. 14(a) to 14(f) are diagrams showing a method of forming the insulating layer of the internal resonance circuit by photolithography. [Figure 15] FIGS. 15(a) to 15(c) are diagrams showing a modified example of the method of forming the insulating layer (using a permanent resist as the resist). [Figure 16] FIGS. 16(a) to 16(c) are diagrams showing a modified example (lift-off method) of the method of forming the insulating layer. [Figure 17] FIGS, 17(a) to 17(f) are diagrams showing a method of forming the second conductive layer of the internal resonance circuit by photolithography. [Figure 18] In the resonance characteristic evaluation of Evaluation Example 3, FIG. 18(a) shows the electrical circuit of the system used for the evaluation, FIG. 18(b) is a photograph showing the appearance of the system used for the evaluation, and FIG. 18(c) shows the evaluation results. [Figure 19]In the simulation of the vibrational magnetic field strength in Evaluation Example 4, Figure 19(a) shows the model used in the calculation, Figures 19(b) and 19(c) show the simulation results, and Figure 19(d) shows the frequency dependence of the magnetic field strength at the center of the internal resonant circuit in the simulation. [Modes for carrying out the invention]

[0015] [Embodiment] Figures 1(a) and 1(b) are schematic diagrams of an NMR apparatus according to one embodiment of the present disclosure. As shown in Figure 1(a), the NMR apparatus comprises a magnet 1 that generates a static magnetic field in the Z-axis direction (vertical direction) and a probe 2 that houses a detection unit 20 on which a sample is placed. The detection unit 20 is equipped with a coil that generates radio waves (hereinafter also referred to as "RF coil") placed around the sample. In NMR measurement, NMR occurs in the sample when the RF coil irradiates the sample with radio waves in the static magnetic field generated from the magnet 1. The signal generated based on that NMR is detected.

[0016] The internal configuration of probe 2 will be explained in more detail with reference to Figure 1(b). As shown in Figure 1(b), a housing 102 is located inside probe 2, and inside the housing 102 are the detection unit 20, turbine stator 104, gas bearing stator 106, and the like.

[0017] During measurement, the detection unit 20 is positioned to face a direction (the R-axis direction in Figure 1(b)) that is tilted by an angle called the magic angle from the direction of the static magnetic field (the Z-axis direction in Figure 1(b)). The detection unit 20 includes an RF coil 200, a sample 210, and a sample tube 220, among other things. A detailed configuration of the detection unit 20 will be described later with reference to Figure 2.

[0018] The housing 102 is supplied with compressed air from two separate systems. Specifically, compressed air is supplied to the gas bearing stator 106 that supports the sample tube 220 through the flow path 110. Compressed air is also supplied to the turbine stator 104 through the flow path 108, and this compressed air is used as a driving source to rotate the sample tube 220.

[0019] Figure 2 is a schematic diagram of the detection unit 20 according to this embodiment. As shown in Figure 2, the detection unit 20 according to this embodiment includes a sample tube 220, a cylindrical tube 24 disposed inside the sample tube 220, an internal resonant circuit 26 formed along the surface of the cylindrical tube 24, and an RF coil 28 that is non-contacting and facing the outer circumference of the sample tube 220 when the sample tube 220 is attached to the probe 2.

[0020] The sample tube 220 comprises a vane section 222, a housing section 225, and a bottom section 227. The housing section 225 houses the cylindrical tube 24, the internal resonant circuit 26, and the sample 210. The vane section 222 and the bottom section 227 are provided at one end and the other end of the housing section 225, respectively, and function as a lid for the housing section 225.

[0021] The sample tube 220 is inserted at an angle tilted by a magic angle from the Z-axis direction and rotates around its central axis (R-axis). Specifically, the sample tube 220 rotates when compressed air is received by the blade portion 222 provided at the end of the sample tube 220 from the turbine stator 104 located inside the probe 2.

[0022] This rotation will be explained with reference to Figures 2 and 3. Figure 3 shows the vane portion 222 of the sample tube 220 as viewed from the W direction shown in Figure 2. As indicated by the arrow in Figure 2, the sample tube 220 rotates as shown in Figure 3 when the vane portion 222, which is the end of the sample tube 220, receives compressed air (wind). Since the wind hits the end of the sample tube 220 and not the center of the sample tube 220, not only the weight balance around the rotation axis shown in Figure 2, but also the weight balance in the longitudinal direction of the sample tube 220 shown in Figure 2 is important. For example, if the sample 210 is placed near the end of the sample tube 220, or if the sample 210 moves inside the sample tube 220, the sample tube 220 cannot be rotated. Generally, the sample is placed in the center of the sample tube 220 to achieve balance in the longitudinal direction.

[0023] The internal resonant circuit 26 comprises circuit elements (specifically, an inductor 260 and a capacitor 262 shown in Figure 2) fabricated by laminating a conductive layer and an insulating layer on the outer surface of a cylindrical tube 24. Figure 4 is a circuit diagram of an internal resonant circuit according to one embodiment of the present disclosure, in which the inductor 260 (L1) and the capacitor 262 (C1) are electrically connected in parallel to form a closed circuit.

[0024] During NMR measurement, the RF coil 28 generates radio waves based on a signal transmitted from an external device (not shown). At this time, the internal resonant circuit 26 resonates, amplifying the radio waves. The amplified radio waves irradiate the sample 210 placed inside the cylindrical tube 24, causing the sample 210 to undergo NMR. The RF coil 28 detects the signal based on this NMR, and the external device analyzes the sample 210 based on the detected signal. In this embodiment, since the radio waves are amplified by the internal resonant circuit 26, the signal based on NMR becomes stronger compared to when the internal resonant circuit 26 is not present, and the detection sensitivity is increased.

[0025] The internal resonant circuit 26 according to this embodiment is provided inside the sample tube 220 and on the surface of the cylindrical tube 24. The cylindrical tube 24 is a hollow tube having a cylindrical outer surface (hereinafter referred to as the "outer surface") and a cylindrical inner surface. The sample 210 to be measured by NMR measurement is placed inside the internal resonant circuit 26. The internal resonant circuit 26 is fixed to the sample tube 220, and when the sample tube 220 rotates, the internal resonant circuit 26 rotates together with the sample tube 220 and the sample 210 around its central axis.

[0026] Furthermore, in this embodiment, the overall center of gravity of the sample tube 220 and the internal resonant circuit 26 (and cylindrical tube 24) inserted into the sample tube 220 is the same as the center of gravity of the sample tube 220 without the internal resonant circuit 26 (and cylindrical tube 24) inserted. As a result, the sample tube 220 with the internal resonant circuit 26 (and cylindrical tube 24) inserted can rotate stably around the rotation axis R at the rotation speed required for MAS-NMR (for example, around 3 to 20 kHz), with the central axis R of the sample tube 220 tilted by a magic angle from the direction of the static magnetic field (Z axis direction). Note that by adjusting the probe 2, the sample tube can be rotated stably even at a rotation speed of around 500 Hz. The upper and lower limits of the rotation speed of the sample tube 220 that can be rotated stably depend on the size of the probe 2 and sample tube 220 of the MAS-NMR apparatus, but by using the internal resonant circuit 26 of this disclosure, vibration of the sample tube 220 can be suppressed, and the sample tube 220 can be rotated over a wide range from the lower limit to the upper limit of the rotation speed.

[0027] The configuration of the internal resonant circuit 26 according to this embodiment will be described in detail with reference to Figures 5(a) to 5(d). Figure 5(a) is a diagram showing the cylinder of the internal resonant circuit 26 according to this embodiment unfolded over its entire circumference, and Figures 5(b) to 5(d) show the first to third layers of the internal resonant circuit 26 according to this embodiment, respectively. The internal resonant circuit 26 according to this embodiment is constructed by stacking a first conductive layer (first layer), an insulating layer (second layer), and a second conductive layer (third layer) patterned in an arbitrary shape, and is configured as the resonant circuit shown in Figure 4. Therefore, each layer structure will be explained separately. Figures 5(b) to 5(d) are shown as diagrams showing the first to third layers of the internal resonant circuit 26 formed on the cylindrical tube 24 unfolded over its entire circumference, similar to Figure 5(a).

[0028] As shown in Figure 5(a), the internal resonant circuit 26 comprises various components that constitute the resonant circuit, and more specifically, a wiring section 310 that constitutes an inductor, an upper electrode 330 that constitutes a capacitor, and an insulating layer 320. The wiring section 310, whose outline is shown by a dashed line, is formed on the lower side of the insulating layer 320. Here, the length of the inductor is p. The area S of the capacitor formed by the upper electrode 330 can be approximated by the size of the upper electrode 330 when the cylindrical tube 24 is unfolded, and in the example shown in Figure 5(a), S = n × m. The configuration of each layer will be described in detail below with reference to Figures 5(b) to (d).

[0029] As shown in Figure 5(b), the first layer of the internal resonant circuit according to this embodiment comprises a wiring section 310, a connecting wire 312 connected to the wiring section 310, and a rectangular lower electrode 314 connected to the wiring section 310. The wiring section 310 constitutes the inductor L1 shown in Figure 4. The lower electrode 314 constitutes one electrode of the capacitor C1 shown in Figure 4. The connecting wire 312 is formed to encircle the cylindrical tube 24.

[0030] As shown in Figure 5(c), the second layer of the internal resonant circuit according to this embodiment includes an insulating layer 320. The insulating layer 320 is a layer containing an insulator, and may contain, for example, various dielectric materials. The insulating layer 320 constitutes the interlayer insulating film of the capacitor C1 shown in Figure 4. The insulating layer 320 is formed to cover the wiring portion 310 and the lower electrode 314 of the first layer.

[0031] As shown in Figure 5(d), the third layer of the internal resonant circuit according to this embodiment has a rectangular upper electrode 330 and a connecting wire 332 when viewed in a rectangular cross-section. The upper electrode 330 constitutes the other electrode of the capacitor C1 shown in Figure 4, and the lower electrode 314 of the first layer, the insulating layer 320 of the second layer, and the upper electrode 330 of the third layer constitute the capacitor C1. The upper electrode 330 is connected to the connecting wire 312 of the first layer at a contact 333 via the connecting wire 332. As a result, the capacitor C1 is connected to the inductor L1 which is formed by the wiring section 310 of the first layer.

[0032] Here, we will explain why the first and third layers are connected via the connecting wire 312. Basically, it is sufficient for the first and third layers to be in contact, but when the first and third layers are formed on the cylindrical tube 24 by, for example, the printing method described later, if the alignment is not correct and the first and third layers are misaligned in the circumferential direction, it may not be possible to connect the first and third layers. In this embodiment, since each layer is formed by the printing method, a pattern with a large alignment margin in the circumferential direction (i.e., the printing direction) makes circumferential alignment easier. However, as mentioned above, there are cases where the first and third layers cannot be connected as they are. Therefore, in this embodiment, the connecting wire 312 of the first layer is provided to go around the cylindrical tube 24 in the circumferential direction, so that the contact point between the first and third layers may be at any position on the cylindrical tube. This allows the contact point 333 to be formed even if the connecting wire 332 of the third layer is misaligned in the circumferential direction, and thus the first and third layers can be connected. This makes it possible to connect the first and third layers while widening the alignment margin. Therefore, the shape of the connecting lines 312 and 332 can be any shape as long as they can connect the first and third layers.

[0033] In this way, by stacking the first to third layers, the internal resonant circuit 26 according to this embodiment can have a structure in which a capacitor C1 and an inductor L1 are connected in series. In this embodiment, since the capacitor and inductor are formed on the surface of the cylindrical tube 24, weight imbalance in the direction of the long axis of the internal resonant circuit 26 and the rotation axis of the sample tube is suppressed. Therefore, when the sample tube 220 rotates due to wind during MACS-NMR measurement, the sample tube 220 is less likely to lose its balance.

[0034] Figure 6(a) shows a portion of the cross-section of the A-A' region shown in Figure 5(a). The internal resonant circuit 26 is formed by laminating a first conductive layer, an insulating layer 320, and a second conductive layer on the surface of a cylindrical tube 24. The sample 210 is placed inside the cylindrical tube 24.

[0035] As shown in Figure 6(a), the first layer includes the lower electrode 314 of the capacitor, the wiring sections 310a to 310f that constitute the inductor, and the connecting wire 312. The second layer, an insulating layer 320, is formed to cover the surfaces of the lower electrode 314 and the wiring section 310 of the capacitor. In this embodiment, the insulating layer 320 insulates the inductor from the outside while forming the interlayer insulating film of the capacitor. The third layer, a second conductive layer, includes the upper electrode 330 of the capacitor and the connecting wire 332 that connects the third layer and the first layer. In addition, an insulating layer that serves as a protective layer may be formed on the third layer for the purpose of protecting the capacitor and contacts.

[0036] Figure 6(b) is a cross-section of the B-B' region shown in Figure 5(a). The lower electrode 314, insulating layer 320, and upper electrode 330 shown in Figure 6(b) constitute the capacitor of the internal resonant circuit. In this embodiment, the electrodes constituting one capacitor are formed around the entire circumference of the cylindrical tube, but multiple electrodes formed along the circumference may constitute the capacitor. For example, the upper electrode of the capacitor constituting the second conductive layer may be composed of multiple electrodes that are separated from each other. By forming different electrodes individually, the capacitance of the capacitor included in the internal resonant circuit can be adjusted by scraping each electrode, etc. This makes it possible to adjust the impedance of the internal resonant circuit more easily.

[0037] When performing NMR measurements, the sample is placed inside the cylindrical tube 24. In particular, when the amount of sample is small, it is preferable to place the sample 210 inside the region of the internal resonant circuit 26 where the wiring sections 310a to 310f constituting the inductor are formed. In this embodiment, this allows the radio waves amplified by the internal resonant circuit to be efficiently supplied to the sample 210, thereby improving the accuracy of the NMR measurement.

[0038] Here, we will explain some variations of the internal resonant circuit using Figures 7(a) and 7(b). Figure 7(a) shows the first variation of the internal resonant circuit, and Figure 7(b) shows the second variation of the internal resonant circuit.

[0039] As shown in Figure 7(a), the internal resonant circuit according to the first modified example has one inductor L2 connected in parallel with two capacitors C2 and C3. Also, as shown in Figure 7(b), the internal resonant circuit according to the second modified example has one inductor L3 connected in parallel with multiple capacitors C11, C12, C21 and C22. Although Figure 7(b) shows four capacitors connected in parallel with inductor L3, the number of capacitors connected in parallel with inductor L3 may be three or fewer, or five or more.

[0040] Referring to Figures 8(a) to 8(d), the configuration of the internal resonant circuit in the second modified example will be explained in more detail when there are four capacitors connected in parallel with the inductor L3. Figure 8(a) shows the external appearance of the internal resonant circuit in the second modified example, and Figures 8(b) to 8(d) show the first to third layers of the internal resonant circuit in the second modified example.

[0041] The internal resonant circuit according to the second modified example, as shown in Figure 8(a), comprises various components that constitute the internal resonant circuit, such as the wiring section 410 that constitutes the inductor, the upper electrodes 430, 432, 434, and 436 that constitute the capacitor, and the insulating layers 420, 422, and 424. The wiring section 410, whose outline is shown by a dashed line, is formed on the lower side of the insulating layer 422. All capacitors formed on the surface of the cylindrical tube 24 are connected in parallel, and their total area S may be approximated to the sum of the areas of the upper electrodes 430, 432, 434, and 436 when the cylindrical tube 24 is unfolded. The configuration of each layer will be described in detail below with reference to Figures 8(b) to (d).

[0042] Referring to Figure 8(b), the first layer of the internal resonant circuit will be described. The first layer of the internal resonant circuit comprises a wiring section 410, lower electrodes 400, 402, 404, 406, and contact pads 412, 414, 416. The wiring section 410 constitutes the inductor L3 shown in Figure 7(b). The lower electrodes 400, 402, 404, 406 constitute the lower electrodes of the capacitors C11, C12, C21, C22 shown in Figure 7(b).

[0043] Lower electrodes 400 and 402 are connected via wiring 401, and lower electrodes 404 and 406 are connected via wiring 405. A contact pad 412 is provided on lower electrode 402, and a contact pad 414 is provided on lower electrode 404. Furthermore, one end of wiring section 410 is connected to lower electrode 402 via wiring 418, and the other end of wiring section 410 is connected to contact pad 416.

[0044] In this example, the contacts between the first and third layers have an alignment margin in the printing direction (circumferential direction). Therefore, the first layer has contact pads 412, 414, and 416 that are slightly larger than those of the third layer which overlaps it.

[0045] Referring to Figure 8(c), the second layer of the internal resonant circuit will be described. The second layer of the internal resonant circuit comprises three mutually separated insulating layers 420, 422, and 424. Insulating layer 420 is formed to cover the lower electrodes 400, 402, wiring 401, part of the contact pad 412, and part of the wiring 418 shown in Figure 8(b). Insulating layer 422 is formed to cover part of the wiring section 410 and contact pad 416 shown in Figure 8(b). Furthermore, insulating layer 424 is formed to cover part of the lower electrodes 404, 406, wiring 405, and contact pad 414 shown in Figure 8(b). In addition, part of the contact pad 412 is exposed from the insulating layer between insulating layer 420 and insulating layer 422, and contact pads 414 and 416 are exposed from the insulating layer between insulating layer 422 and insulating layer 424. This makes it possible to connect the first layer and the third layer via contact pads 412, 414, and 416.

[0046] Referring to Figure 8(d), the third layer of the internal resonant circuit will be described. The third layer of the internal resonant circuit comprises four rectangular upper electrodes 430, 432, 434, 436 and wiring 431, 433, 435, 438, 440.

[0047] The upper electrodes 430, 432, 434, and 436 constitute the upper electrodes of capacitors C11, C12, C21, and C22 shown in Figure 7(b), respectively. Upper electrodes 430 and 432 are formed on the insulating layer 420 and connected via wiring 431. Upper electrodes 434 and 436 are formed on the insulating layer 424 and connected via wiring 435. Upper electrodes 432 and 434 are also connected via wiring 438 that passes over the insulating layer 422. Furthermore, wiring 440 is connected to the contact pads 412 and 414 of the first layer.

[0048] In this way, by stacking the first to third layers described above, an internal resonant circuit according to the second modified example can be constructed. Furthermore, even if the patterns of the first layer and the third layer are reversed, an internal resonant circuit similar to that of this embodiment can be realized.

[0049] Furthermore, when the amount of sample is very small, the thinner and narrower the cylindrical tube 24, the higher the packing density of the sample inside the inductor formed in the cylindrical tube 24. For this reason, it is preferable to have a thin cylindrical tube 24, as long as sufficient rigidity is ensured to maintain the shape of the cylindrical tube 24, because this can improve the detection sensitivity of the NMR spectrum.

[0050] When the internal resonant circuit of this disclosure is inserted into a sample tube for general NMR measurement and used for measurement, if the internal resonant circuit moves inside the sample tube, the axis of rotation may wobble, as explained with reference to Figures 2 and 3, making it impossible to rotate the sample tube at high speed. In such cases, it is preferable to insert a spacer between the sample tube and the internal resonant circuit. This suppresses the movement of the internal resonant circuit inside the sample tube, making it possible to rotate the sample tube at a higher speed.

[0051] The size of the cylindrical tube 24 (e.g., outer diameter, inner diameter, and length), the linewidth and film thickness of the first to third layers depend on the NMR spectrometer and the size of the sample tube used. NMR sample tubes come in outer diameters (inner diameters) of 8.0 mm (6.4 mm), 3.2 mm (2.2 mm), 1.0 mm (0.5 mm), etc. For example, when using a sample tube with an outer diameter (inner diameter) of 3.2 mm (2.2 mm), the outer diameter may be 0.5 to 2.0 mm, the length 1.5 to 2.0 mm, and the thickness 0.05 to 0.15 mm.

[0052] The capacitor area, interlayer insulation thickness, inductor linewidth, and number of turns all depend on the measurement frequency (magnetic field strength) of the NMR spectrometer used. For example, using a 600 MHz NMR spectrometer... 1 When measuring H, it is necessary to adjust the inductor and capacitor so that the internal resonant circuit resonates with a 600 MHz electromagnetic field. For example, if the inductor is 5 mm long and has 5 turns, the self-inductance will be approximately 7.5 nH, and a capacitor of approximately 9.4 pF will need to be connected (the length of the inductor is p in Figure 5(a)). If a resin material (with a dielectric constant of 2.0-2.5) usable with general printing technology is used as the interlayer insulating film, this can be achieved with a capacitor having parallel electrodes of approximately 2 mm x 2 mm.

[0053] As described above, the internal resonant circuit according to this embodiment comprises an inductor formed along the surface of a first cylindrical shape having a central axis (the outer surface of the cylindrical tube 24), and a capacitor formed along the surface of a second cylindrical shape having the same central axis (the outer surface of the cylindrical tube 24). The inductor and the capacitor are electrically connected to each other, forming a closed loop. In this embodiment, since the inductor and the capacitor are formed along a coaxial cylindrical shape, it becomes easier to balance the weight around the central axis.

[0054] Therefore, by inserting the internal resonant circuit according to this embodiment into the sample tube during NMR measurement and using it in MACS-NMR, it becomes easier to balance the weight around the rotation axis and along the long axis of the sample tube. As a result, fluctuations in the rotation of the sample tube during rotation are suppressed, and the sample tube can be rotated stably at the rotation speed required for measurement. The lower and upper limits of the rotation speed of the sample tube in an NMR apparatus vary depending on the size of the probe, etc., but higher rotation speeds can increase detection sensitivity. By using the internal resonant circuit according to this embodiment, fluctuations in the rotation of the sample tube can be suppressed within the range from the lower limit to the upper limit of the NMR apparatus used. As a result, detection sensitivity can be increased and measurement time can be shortened in MACS-NMR measurements.

[0055] Furthermore, in MAS-NMR, the sample tube may be cooled, and the first conductive layer, insulating layer, and second conductive layer constituting the internal resonant circuit must have sufficient cooling resistance to prevent peeling or other damage under cooled conditions. Internal resonant circuits fabricated by the printing or photolithography methods described later have the advantage of possessing such cooling resistance.

[0056] [Manufacturing method for internal resonant circuits] Next, a method for manufacturing an internal resonant circuit according to one embodiment of the present disclosure will be described. The method for manufacturing an internal resonant circuit according to the present embodiment is a method for manufacturing an inductor and a capacitor, which includes a first forming step of forming a first conductive layer along the outer surface of a cylindrical tube on the outer surface of a cylindrical tube, a second forming step of forming an insulating layer on the surface of the first conductive layer formed in the first forming step, and a third forming step of forming a second conductive layer on the surface of the insulating layer formed in the second forming step.

[0057] Electronic circuits with such a layered structure can be fabricated using general photolithography techniques as well as printing techniques. To minimize damage to the printing target (e.g., cylindrical tubes), inkjet printing, which can form a thin film without contact, and various types of offset printing, which print by using a soft, rubber-like transfer roller in contact with the printing target, can be used. Here, various types of offset printing refer to general offset printing, as well as inkjet offset printing, screen offset printing, gravure offset printing, and reverse offset printing. Furthermore, rotary screen printing, a typical printing method for cylindrical surfaces, can also be used.

[0058] [Manufacturing method for internal resonant circuits using printing technology (printing method)] Figures 9(a) to 9(c) show examples of patterns for fabricating an internal resonant circuit, and Figures 10(a) to 10(c) show modified versions thereof. In each figure, direction a corresponds to the circumferential direction of the cylindrical tube, and direction b corresponds to the longitudinal direction of the cylindrical tube. When the diameter of the cylindrical tube 24 is φ, the length d in direction a satisfies the relationship d = πφ + α. Here, α is a term that corrects for expansion and contraction due to printing. For example, in screen printing, the pattern expands due to the slight expansion of the printing plate, so α takes a negative value, and in gravure offset printing, the pattern shrinks due to the expansion of the transfer roller, so α takes a positive value. In cases where the shape can be transferred directly, such as in photolithography, α is 0.

[0059] When forming the first layer, a pattern like that shown in Figure 9(a) or Figure 10(a) can be used. More specifically, the pattern for forming the first layer includes a wiring pattern 510, a lower electrode pattern 512 connected to one end of the wiring pattern 510, and a connecting wire pattern 514 connected to the other end of the wiring pattern 510, as shown in Figure 9(a). The wiring pattern 510 corresponds to the wiring 310, the lower electrode pattern 512 corresponds to the lower electrode 314, and the connecting wire pattern 514 corresponds to the connecting wire 312.

[0060] In the pattern shown in Figure 9(a), the length of the wiring pattern 510 in the a-direction is 6d, and the length of the lower electrode pattern 512 in the a-direction is d. By rolling the cylindrical tube six times in the a-direction on the pattern shown in Figure 9(a), it becomes possible to transfer the wiring pattern that has been rolled six times and the electrode pattern that covers the entire circumference of the cylindrical tube onto the surface of the cylindrical tube.

[0061] When the sides of the cylindrical internal resonant circuit are unfolded, the shape of the internal resonant circuit becomes as shown in Figure 10(a), and this shape can be used as a mask pattern for photolithography. Specifically, this mask pattern has a wiring pattern 550, a lower electrode pattern 552 connected to one end of the wiring pattern 550, and a connecting line pattern 554 connected to the other end of the wiring pattern 550.

[0062] Printing is prone to stretching and shrinking in both the vertical and horizontal directions, making it very difficult to form an inductor using the pattern shown in Figure 10(a). Therefore, a pattern like that shown in Figure 9(a) can be used instead.

[0063] The second layer is formed to cover everything except the connection wires of the first layer, so an insulating layer pattern 520 as shown in Figure 9(b) may be used. However, the second layer only needs to be configured to insulate the wiring of the inductor while forming the insulating layer of the capacitor, so it can take the shape shown in Figure 10(b). Specifically, the pattern of the second layer can take the shape shown in Figure 10(b), which includes an insulating layer pattern 560 that forms the insulating layer of the capacitor and an insulating layer pattern 562 for insulating the wiring of the first layer from the connection wires of the third layer.

[0064] The third layer may use a pattern like that shown in Figure 9(c) to form the upper electrode of the capacitor and the connecting line connecting the capacitor and the inductor. The pattern shown in Figure 9(c) includes an upper electrode pattern 530 that constitutes the upper electrode of the capacitor and a connecting line pattern 532 connected to the upper electrode pattern 530.

[0065] Furthermore, when using printing technology to form these first to third layers, depending on the printing method used, there may be orientations that are difficult to form, so it is preferable to deform the shape to avoid these orientations. For example, in gravure offset printing, it is very difficult to form straight lines perpendicular to the printing direction, so the connecting line pattern 532 in Figure 9(c) may be made diagonal (i.e., in a direction tilted from direction b). For example, as shown in Figure 10(c), this problem can be solved by connecting the diagonal connecting line pattern 572 to the upper electrode pattern 570.

[0066] Furthermore, alignment markers (for example, marker 516 shown in Figure 9(a)) may be provided in the pattern of each layer as needed. The alignment markers should be shaped to be optimal for image recognition of the alignment mechanism mounted on the equipment used in the manufacturing process, thereby improving the alignment accuracy of the layers. These alignment markers may be formed on the cylindrical tube from the beginning, or they may be removed from the cylindrical tube after being transferred to it.

[0067] Here, we will explain the transfer process when using various types of offset printing. In various types of offset printing, the pattern to be printed is received on the surface of the transfer roller by various methods. For example, in inkjet offset printing, the inkjet head draws the pattern on the surface of the transfer roller, and in screen offset and gravure offset printing, the pattern is received on the transfer roller from the screen printing plate or gravure plate. Then, the pattern received on the surface of the transfer roller is transferred to the surface of the cylindrical tube to form each layer.

[0068] As an example of a manufacturing method using various offset printing techniques, an example of manufacturing an internal resonant circuit using gravure offset printing is shown. In this embodiment, the first formation step for manufacturing the internal resonant circuit includes forming a first conductive layer by rolling a cylindrical tube onto the surface of a transfer roller to which a first ink, which will become the first conductive layer, is attached, thereby transferring the first ink to the outer surface of the cylindrical tube. The second formation step includes adhering the second ink to the surface of the first conductive layer by rolling a cylindrical tube, on which the first conductive layer and the insulating layer are formed, onto the surface of a transfer roller to which a second ink, which will become the insulating layer, is attached. Furthermore, the third formation step includes adhering the third ink to the surface of a transfer roller to which a third ink, which will become the second conductive layer, is attached, by rolling a cylindrical tube, on which the first conductive layer and the insulating layer are formed, thereby adhering the third ink.

[0069] The formation processes for the first, second, and third layers will be described with reference to Figures 11(a) to (c). Gravure offset printing is performed by filling the recesses of a gravure plate having a predetermined pattern with ink, receiving the ink filled in the recesses with a transfer roller, and transferring the received ink to a cylindrical tube which is the object to be printed. In this embodiment, the pattern of the gravure plate is a pattern corresponding to the first conductive layer in the first formation process, a pattern corresponding to the insulating layer in the second formation process, and a pattern corresponding to the second conductive layer in the third formation process.

[0070] Figure 11(a) is a diagram illustrating the process of filling a gravure plate 44 having a pattern with a predetermined ink. First, the blade 40 and gravure plate 44 shown in Figure 11(a) are prepared. The blade 40 is a component with a blade-shaped tip, and the gravure plate 44 includes recesses 47 having a predetermined pattern. In Figure 11(a), the gravure plate 44 is shown as a plate-shaped component, but a roll-shaped plate may also be used.

[0071] The ink 42 may be an ink containing a conductive material or resin. For example, in the first and third forming steps, the ink may be, for example, a silver paste, and in the second forming step, the ink may be, for example, a resin paste. The viscosity of the ink 42 may be any viscosity suitable for the various printing technologies used. For example, when using gravure offset printing, it may have a high viscosity of about 1000 to 3000 cps.

[0072] First, as shown on the left side of Figure 11(a), with the required amount of ink 42 on the surface of the gravure plate 44, the blade 40 is moved while its tip is in contact with the surface of the gravure plate 44, thereby leveling the surface of the gravure plate 44 with the blade 40. As a result, as shown on the right side of Figure 11(a), the recesses 47 of the gravure plate 44 are filled with ink 48. The leveling action of the blade 40 can be performed multiple times to ensure proper filling. In addition, filling can be performed at different angles to the gravure plate 44. For example, it is possible to fill 2-3 times in a direction perpendicular to the printing direction, and then fill 2-3 times in the printing direction.

[0073] Here, it is preferable to press the blade 40 against the gravure plate 44 and apply filling pressure to the blade 40 while filling the recesses 47 of the gravure plate 44 with ink. The amount of filling pressure is preferably such that no ink remains on the surface of the gravure plate 44 other than the recesses 47.

[0074] Furthermore, the speed at which the blade 40 is moved (also called the "filling speed") may be a speed at which the ink is more likely to undergo dilatancy (for example, around 10-30 mm / s). When dilatancy occurs, the viscosity of the ink decreases, making it possible to fill the recesses 47 with ink even if the pattern shape of the recesses 47 is fine.

[0075] Figure 11(b) is a diagram illustrating the process of transferring the ink filled into the gravure plate 44 to the transfer roller 50.

[0076] The transfer roller 50 used in gravure offset printing has a cylindrical metal cylinder 52 and rubber 53 provided around the metal cylinder 52, and rotates in the printing direction and the opposite direction. The rubber 53 may be a low-surface-energy silicone rubber such as PDMS (dimethylpolysiloxane), and a rubber with a thickness of 0.4 to 0.6 mm and a rubber hardness of approximately 45 (Shore A), which is commonly used in gravure offset printing, can be used. Alternatively, it may be used in lamination with a sponge-like underrubber. Alternatively, a thick and soft transfer roller called a soft blanket may be used, which has a rubber thickness of 10 to 30 mm and a rubber hardness (Shore A) of 1 or less (Asker C hardness of 5 to 20).

[0077] As shown in Figure 11(b), when the surface of the transfer roller 50 is in contact with the surface of the gravure plate 44 which is filled with ink 48 having a predetermined pattern, and the transfer roller 50 is rolled while being pressed against the gravure plate 44, the ink that was filled in the recesses 47 of the gravure plate 44 is received by the surface of the transfer roller 50.

[0078] At this time, the speed at which the transfer roller 50 is rolled (also called the "receiving speed") may be about the same as the filling speed, for example, 10 to 100 mm / s, or more specifically, about 30 mm / s. Also, the pressure applied to press the transfer roller 50 against the gravure plate 44 (also called the "receiving pressure") is about 0.05 to 0.6 mm when using rubber for normal gravure offset printing, and about 10 to 35 mm when using a soft blanket, although this varies depending on the thickness. In this specification, the magnitude of the pressure is expressed in terms of the pressing distance. The pressing distance is the distance from which the transfer roller is pressed towards the gravure plate 44, starting from a state where the undeformed transfer roller and the surface of the gravure plate are in contact. Thus, in general printing presses, printing pressure is often expressed not as actual pressure, but as the distance generated by pressing or pressing, and is sometimes expressed as pressing distance, nip width, etc.

[0079] Figure 11(c) illustrates the process of transferring ink to the surface of the cylindrical tube 24. In Figures 11 and 12, the cylindrical tube 24 and the ink before and after transfer are shown larger than their actual size to make each process easier to see.

[0080] As shown in Figure 11(c), the outer surface of the cylindrical tube 24 is brought into contact with the transfer roller 50 that has received the ink. In this state, the cylindrical tube 24 is rolled circumferentially on the surface of the transfer roller 50, thereby transferring the ink 54 from the surface of the transfer roller 50 to the outer surface of the cylindrical tube 24. In the transfer process in various offset printing methods, printing pressure is often required, so it is preferable to print by pressing the cylindrical tube 24 against the transfer roller 50. In general gravure offset printing, if the pressing distance during transfer and acceptance is the same, the deformation of the pattern (such as expansion and contraction) will be reduced. However, when using a soft blanket, it is difficult to make the pressing distance during transfer the same as that during acceptance. Therefore, the expansion and contraction of the pattern can be controlled by the α term in d = πφ + α, as explained with reference to Figures 9(a) to (c).

[0081] Figure 12 shows a modified example of a method for transferring a pattern to a cylindrical tube 24. A central axis 56 is provided inside the cylindrical tube 24, which is the object to be printed on, to fix the object to be printed on. When the transfer roller 50, which has a predetermined pattern on its surface, is rotated in contact with the outer surface of the cylindrical tube 24, ink can be transferred to the surface of the cylindrical tube. In particular, since the transfer roller 50, whose surface is made of rubber, has tackiness (adhesion), the cylindrical tube also rotates when the transfer roller rotates, so a printing mechanism with a linked rotation structure can be adopted. Linked rotation refers to the movement of two objects in contact with each other, where if one object moves, the other object also moves along with it.

[0082] When an internal resonant circuit is fabricated using printing technology, the ink is dried or fired after printing, if necessary. The conditions for drying or firing the ink (e.g., temperature and time) can be appropriately set depending on the type of ink used. For example, if the ink is a silver paste, it is preferable to fire it at a temperature of 80-150°C for 10-60 minutes. This causes the silver paste to solidify and develop conductivity, forming a conductive layer (first conductive layer or second conductive layer). Similarly, resin pastes that form an insulating layer are also preferably fired at a temperature of 80-200°C for about 10-60 minutes. Alternatively, instead of firing immediately after printing, a leveling period of about 10-60 minutes may be provided.

[0083] The inventors formed an internal resonant circuit on the surface of a cylindrical tube using the gravure offset printing method described above. Then, they inserted the cylindrical tube into the sample tube of a MACS-NMR apparatus and rotated the sample tube, confirming that it could rotate at a rotational speed of at least 3 kHz. Thus, according to this embodiment, the sample tube can be rotated stably at a high rotational speed during MACS-NMR measurement.

[0084] In the above embodiment, we mainly described an example in which the outer diameter of the cylindrical shape in which the inductor is formed (the first cylindrical shape) and the outer diameter of the cylindrical shape in which the capacitor is formed are the same. However, the embodiment is not limited to this, and the outer diameters of the first cylindrical shape and the second cylindrical shape may be different from each other, as long as the first cylindrical shape and the second cylindrical shape have the same central axis.

[0085] [Manufacturing method for internal resonant circuits using photolithography (photolithography method)] The internal resonant circuit described herein can be fabricated using photolithography in addition to the printing method described above. Generally, photolithography is considered a patterning technique for fabricating wiring on planar substrates. However, for curved surfaces and three-dimensional surfaces, a technique called film exposure is used to perform photolithographic patterning, which allows for the fabrication of wiring on the surface of cylindrical tubes and the manufacture of inductors, capacitors, and the like. Here, a method for fabricating an internal resonant circuit having the same circuit configuration as the circuit diagram shown in Figure 4 using photolithography by film exposure will be explained with reference to Figures 13 to 17. Regardless of the fabrication method, the appearance of the internal resonant circuit will be almost the same. An internal resonant circuit having the circuit configuration shown in the circuit diagram of Figure 4 will have the appearance shown in Figure 5(a). An internal resonant circuit fabricated by photolithography will have the same appearance as an internal resonant circuit fabricated using printing technology, and its cross-section will also be the same. Figures 13 to 17 show the region corresponding to the cross-section AA' shown in Figure 5(a), with a portion omitted.

[0086] The method for fabricating an internal resonant circuit using photolithography is similar to the method for manufacturing an internal resonant circuit using printing technology described above, and consists of a first formation step for forming a first conductive layer, a second formation step for forming an insulating layer, and a third formation step for forming a second conductive layer.

[0087] The first formation step will be explained with reference to Figures 13(a) to (f). In the first formation step, a metal layer 600 of a desired thickness is first formed on the outer surface of the cylindrical tube 24 by processes such as sputtering, vapor deposition, or plating (Figure 13(a)). The material of the metal layer 600 is not particularly limited as long as it is a metal that can be formed by each process when using vacuum deposition processes such as sputtering and vapor deposition. However, considering the subsequent processes, the material of the metal layer 600 is preferably a metal that can be wet etched, specifically gold, silver, copper, aluminum, tungsten, molybdenum, etc. Also, since the vacuum deposition process is anisotropic, in order to form a uniform metal layer 600 on the surface of the cylindrical tube 24, it is preferable to rotate the cylindrical tube 24 during deposition while forming the metal layer 600. Furthermore, the deposition process is not limited to a vacuum deposition process; a copper thin film or the like can also be formed on polyimide by electrolytic or electroless plating, similar to when manufacturing a general FPC (Flexible Printed Circuits).

[0088] When forming the metal layer 600 using a vacuum deposition process, the cylindrical tube 24 must have durability against the processing temperature of the vacuum deposition process. Furthermore, when forming the metal layer 600 using a plating process, the cylindrical tube 24 must have chemical resistance. Therefore, it is preferable that the cylindrical tube 24 be made of a heat-resistant and chemical-resistant material, such as metal oxides like titanium oxide and zirconium oxide, or a heat-resistant resin known as an engineering plastic, such as PEEK (polyether ether ketone) and PI (polyimide).

[0089] Next, the resist is applied to the entire surface of the metal layer 600 to form a resist layer 610 (Figure 13(b)). The resist used to form the resist layer 610 can be a peelable positive or negative resist commonly used in semiconductor processes. In the process of forming a resist layer on a plane, the resist is applied using the spin coating method, but when applying the resist to an object with a three-dimensional shape, the dip coating method (pulling method) may be used. The dip coating method allows for adjustment of the desired resist layer thickness by adjusting the viscosity of the resist and the pulling speed. Furthermore, if it is difficult to uniformly apply the resist to a three-dimensional shape, a DFR (dry film resist), which is in sheet form and can be used simply by attaching it to the surface, can be used. Similarly, a method may be used in which a resist coating film is formed on the surface of a peelable sheet, and the sheet is wrapped around the surface of the cylindrical tube 24 to transfer the resist layer 610 to the surface of the metal layer 600.

[0090] Next, film exposure is performed to expose the resist layer 610 (Figure 13(c)). Film exposure is a method used for patterning curved and three-dimensional surfaces. For example, an exposure film 620, which serves as a mask, is wrapped around a cylindrical tube 24 on which the metal layer 600 and the resist layer 610 are formed, and exposed from above to expose the resist layer 610.

[0091] Here, the pattern of the light-shielding film 624 of the exposure film 620 used is such that, when a positive resist is used, the black pattern formed on the surface of the cylindrical tube 24 is the light-shielding pattern, and the other parts are transparent. When light is shone on the exposure film 620, the light passes through the transparent parts of the light-shielding film 624, and the resist layer 610 in those parts is exposed. On the other hand, the resist layer 610 in the light-shielding pattern parts remains unexposed. Furthermore, while a single-wavelength light source used in normal exposure may be used for exposure, it is more common to use a light source for film exposure that includes a certain range of wavelengths to expose curved surfaces and three-dimensional objects. If the direction of irradiation of the light source is limited to one direction, the resist layer 610 may be exposed while rotating the cylindrical tube 24 using a rotation mechanism, similar to film deposition.

[0092] Thus, a method called film exposure involves using an exposure film, which is a flexible, transparent film that can be wrapped around or conformed to a three-dimensional object and has a desired light-shielding pattern, to wrap around an object coated with a resist, and exposing it while it is in close contact with the surface of the object. If the surface of the object to be exposed has a complex shape, the exposure film can be deformed using a heat deformation machine or the like to process the exposure film so that it adheres closely to the object to be exposed, and then exposed. In this embodiment, since the object to be exposed is a cylindrical tube 24, a highly flexible sheet-like exposure film 620 is used.

[0093] Furthermore, when exposing the resist layer 610 with light from a light source, an anti-reflective coating (BARC) may be formed in advance to suppress the effect of reflected light on the metal layer 600 on the surface of the cylindrical tube 24. The type of anti-reflective coating can be selected from commercially available products, depending on the type of light source used.

[0094] Next, the photosensitive resist layer 610 is developed (Figure 13(d)). Development is performed using a developer suitable for the applied resist layer 610. After development, the resist layers 610a to 610d remain in the same shape as the pattern of the first conductive layer formed on the surface of the cylindrical tube 24, and in this embodiment, in the same shape as the pattern of the first conductive layer shown in Figure 5(b).

[0095] Next, the metal layer 600 in the area where the resist layer 610 has been removed is etched to form a first conductive layer (metal layers 600a to 600d) having a desired pattern (Figure 13(e)). Since it is difficult to apply dry etching to remove thin films formed on curved surfaces and three-dimensional objects, it is preferable to use wet etching. When etching the metal layer 600 by wet etching, the etching solution can be aqua regia if the metal layer 600 is gold, an aqueous copper chloride solution if it is copper, an aluminum mixed acid solution if it is aluminum, or a mixture of hydrogen peroxide solution and an aqueous ammonium solution if it is tungsten or molybdenum.

[0096] Finally, the resist layers 610a to 610d remaining on the metal layers 600a to 600d are removed using a stripping solution suitable for the resist used (Figure 13(f)). As a result, metal layers 600a to 600d with the desired pattern are formed on the outer surface of the cylindrical tube 24.

[0097] Next, the second formation step for forming the insulating layer will be explained with reference to Figures 14(a) to 14(f). In the second formation step, an insulating layer 630 having insulating properties is formed on the surface of the first conductive layer (metal layers 600a to 600d) using methods such as vacuum deposition and solution deposition (Figure 14(a)). Examples of vacuum deposition methods include forming polyparaxylene (parylene), a paraxylene-based polymer, by vapor deposition, or forming silicon dioxide by sputtering. Among vacuum deposition methods, the CVD method has the advantage of being able to form an insulating layer with a denser film quality.

[0098] Furthermore, an insulating layer can be formed by applying a liquid composition, obtained by dissolving a resin (polymer) such as polyimide, phenolic resin, or epoxy resin in a solvent, using a coating device such as a dispenser or spray coater. Depending on the material of the insulating layer to be applied, the coated film of the liquid composition can be cured after application by drying, heating, or exposure treatment.

[0099] Next, the formed insulating layer 630 is patterned to the shape of the insulating layer 320 shown in Figure 5(c). In this patterning, a resist layer 640 is formed on the upper surface of the insulating layer 630, similar to the first formation step described above (Figure 14(b)). Then, the resist layer 640 is exposed using an exposure film 650 having a transparent film 652 and a light-shielding film 654 (Figure 14(c)), and the resist layer 640 is developed (Figure 14(d)). Next, the insulating layer 630 is etched (Figure 14(e)) to remove the resist layer 640 (Figure 14(f)). This allows the insulating layer 632 having the desired pattern to be formed.

[0100] Here, the insulating layer 632 produced in the second formation step is formed in such a way that, as explained with reference to Figure 5(c), it mainly exposes only the connecting wire 312 of the first conductive layer, while covering the other lower electrodes 314 and wiring portions 310a to 310f (Figure 6(a)). Therefore, the insulating layer 632 can be formed using other methods, such as using a permanent resist or the lift-off method, as shown below.

[0101] A material called a permanent resist can also be used to form an insulating layer. The method for forming an insulating layer using a permanent resist will be explained with reference to Figures 15(a) to 15(c). The second insulating layer is an exposure-developable material called a "permanent resist" or "photosensitive permanent film". The permanent resist is a liquid or sheet-like polymer insulator. First, as shown in Figure 15(a), a permanent resist 700 is applied to the surface of a cylindrical tube 24 on which the first conductive layer (metal layers 600a to 600d) has been formed. Next, the permanent resist 700 is exposed using an exposure film 710 having a transparent film 712 and a light-shielding film 714 with a desired pattern (Figure 15(b)). Then, the permanent resist 700 is developed using a developer (Figure 15(c)). This allows for the formation of an insulating layer 702 with a desired pattern.

[0102] Permanent resists are often photocurable resins. Therefore, as shown in Figure 15(b), the light-shielding pattern of the light-shielding film 714 of the exposure film 710 is formed so that light is shielded in the areas where the permanent resist is to be removed, and light is transmitted in the areas where the permanent resist remains. In this disclosure, either a positive resist or a negative resist may be used as the permanent resist.

[0103] The method for forming an insulating layer using the lift-off method will be explained with reference to Figures 16(a) to (c). First, a resist layer 720 is formed in the region where the insulating layer will not be formed (Figure 16(a)). This resist layer 720 is formed of a material that can be removed later and is called a residual film or sacrificial layer. An insulating layer 730 is formed on the resist layer 720 and the first conductive layer (Figure 16(b)). Next, by removing the resist layer 720, a portion of the insulating layer 730 formed on it is also removed, and an insulating layer 732 with the desired pattern can be formed (Figure 16(c)).

[0104] If high dimensional accuracy is not required for the exposure of the connecting wires 312, adhesive tape can be used instead of the resist layer 720, for example. Specifically, adhesive tape can be applied to the connecting wires 312 before forming the insulating layer 730 by a vacuum deposition or solution deposition process, and the adhesive tape can be peeled off after the insulating layer 730 is formed, thereby exposing the connecting wires 312 and forming an insulating layer 732 with the desired pattern.

[0105] Referring to Figures 17(a) to (f), the third formation step for forming the second conductive layer will be explained. In the third formation step, a metal layer 660 constituting the second conductive layer is formed on the first conductive layer (for example, the metal layer 600d) and the insulating layer 632 using a vacuum deposition method (Figure 17(a)).

[0106] The metal layer 660 formed in the third formation step may be the same metal as the first conductive layer, or it may be a different metal. When the second conductive layer is made of a different metal than the first conductive layer, the etching solution used in wet etching will be different from that used for the first conductive layer. Therefore, when the second conductive layer is made of a different metal than the first conductive layer, there is an advantage that the metal layer formed in the first formation step is not significantly damaged during the wet etching in the third formation step.

[0107] Taking advantage of the wet etching selectivity of this metal, a first or second conductive layer may be formed in a two-layer structure and used as an etching stop layer. For example, the first conductive layer may be formed of aluminum, and the second conductive layer may be laminated in two layers of tungsten and aluminum. Here, by forming the tungsten layer much thinner than the aluminum, high conductivity can be ensured while preventing damage to the first conductive layer during etching of the second conductive layer.

[0108] Next, the formed metal layer 660 is patterned to the shape of the second conductive layer shown in Figure 5(d). Specifically, similar to the first and second formation steps described above, a resist is applied to the upper surface of the metal layer 660 to form a resist layer 670 (Figure 17(b)). Then, the resist layer 670 is exposed using an exposure film 680 having a transparent film 682 and a light-shielding film 684 having a desired light-shielding pattern (Figure 17(c)). Next, the resist layer 670 is developed (Figure 17(d)). Then, the metal layer 660 is etched (Figure 17(e)), and the resist layer 670 is removed (Figure 17(f)). This makes it possible to form a second conductive layer (metal layer 662) having the desired pattern. Here, Figures 17(a) to (f) are drawings corresponding to the cross-section AA' in Figure 5(a). In the areas shown in Figures 17(d) to (f), it appears that the second conductive layer has not been patterned, but in other areas not shown in Figures 17(d) to (f), the second conductive layer has been patterned.

[0109] During exposure using the exposure film 680 in the third formation step, the surface of the resist layer 670 may become uneven due to the influence of the first and second layers, creating a gap between the exposure film 680 and the resist layer 670, which can result in the pattern edges not being cut sharply. In this case, the gap can be eliminated and the pattern edges can be cut sharply by applying a thin layer of highly light-transmitting resin onto the resist layer 670 and then wrapping the exposure film 680 over it.

[0110] Furthermore, if the resist layer 670 cannot be uniformly applied due to the influence of the first and second layers, it is possible to form the resist layer 670 using a printing method. In addition, if a permanent resist is used for the resist layer 670 for purposes such as protecting the conductive layer, the resist layer 670 formed from the permanent resist itself becomes an insulating layer, so it is not necessary to peel off the resist layer.

[0111] Based on the above, it is possible to fabricate an internal resonant circuit having the pattern shown in Figure 5(a) when the cylindrical tube is unfolded. Furthermore, by adjusting the shape of the pattern, it is also possible to fabricate an internal resonant circuit having the pattern shown in Figure 8(a) through a similar process.

[0112] Methods using photolithography, including a vacuum process, can form metal or insulating layers with higher flatness and density than methods using printing. On the other hand, photolithography makes it difficult to form thick metal layers, making it difficult to reduce the resistance of the internal resonant circuit. To solve these process-related problems, the printing method and photolithography may be combined through the first and third formation steps. For example, by performing the first and third formation steps by printing and the second formation step by photolithography, it is possible to create an internal resonant circuit with a thick metal layer and a highly flat and dense interlayer insulating layer. [Examples]

[0113] The present disclosure will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the following, cylindrical tubes with internal resonant circuits obtained in Examples 1 and 2 will be evaluated in Evaluation Examples 1 to 4 to demonstrate their extremely usefulness as sample tubes for NMR measurement.

[0114] Examples 1-2 (Fabrication of internal resonant circuits by printing method) In Examples 1 and 2, internal resonant circuits were fabricated on the surface of two types of polyimide cylindrical tubes (PIT-S-(1.30) and PIT-S-16) with an inner diameter of 1.3 mm (outer diameter of 1.42 mm) and an inner diameter of 2.0 mm (outer diameter of 2.12 mm) using a printing method. The PIT-S-(1.30) tube with the fabricated internal resonant circuit is referred to as "Resonant Circuit 1" in Example 1, and the PIT-S-16 tube with the fabricated internal resonant circuit is referred to as "Resonant Circuit 2" in Example 2.

[0115] 1. Production of the gravure version To fabricate an internal resonant circuit using gravure offset printing, a gravure plate was first created. First, a pattern for the printing plate was created using a CAD system. Here, patterns for the printing plate to form the patterns of the first to third layers shown in Figures 9(a) to (c) were created. Next, an exposure film was made using this pattern. The exposure film was made by printing the pattern onto a thin plastic film using an office multifunction printer. For the production of the gravure plate, a PG plate (PG500, manufactured by Toray Industries, Inc.), which is a resin plate using a photocurable resin and can produce a gravure plate with a plate depth of 50 μm, was used. The exposure film was placed on top of the resin plate before exposure, exposed for 2 minutes and 30 seconds using a plate-making device (PGP-300, manufactured by Toray Industries, Inc.), developed for 2 minutes and 30 seconds using a developer (PG plate-making developer, manufactured by Mino Group Co., Ltd.) attached to the plate-making device, washed with water, and dried in a dryer attached to the plate-making device. Subsequently, a gravure print was created by performing an additional 5 minutes of exposure in an exposure machine.

[0116] The resin plate used is coated with a photocurable resin. Where light hits it hardens, and where light does not hit it, the developing solution dissolves it, creating a recess. This allows for the creation of gravure plates with a plate depth corresponding to the film thickness of the photocurable resin. Therefore, the exposure film produced has a light-blocking black pattern in Figures 9(a) to (c), with a transparent border.

[0117] 2. Fabrication of internal resonant circuits by printing Next, using a curved surface gravure offset printing press (SBG printing press, manufactured by MT Tech Co., Ltd.), an internal resonant circuit was fabricated by forming a first conductive layer (first layer), an insulating layer (second layer), and a second conductive layer (third layer) on each of two types of polyimide cylindrical tubes (PIT-S-(1.30) and PIT-S-16). Conductive ink (XA3656, manufactured by Fujikura Chemicals Co., Ltd.) was used to form the conductive layer, and insulating ink (XB3291, manufactured by Fujikura Chemicals Co., Ltd.) was used to form the insulating layer.

[0118] First, a gravure plate with the first layer pattern and a cylindrical tube, which was to be printed, were fixed to the printing press. Then, conductive ink was filled into the gravure plate, and the ink was received by a blanket. After receiving the ink, a waiting period of 30 to 60 seconds was allowed, and then the ink received by the blanket was transferred to the surface of the cylindrical tube. After that, it was left to stand for 10 to 30 minutes for leveling, and then baked at 120°C for 30 minutes to form the first layer.

[0119] Next, a gravure plate with the pattern for the second layer and a cylindrical tube with the first layer formed on it were fixed to the printing press. Then, insulating ink was filled into the gravure plate, and the ink was received by a blanket. After receiving the ink, a waiting time of 15 to 45 seconds was allowed, after which the ink received by the blanket was transferred to the predetermined position on the surface of the cylindrical tube. Since alignment is required for printing the second layer and beyond, printing was performed using the alignment mechanism of the printing press. After that, it was left to stand for 10 to 30 minutes for leveling, and then baked at 150°C for 30 minutes to form the second layer.

[0120] Next, a gravure plate with the pattern of the third layer and a cylindrical tube with the first and second layers formed on it were fixed to the printing press. Conductive ink was then filled into the gravure plate, and the ink was received by a blanket. After receiving the ink, a waiting time of 30 to 60 seconds was allowed, and then the ink received by the blanket was transferred to the surface of the cylindrical tube. After that, it was left to stand for 10 to 30 minutes for leveling, and then baked at 120°C for 330 minutes to form the third layer. In this way, the first to third layers were formed using the printing method, and an internal resonant circuit was created.

[0121] Evaluation Example 1 (Magic Angle Rotation Test) To confirm that the internal resonant circuit of this disclosure can rotate stably at high speed without causing a change in weight balance during magic angle rotation, the internal resonant circuit fabricated in Example 2 was placed in a commercially available NMR sample tube and fixed, and a magic angle rotation test was performed. The NMR sample tube used had an outer diameter of 3.2 mm and an inner diameter of 2.2 mm, and the sleeve was made of zirconia. A bench spinner was used for the magic angle rotation test. A bench spinner is a device that checks the stability of the magic angle rotation of the sample tube outside the probe to prevent damage to the sample tube due to poor rotation of the sample tube, or damage to the probe due to contact between the sample tube and the coil inside the probe. Of course, a probe from a commercially available NMR apparatus can also be used for the magic angle rotation test.

[0122] The resonant circuit 1 fabricated in Example 1 was cut to a length of 18 mm to match the length of the NMR sample tube, inserted into the sample tube, and a magic angle rotation test was performed using a bench spinner. As a result, stable magic angle rotation was confirmed at 3 kHz, which is the rotation speed generally required for MAS-NMR. Further increasing the rotation speed, stable rotation with a stability of ±5 Hz was confirmed at rotation speeds of 5 kHz, 7 kHz, 10 kHz, 15 kHz, and 20 kHz.

[0123] Next, when the resonant circuit 2 fabricated in Example 2 was inserted into the same NMR sample tube and a magic angle rotation test was performed, the resonant circuit 2 moved inside the sample tube and could not be rotated. Therefore, a 14 mm wide Teflon® tape was wrapped around the resonant circuit 2 to fill the gap between the resonant circuit 2 and the sleeve of the sample tube, and when it was rotated, stable magic angle rotation at 3 kHz was confirmed. Furthermore, when the rotation speed was increased, stable rotation with a stability of ±5 Hz was confirmed at rotation speeds of 5 kHz, 7 kHz, 10 kHz, 15 kHz, and 20 kHz.

[0124] The specified upper limit for the sample tube rotation speed in the NMR spectrometer for the 3.2 mm probe used in Examples 1 and 2 was 22 kHz. Although the lower limit is not specified, even with highly mobile samples like the standard sample Amandane, which yield sharp signals at low speeds, the sample tube is often used at rotation speeds of 3 kHz or higher. From this, it can be said that by using the resonant circuit described in Examples 1 and 2, fluctuations in the rotation of the sample tube from the lower to upper limits of the rotation speed can be suppressed, enabling MACS-NMR measurements.

[0125] Evaluation Example 2 (Durability test related to cooling resistance and magic angle rotation) Since NMR measurements are sometimes performed at low and cryogenic temperatures, the cooling endurance (cooling resistance) of the internal resonant circuit under repeated cooling conditions was evaluated. Each of the resonant circuit 1 and resonant circuit 2 was subjected to a series of operations: immersion in liquid nitrogen for 1 minute, followed by removal, repeated five times. As a result, no visible changes were observed in the conductive and insulating layers of both resonant circuit 1 and resonant circuit 2. Furthermore, resistance measurements using a digital multimeter also showed no change in resistance values.

[0126] Next, the resonant circuits 1 and 2, which had undergone the cooling test described above, were inserted into NMR sample tubes, and the magic angle rotation test was performed in the same manner as in Evaluation Example 1. As a result, stable rotation at 3 kHz was confirmed. From these results, it was found that no peeling or cracking of the conductive and insulating layers occurred due to cooling, and that resonant circuits 1 and 2 could withstand measurements while being cooled.

[0127] Evaluation Example 3 (Resonance characteristics of inductors and external coils fabricated by printing method) To confirm that the internal resonant circuit fabricated by printing resonates when combined with an externally installed coil (detection coil of the NMR apparatus), only the inductor (coil) portion was cut out from the resonant circuit fabricated by printing, and the resonance characteristics with the external coil were measured. The inductor used was obtained by cutting the capacitor portion from resonant circuit 2 fabricated in Example 2, leaving only the inductor portion, and the electrical resistance at both ends was 5Ω.

[0128] Figure 18(a) shows the appearance of the system used to measure the resonance characteristics, and Figure 18(b) shows the circuit diagram of the measurement system. An inductor 802 of an internal resonant circuit (as described above, with the capacitor section cut off to leave only the inductor section) fabricated on the outer circumference of a cylindrical tube 800 by printing was connected to a variable capacitor 804 (Voltronics, NMAP55HVFSK, 1.1~62.7pF) to form a resonant circuit. A two-turn coupling coil 810 was wound around the outside of the inductor 802, and the inductor 802 and the coupling coil (external coil) 810 were coupled by mutual inductance. The coupling coil 810 was then connected via wiring 812 to terminal 822 of a cable 820 that connects to a network analyzer (E5061A, Agilent Technology, not shown), and the resonance characteristic S11 was measured.

[0129] The measurement results are shown in Figure 18(c). Traces 21 to 24 show the measured resonance characteristics at four different capacitance values, from the minimum value (measured value on the LCR meter: 1.1 pF) to the maximum value (measured value on the same meter: 62.7 pF), respectively. The dotted line represents the ratio of Trace 22 to Trace 21. The wavy baseline is thought to be due to reflection and absorption by the connector and coupling coil 810 themselves.

[0130] The resonant frequency changes in accordance with the change in capacitance of the variable capacitor 804, and the resonance becomes sharper and deeper. The Q value of the entire mutually inductively coupled circuit is about 15, and considering that the stray inductance and capacitance are also of a significant magnitude in a configuration like this measurement, the Q value is sufficiently high, and a sufficient enhancement effect on the NMR signal can be expected.

[0131] Evaluation Example 4 (Simulation Results of Oscillating Magnetic Field Strength) To simulate how much the vibrational magnetic field strength would increase when an internal resonant circuit is actually placed in an NMR spectrometer, we attempted electromagnetic field analysis using the finite element method with multiphysics simulation software (COMSOL Multiphysics®).

[0132] An internal resonant circuit was placed inside the coil of an external NMR spectrometer, and a constant oscillating current was passed through the NMR spectrometer's coil. The distribution of the magnetic flux generated within this circuit was then simulated. Since the coil of the external NMR spectrometer is specific to the NMR probe and its size is not publicly available, a size (such as the diameter of the conductor and the cross-sectional radius of the coil) considered to be close to reality was assumed. To reduce the machine power and time (computational cost) required for the calculation, as shown in Figure 19(a), the internal resonant circuit and the coil 902 for signal detection of the NMR spectrometer were assumed to be coupled as axially symmetric circular circuits, and the periphery of the coils was assumed to be infinite. In addition, the capacitance of the internal resonant circuit was connected to coil 900 as a sizeless element.

[0133] Specifically, the circuit is axially symmetric with the horizontal axis at position 0 as the axis of symmetry, and only its cross-section is shown. Here, coil 902 of the NMR apparatus is a 6-turn conductor with a circular cross-section, and coil 900 of the internal resonant circuit is a 5-turn conductor with a thin rectangular cross-section, mimicking wiring fabricated by printing on a polyimide cylindrical tube. This simulation calculated the interior of a semicircle (a sphere in 3D) that covers these coils 900 and 902. The band-shaped portion outside of it is a layer that simulates infinity. The electrical resistivity of the two coils was calculated using data for bulk copper.

[0134] The simulation results are shown in Figures 19(b) to (d). Figures 19(b) and 19(c) show the simulation results in a cross-section with the coil axis at the left end, when the coil's resonant frequencies are approximately 600 MHz and 600.1 MHz, respectively. Magnetic field lines are shown as solid lines, and the magnitude of the magnetic field is shown in grayscale. It can be seen that the magnetic flux density of the internal coil becomes large (darker color) near the internal coil's resonant frequency of approximately 600 MHz, and above 600.1 MHz, which exceeds the resonant frequency, the distribution changes so that the magnetic flux of the internal coil enters the gap between it and the external coil.

[0135] Figure 19(d) shows the frequency dependence of the magnitude of the magnetic field at the center of the internal resonant circuit for this simulation result. Since the magnetic field within the internal resonant circuit increases rapidly in a narrow range near the resonant frequency, it can be said that the internal resonant circuit disclosed herein exhibits a magnetic field enhancement effect when installed in an NMR apparatus. [Explanation of symbols]

[0136] 20 Detection unit, 24 Cylindrical tube, 26 Internal resonant circuit, 42 Ink, 44 Gravure plate, 50 Transfer roller, 52 Metal cylinder, 53 Rubber, 56 Central axis, 610, 640, 670, 720 Resist layer, 620, 650, 680, 710 Exposure film, 220 Sample tube, 260 Inductor, 262 Capacitor, 310 Wiring section, 310P Metal layer, 314 Lower electrode, 320 Insulating layer, 320P Photosensitive insulating layer, 330 Upper electrode, 514 Connection line pattern, 512 Lower electrode pattern, 530 Upper electrode pattern, 510 Wiring section pattern, 520 Insulating layer pattern, 552 Lower electrode pattern, 570 Upper electrode pattern, 554, 572 Connection wire pattern, capacitors C1-C3, C11, C12, C21, C22, inductors L1-L3.

Claims

1. An inductor formed along the surface of a cylindrical shape having a central axis, The system comprises a capacitor formed along the surface of the cylindrical shape, The inductor and the capacitor are electrically connected to each other, forming a closed loop. The inductor and the capacitor are arranged side by side in the direction of the central axis. The capacitor comprises a first conductive layer formed along the cylindrical surface, an insulating layer formed along the surface of the first conductive layer, and a second conductive layer formed along the surface of the insulating layer. The inductor has a wiring portion formed along the surface of the cylindrical shape, The insulating layer is formed to cover the surface of the wiring portion, The wiring section is electrically connected to a first connecting wire formed to encircle the cylindrical shape. The second conductive layer is electrically connected to the first connecting line via a second connecting line. resonant circuit.

2. The capacitor has a plurality of the second conductive layers formed along the surface of the insulating layer, The plurality of second conductive layers are formed in an order along the circumferential direction of the cylindrical shape. The resonant circuit according to claim 1.

3. The aforementioned resonant circuit is inserted inside the sample tube used for NMR measurement. The center of gravity of the sample tube and the inserted resonant circuit is the same as the center of gravity of the sample tube in which the resonant circuit is not inserted. The sample tube into which the resonant circuit is inserted can rotate stably around its central axis at a rotational speed of 3 to 20 kHz, with the central axis of the sample tube tilted by a magic angle from the direction of the static magnetic field. The resonant circuit according to claim 1.

4. The aforementioned capacitors are multiple, Multiple capacitors are connected in parallel. The resonant circuit according to claim 1.

5. A first forming step of forming a first conductive layer along the outer surface of a cylindrical tube on the outer surface, A second forming step involves forming an insulating layer on the surface of the first conductive layer formed in the first forming step, The process includes a third forming step of forming a second conductive layer on the surface of the insulating layer formed in the second forming step, The first conductive layer, the insulating layer, and the second conductive layer constitute a capacitor. The first conductive layer or the second conductive layer constitutes an inductor. The inductor and the capacitor are electrically connected to each other, forming a closed loop. The inductor and the capacitor are arranged side by side in the direction of the central axis of the cylindrical tube. The first forming step includes a first printing step of printing the first ink pattern onto the outer surface of the cylindrical tube by rolling the cylindrical tube on the surface of a transfer roller to which the first ink pattern that will become the first conductive layer is attached, The second forming step includes a second printing step of printing the pattern of the second ink on the surface of the first conductive layer by rolling a cylindrical tube on which the first conductive layer is formed on the surface of a transfer roller to which the pattern of the second ink that will become the insulating layer is attached, The third forming step includes a third printing step of printing the pattern of the third ink onto the surface of the insulating layer by rolling a cylindrical tube on which the insulating layer is formed on the surface of a transfer roller on which the pattern of the third ink that will become the second conductive layer is attached to the surface, The first ink pattern is printed in the first printing step such that the first conductive layer includes the electrodes of the capacitor and the wiring portion of the inductor, or the third ink pattern is printed in the third printing step such that the second conductive layer includes the electrodes of the capacitor and the wiring portion of the inductor. A method for manufacturing inductors and capacitors.

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