JP5609328B2 - Magnetic field probe - Google Patents

Description

  The present invention relates to a magnetic field probe suitable for use in detecting a magnetic field.

  As a magnetic field probe according to the prior art, a magnetic field detection unit composed of a loop pattern is provided on a substrate, and a transmission line unit composed of, for example, a microstrip line or a strip line is connected to the detection unit. A device in which a capacitor is formed between them is known (for example, see Patent Document 1).

  As another conventional technique, a configuration in which a one-turn coil is formed on a substrate and a capacitor is connected in parallel to the coil is disclosed (for example, see Patent Documents 2 and 3). Furthermore, in order to detect a magnetic field parallel to the substrate, a configuration in which a spiral coil is formed on the substrate is also known (see, for example, Patent Document 4).

JP 2007-187539 A JP 2004-69337 A JP 2007-155597 A JP 2004-198329 A

  By the way, in the magnetic field probe according to Patent Document 1, since a capacitor is connected in series to a coil formed of a loop pattern, a magnetic field can be detected with high sensitivity in the peripheral band of these resonance frequencies. At this time, the capacitor connected in series with the coil functions as a high-pass filter for signals of all frequencies. For this reason, there exists a problem that a sensitivity falls compared with the case where a capacitor | condenser is not provided in frequency bands other than a resonant frequency like the low frequency side, for example.

  Patent Documents 2 and 3 also disclose a magnetic field probe including a coil and a capacitor. However, in these magnetic field probes, a capacitor is provided in parallel in a one-turn coil, and the sensitivity is not improved by series resonance of the coil and the capacitor.

  Further, Patent Document 4 discloses a configuration in which a spiral coil is formed on a substrate and a wiring pattern to be inspected is provided on the substrate. However, the spiral coil disclosed in Patent Document 4 detects a magnetic field parallel to the substrate, and does not detect a magnetic field in the thickness direction of the substrate. In addition to this, the wiring pattern provided on the substrate together with the spiral coil is a magnetic field inspection target, and is not a series connection of the coil and the capacitor.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a magnetic field probe capable of improving sensitivity in a desired frequency band and suppressing reduction in sensitivity in other frequency bands. It is to provide.

In order to solve the above-described problem, a magnetic field probe according to the first aspect of the present invention includes a multilayer substrate in which a plurality of insulating layers are stacked in the thickness direction, and different positions in the thickness direction across the insulating layer among the multilayer substrates. Two or more loop patterns provided in a winding shape, and two loop patterns adjacent in the thickness direction among the two or more loop patterns are disconnected and insulated from each other The two or more loop patterns are formed in substantially the same winding shape .

  According to a second aspect of the present invention, a via hole is provided between the remaining loop patterns except for the two loop patterns constituting the capacitor, and adjacent loop patterns are connected in series to constitute a coil. .

According to the first aspect of the present invention, the two adjacent loop patterns in the thickness direction among the two or more loop patterns constitute a capacitor which is opposed to each other while being disconnected and insulated from each other. At this time, each loop pattern functions as a coil and is in a state of being connected in series with the capacitor, so that a magnetic field can be detected with high sensitivity in the peripheral band of the resonance frequency where the coil and the capacitor resonate in series. Furthermore, in a frequency band other than the resonance frequency, the loop pattern constituting the capacitor functions as a part of the coil, and can output a detection signal such as a voltage corresponding to the magnetic field. For this reason, for example, on the lower frequency side than the resonance frequency, the capacitor does not function as a filter but functions as a part of a coil, and therefore, even when a magnetic field is detected in a frequency band other than the resonance frequency, a decrease in detection sensitivity is suppressed. be able to.
Further, since the two or more loop patterns are formed in substantially the same winding shape, the inductance of the coil can be increased as compared with the case where the loop patterns have different winding shapes. Furthermore, since the loop pattern constituting the capacitor can be superimposed on the loop pattern constituting the coil, even when a magnetic field is detected in a frequency band other than the resonance frequency, the loop pattern constituting the capacitor is used as a part of the coil. It can be made to function, and a decrease in detection sensitivity can be suppressed.

  According to the second aspect of the present invention, the via hole is provided between the remaining loop patterns except between the two loop patterns constituting the capacitor. For this reason, a plurality of loop patterns can be connected in series to form a coil having two or more turns, and the inductance can be increased as compared with a one-turn coil to increase the magnetic field detection sensitivity.

It is a perspective view which shows the magnetic field probe by embodiment of this invention. It is a perspective view which expands and shows the detection part in FIG. 1 in the state which saw through the multilayer substrate. It is explanatory drawing shown in the state which decomposed | disassembled the five loop patterns in FIG. It is an equalization circuit diagram which shows the capacitor | condenser and coil which were provided in the magnetic field probe in FIG. It is a front view which shows the 2nd insulating layer from the surface of the multilayer board | substrate in FIG. 1, and two loop patterns arrange | positioned on the both surfaces. It is a front view which shows the 3rd insulating layer from the surface of the multilayer board | substrate in FIG. 1, and two loop patterns arrange | positioned on the both surfaces. It is a front view which shows the 4th insulating layer from the surface of the multilayer board | substrate in FIG. 1, and two loop patterns arrange | positioned on the both surfaces. It is a front view which shows the 5th insulating layer from the surface of the multilayer substrate in FIG. 1, and two loop patterns arrange | positioned on the both surfaces. It is a front view which shows the 6th insulating layer from the surface of the multilayer substrate in FIG. 1, and one loop pattern arrange | positioned on the surface. In embodiment and a comparative example, it is a characteristic diagram which shows the frequency characteristic of the gain of a magnetic field probe. It is explanatory drawing similar to FIG. 3 shown in the state which decomposed | disassembled five loop patterns of the magnetic field probe by a 1st modification. It is explanatory drawing similar to FIG. 3 shown in the state which decomposed | disassembled the two loop patterns of the magnetic field probe by a 2nd modification.

  Hereinafter, magnetic field probes according to embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  1 to 9 show a magnetic field probe 1 according to an embodiment. The magnetic field probe 1 is housed in a cylindrical case 2 made of, for example, a nonmagnetic insulating material and is electrically connected to the signal processing circuit 3. The signal processing circuit 3 detects a magnetic field generated in the vicinity of the detection unit 19 based on detection signals such as voltage and current generated in the detection unit 19 of the magnetic field probe 1. The magnetic field probe 1 includes a multilayer substrate 4 to be described later, a transmission line unit 13 and a detection unit 19 provided on the multilayer substrate 4.

  The multilayer substrate 4 is formed in a flat plate shape extending in parallel with the X axis direction and the Z axis direction, for example, among the X axis direction, the Y axis direction, and the Z axis direction orthogonal to each other. The multilayer substrate 4 is configured by, for example, stacking six insulating layers 5 to 10 in the Y-axis direction that is the thickness direction. At this time, the multilayer substrate 4 has a width dimension of, for example, about several millimeters with respect to the X-axis direction serving as the width direction, and extends along the Z-axis direction serving as the length direction. It is about.

  Moreover, each insulating layer 5-10 is formed in the layer form, for example using the insulating resin material. And the front-end | tip part 4A of the multilayer substrate 4 is located in the one end side (lower end side in FIG. 1) of the Z-axis direction, and the below-mentioned detection part 19 is provided. On the other hand, the base end side of the multilayer substrate 4 extends toward the other end side in the Z-axis direction (upper end side in FIG. 1).

  Ground electrodes 11 and 12 made of, for example, a conductive metal thin film are provided on the front and back surfaces of the multilayer substrate 4 located on both ends in the Y-axis direction. The ground electrodes 11 and 12 are connected to the ground of, for example, the signal processing circuit 3 and are held at the ground potential, and cover substantially the entire surface of the multilayer substrate 4 except for the front end portion 4A of the multilayer substrate 4.

  As shown in FIGS. 1 and 2, the transmission line unit 13 is provided on the multilayer substrate 4, and connects between a detection unit 19, which will be described later, and the signal processing circuit 3. The transmission line portion 13 has a strip conductor 14 (signal electrode) as an elongated conductor pattern made of, for example, a conductive metal thin film. The transmission line unit 13 is configured by a strip line including a strip conductor 14 and ground electrodes 11 and 12 provided on both surfaces of the multilayer substrate 4. Note that the transmission line unit 13 is not limited to a strip line, and may be configured by, for example, a microstrip line in which one ground electrode is omitted.

  The strip conductor 14 is disposed between the insulating layers 7 and 8, and is located in the center portion of the multilayer substrate 4 in the X-axis direction and extends linearly along the Z-axis. The front end side of the strip conductor 14 extends obliquely toward one side in the X-axis direction, and is electrically connected to a loop pattern 20 described later through a via hole 15 penetrating the insulating layers 6 and 7. .

  On the other hand, the ground electrodes 11 and 12 are electrically connected to a loop pattern 24 described later through the via holes 16 and 17 and the connection pattern 18. The connection pattern 18 is located between the insulating layers 7 and 8 and is disposed in the vicinity of the strip conductor 14. Further, the connection pattern 18 is formed by a conductor pattern similar to the strip conductor 14 and extends in the Z-axis direction. Further, the base end side of the connection pattern 18 is connected to the ground electrodes 11 and 12 through the via holes 16 as through-hole vias penetrating the multilayer substrate 4 in the thickness direction. 9 is connected to the connection portion 24B of the loop pattern 24 through a via hole 17 penetrating through 9.

  As shown in FIGS. 1 to 9, the detection unit 19 includes a coil 28 and a capacitor 29 that are arranged at the front end portion 4 </ b> A of the multilayer substrate 4 and are configured by five loop patterns 20 to 24 described later. .

  The loop pattern 20 is disposed between the insulating layer 5 and the insulating layer 6 and uses an elongated electrode pattern made of a conductive metal thin film having a width W0 of about 50 to 150 [mu] m, for example, as shown in FIG. Thus, it is formed in a substantially rectangular winding shape. One end side of the loop pattern 20 is provided with a connecting portion 20A extending toward the other end side in the Z-axis direction. The connecting portion 20A is electrically connected to the strip conductor 14 through the via hole 15. The loop pattern 20 extends in the X-axis direction over a length dimension L1 of, for example, about 1 to 3 mm, and extends in the Z-axis direction over a length dimension L2 of, for example, about 0.4 to 1.2 mm. Thereby, the loop pattern 20 has a substantially rectangular shape parallel to the XZ plane.

  The loop pattern 21 is disposed between the insulating layer 6 and the insulating layer 7, and as shown in FIGS. 5 and 6, for example, an elongated electrode made of a conductive metal thin film having the same width dimension W0 as the loop pattern 20 It is formed using a pattern. The loop pattern 21 has a rectangular frame shape with a part cut out, and is formed in a substantially rectangular winding shape as the adjacent loop pattern 20. In addition, the loop pattern 21 is disposed such that both ends thereof are separated from each other in the X-axis direction, and extends along the loop pattern 20 from one end side to the other end side. A connecting portion 21A is provided on the other end side of the loop pattern 21, and the connecting portion 21A is electrically connected to an adjacent loop pattern 22 through a via hole 25 described later. Similarly to the loop pattern 20, the loop pattern 21 extends in the X-axis direction over the length dimension L1 and extends in the Z-axis direction over the length dimension L2. Thus, the loop pattern 21 has a substantially rectangular shape parallel to the XZ plane, and faces the loop pattern 20 in the thickness direction with the insulating layer 6 interposed therebetween.

  The loop pattern 22 is disposed between the insulating layer 7 and the insulating layer 8, and as shown in FIGS. 6 and 7, for example, an elongated electrode made of a conductive metal thin film having the same width dimension W0 as the loop pattern 21 It is formed using a pattern. The loop pattern 22 has a rectangular frame shape with a part cut away, and is formed in a substantially rectangular winding shape as the adjacent loop pattern 21. Further, the loop pattern 22 is disposed such that both ends thereof are separated from each other in the X-axis direction, and extends along the loop pattern 21 from one end side toward the other end side.

  On one end side of the loop pattern 22, a connection portion 22 </ b> A is provided at a position facing the connection portion 21 </ b> A of the loop pattern 21. The connecting portion 22A is electrically connected to the connecting portion 21A of the adjacent loop pattern 21 through a via hole 25 described later. On the other hand, a connecting portion 22B is provided on the other end side of the loop pattern 22 so as to be located on the other side in the X-axis direction (right side in FIG. 1) with respect to the connecting portion 22A. The connecting portion 22B is electrically connected to the adjacent loop pattern 23 through a via hole 26 described later.

  Similarly to the loop pattern 21, the loop pattern 22 extends in the X-axis direction over the length dimension L1 and extends in the Z-axis direction over the length dimension L2. As a result, the loop pattern 22 has a substantially rectangular shape parallel to the XZ plane, and faces the loop pattern 21 in the thickness direction with the insulating layer 7 interposed therebetween.

  The loop pattern 23 is disposed between the insulating layer 8 and the insulating layer 9, and as shown in FIGS. 7 and 8, for example, an elongated electrode made of a conductive metal thin film having the same width dimension W0 as the loop pattern 22 It is formed using a pattern. The loop pattern 23 has a rectangular frame shape with a part cut away, and is formed in a substantially rectangular winding shape as the adjacent loop pattern 22. Further, the loop pattern 23 is arranged such that both ends thereof are separated from each other in the X-axis direction, and extends along the loop pattern 22 from one end side to the other end side.

  On one end side of the loop pattern 23, a connection portion 23A is provided at a position facing the connection portion 22B of the loop pattern 22. The connecting portion 23A is electrically connected to a connecting portion 22B of the adjacent loop pattern 22 through a via hole 26 described later. On the other hand, the other end side of the loop pattern 23 is provided with a connection portion 23B located on the other side in the X-axis direction with respect to the connection portion 23A. The connecting portion 23B is electrically connected to the adjacent loop pattern 24 through a via hole 27 described later.

  Similarly to the loop pattern 22, the loop pattern 23 extends in the X-axis direction over the length dimension L1, and extends in the Z-axis direction over the length dimension L2. Thus, the loop pattern 23 has a substantially rectangular shape parallel to the XZ plane, and faces the loop pattern 22 in the thickness direction with the insulating layer 8 interposed therebetween.

  The loop pattern 24 is disposed between the insulating layer 9 and the insulating layer 10 and, as shown in FIGS. 8 and 9, for example, an elongated electrode made of a conductive metal thin film having the same width dimension W0 as the loop pattern 23 It is formed using a pattern. The loop pattern 24 has a rectangular frame shape with a part cut away, and is formed in a substantially rectangular winding shape as the adjacent loop pattern 23. In addition, the loop pattern 24 is disposed such that both ends thereof are separated from each other in the X-axis direction, and extends along the loop pattern 23 from one end side to the other end side.

  On one end side of the loop pattern 24, a connection portion 24A is provided at a position facing the connection portion 23B of the loop pattern 23. The connecting portion 24A is electrically connected to a connecting portion 23B of the adjacent loop pattern 23 through a via hole 27 described later. On the other hand, a connection portion 24B extending toward the other end side in the Z-axis direction is provided on the other end side of the loop pattern 24. The connection portion 24B is electrically connected to the connection pattern 18 through the via hole 17. Yes.

  Similarly to the loop pattern 23, the loop pattern 24 extends in the X-axis direction over the length dimension L1, and extends in the Z-axis direction over the length dimension L2. Thereby, the loop pattern 24 has a substantially rectangular shape parallel to the XZ plane, and faces the loop pattern 23 in the thickness direction with the insulating layer 9 interposed therebetween.

  As described above, the loop patterns 20 to 24 are formed in substantially the same winding shape, and are disposed at substantially the same position with respect to the X-axis direction and the Z-axis direction of the multilayer substrate 4. Thereby, the loop patterns 20 to 24 overlap each other in the thickness direction over substantially the entire length excluding the connecting portions 20A and 24B.

  The via hole 25 is located between the loop patterns 21 and 22 in the thickness direction, penetrates the insulating layer 7, and is formed by covering its inner wall with a conductive material such as a metal material. The via hole 25 is disposed at a position corresponding to the connection portion 21A of the loop pattern 21 and the connection portion 22A of the loop pattern 22, and electrically connects the loop pattern 21 and the loop pattern 22 in series.

  The via hole 26 is located between the loop patterns 22 and 23 in the thickness direction, penetrates the insulating layer 8, and is formed in the same manner as the via hole 25. The via hole 26 is disposed at a position corresponding to the connection portion 22B of the loop pattern 22 and the connection portion 23A of the loop pattern 23, and electrically connects the loop pattern 22 and the loop pattern 23 in series.

  The via hole 27 is located between the loop patterns 23 and 24 in the thickness direction, penetrates the insulating layer 9, and is formed in the same manner as the via hole 25. The via hole 27 is disposed at a position corresponding to the connection portion 23B of the loop pattern 23 and the connection portion 24A of the loop pattern 24, and electrically connects the loop pattern 23 and the loop pattern 24 in series.

  As a result, the loop patterns 21 to 24 are connected to each other in series using the via holes 25 to 27, and constitute a coil 28 having approximately four turns (four turns). The coil 28 detects a magnetic field in the Y-axis direction (thickness direction) passing through the loop patterns 21 to 24, and outputs a detection signal such as a voltage corresponding to a change in magnetic flux.

  On the other hand, the loop patterns 20 and 21 face each other while being insulated from each other, and constitute a capacitor 29. Thus, the coil 28 and the capacitor 29 are electrically connected in series with each other by sharing the loop pattern 21. At this time, one end side of the capacitor 29 is electrically connected to the strip conductor 14 of the transmission line portion 13 through the connecting portion 20 </ b> A, and the other end side of the capacitor 29 is electrically connected to one end side of the coil 28. The other end side of the coil 28 is electrically connected to the ground electrodes 11 and 12 through the connection portion 24B and the like.

  The magnetic field probe 1 according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  First, the tip portion of the magnetic field probe 1 is disposed in the state of being close to the surface of a measurement target (for example, a measurement target substrate). Then, the magnetic field probe 1 is moved on the surface of the measurement target. Here, when a magnetic field in the Y-axis direction is generated on the surface of the measurement object located in the vicinity of the magnetic field probe 1, this magnetic field passes through the loop patterns 20 to 24 of the detection unit 19. As a result, for example, a voltage as a detection signal is generated in the coil 28. By detecting this voltage, a magnetic field generated on the surface of the measurement target can be detected.

  However, the two loop patterns 20 and 21 located on one side in the thickness direction among the loop patterns 20 to 24 that overlap each other are insulated from each other to form a capacitor 29, and the four loop patterns 21 to 24 are The coils 28 are configured in series using via holes 25 to 27. For this reason, in the peripheral band of the resonance frequency where the coil 28 and the capacitor 29 are in series resonance, the magnetic field detection sensitivity is improved.

  Therefore, the frequency characteristics of each gain were measured for the magnetic field probe 1 according to the present embodiment and the magnetic field probe according to the comparative example in which the capacitor was omitted. The result is shown in FIG. The magnetic field probe according to the comparative example was provided with a one-turn coil.

  As shown by a broken line in FIG. 10, in the case of the comparative example, the impedance of the coil increases as the frequency increases. For this reason, the gain of the detection signal output from the magnetic field probe increases as the frequency of the detected magnetic field increases.

  In contrast, as indicated by the solid line in FIG. 10, in the case of the present embodiment, the gain of the detection signal increases as the frequency increases, as in the case of the comparative example. However, for example, in the vicinity of 1 to 5 GHz, the gain of the detection signal is improved in this embodiment compared to the comparative example. This is because the coil 28 and the capacitor 29 are in series resonance in this frequency band. Specifically, in this embodiment, since the coil 28 and the capacitor 29 are connected in series, series resonance occurs in the coil 28 and the capacitor 29 in the vicinity of 1.4 GHz that is the resonance frequency. For this reason, the gain of the detection signal can be improved in the peripheral band of the resonance frequency.

  Further, in the magnetic field probe described in Patent Document 1, since the capacitor functions as a high-pass filter in all frequency bands, for example, in a frequency band other than the resonance frequency such as a lower frequency side than the resonance frequency, the capacitor is not used. There was a tendency for the gain of the detection signal to be lower than when it was not provided.

  On the other hand, in the present embodiment, a gain comparable to that of the comparative example in which no capacitor is provided can be obtained even in a frequency band other than the resonance frequency. This is because in the magnetic field probe 1 according to the present embodiment, the loop coils 20 and 21 constituting the capacitor 29 overlap with the loop coils 21 to 24 constituting the coil 28, so that a magnetic field change at a frequency other than the resonance frequency occurs. This is because the loop coils 20 and 21 also function as part of the coil 28. That is, for example, when a magnetic flux change lower than the resonance frequency occurs, the loop coils 20 and 21 output a detection signal such as a voltage in accordance with the magnetic flux change. As a result, in the magnetic field probe 1 according to the present embodiment, for example, on the lower frequency side than the resonance frequency, the capacitor 29 does not function as a filter and functions as a part of the coil 28, and therefore a magnetic field in a frequency band other than the resonance frequency. Even in the case of detecting, a decrease in detection sensitivity can be suppressed.

  Thus, in the present embodiment, via holes 25 to 27 are provided between the remaining loop patterns 21 to 24 except for the space between two loop patterns 20 and 21 adjacent in the thickness direction among the loop patterns 20 to 24. Since it provided, the loop pattern 21-24 can be connected in series and the coil 28 of 4 turns can be comprised. For this reason, it is possible to increase the inductance and increase the detection sensitivity of the magnetic field as compared with the one-turn coil.

  In addition, the two loop patterns 20 and 21 that are not connected by the via holes 25 to 27 constitute a capacitor 29 that is opposed to each other while being insulated from each other and connected in series to the coil 28. The magnetic field can be detected with high sensitivity in the peripheral band of the resonance frequency at which resonance occurs in series. Furthermore, the loop patterns 20 and 21 constituting the capacitor 29 function as a part of the coil 28 in a frequency band other than the resonance frequency. For this reason, even when a magnetic field is detected in a frequency band other than the resonance frequency, a decrease in detection sensitivity can be suppressed.

  Since all the loop patterns 20 to 24 are formed in substantially the same winding shape, the inductance of the coil 28 can be increased as compared with the case where the loop patterns 20 to 24 have different winding shapes. In addition, since the loop patterns 20 and 21 constituting the capacitor 29 can be superimposed in the thickness direction on the loop patterns 21 to 24 constituting the coil 28, even when a magnetic field is detected in a frequency band other than the resonance frequency. The loop patterns 20 and 21 forming the capacitor 29 can function as a part of the coil 28, and a decrease in detection sensitivity can be suppressed.

  Further, the two loop patterns 20 and 21 constituting the capacitor 29 are arranged on either one of both end sides in the thickness direction of all the loop patterns 20 to 24. Therefore, the remaining loop patterns 21 to 24 arranged on the other side in the thickness direction can be connected using the via holes 25 to 27, and the capacitor 29 and the coil 28 are arranged adjacent to each other in the thickness direction. be able to.

  In the embodiment, the resonance frequency of the coil 28 and the capacitor 29 can be adjusted by increasing or decreasing the area where the loop pattern 20 and the loop pattern 21 overlap each other. Further, the resonance frequency of the coil 28 and the capacitor 29 can also be adjusted by adding or decreasing the loop patterns 21 to 24 of the coil 28.

  In the embodiment, the capacitor 29 is configured by insulating the loop patterns 20 and 21 located at one end in the thickness direction among all the loop patterns 20 to 24. However, the present invention is not limited to this. For example, as in the case of the magnetic field probe 31 according to the first modification shown in FIG. 11, the capacitors 32 are insulated by insulating between the loop patterns 21 and 22 arranged at intermediate positions in the thickness direction. May be configured.

  In this case, the connection portion 33 is provided on the other end side of the loop pattern 20, the connection portion 34 is provided on one end side of the loop pattern 21, and the via hole 35 is provided at a position corresponding to the connection portions 33 and 34. As a result, the loop patterns 20 and 21 are connected in series using the via hole 35 to constitute one coil 36. The loop patterns 22 to 24 are connected in series using via holes 26 and 27 to constitute the other coil 37. Accordingly, the capacitor 32 is connected in series between the coils 36 and 37.

  In the above-described embodiment, the case where one capacitor 29 is connected in series to the coil 28 has been described as an example, but two or more capacitors may be connected in series to the coil. In this case, the constituent positions of the capacitors may be arranged between any of the loop patterns arranged in the thickness direction. In addition, the plurality of capacitors may be disposed adjacent to each other in the thickness direction, for example, may be disposed apart from each other in the thickness direction, or may be disposed on both ends in the thickness direction.

Further, in the embodiments, all of the loop pattern 20 to 24 is also the as that having a same width dimension W0, may have a different width dimension part of the loop pattern.

  Moreover, in the said embodiment, although the loop patterns 20-24 were formed in the substantially square shape, you may form other polygonal shapes, such as a triangle and a pentagon, for example, and you may form in a circle, a semicircle, an ellipse etc. Moreover, in the said embodiment, although the loop patterns 21-24 were connected in series and the coil 28 of about 4 turns was formed, the coil of 2 turns or 3 turns may be sufficient and the coil of 5 turns or more is formed. May be.

  Furthermore, in the said embodiment, it was set as the structure which forms the magnetic field probe 1 using the 3 or more loop patterns 20-24. However, the present invention is not limited to this, and the magnetic field probe 41 may be formed using the two loop patterns 42 and 43 as in the second modification shown in FIG.

  In this case, the loop pattern 42 is formed, for example, in substantially the same manner as the loop pattern 20 according to the first embodiment, and the connection portion 42 </ b> A provided at one end thereof is connected to the strip conductor 14 through the via hole 44. On the other hand, the loop pattern 43 is formed, for example, in substantially the same manner as the loop pattern 21 according to the first embodiment, but the connecting portion 43A provided on the other end side is connected to the ground electrode (not shown) through the via hole. It is connected. Each of the loop patterns 42 and 43 constitutes a substantially one-turn coil 45 and constitutes a capacitor 46 that is opposed to each other while being insulated from each other.

1, 31, 41 Magnetic field probe 4 Multilayer substrate (substrate)
13 Transmission line section 19 Detection section 20-24, 42, 43 Loop pattern 25-27, 35 Via hole 28, 36, 37, 45 Coil 29, 32, 46 Capacitor

Claims (2)

A multilayer substrate in which a plurality of insulating layers are laminated in the thickness direction, and two or more loop patterns provided in different positions in the thickness direction across the insulating layer among the multilayer substrates and having a winding shape;
Two loop patterns adjacent to each other in the thickness direction among the two or more loop patterns constitute capacitors that are opposed to each other while being disconnected and insulated from each other ,
Each of the two or more loop patterns is a magnetic field probe formed in substantially the same winding shape .   The magnetic field according to claim 1, wherein a via hole is provided between the remaining loop patterns excluding the two loop patterns constituting the capacitor, and a coil is formed by connecting adjacent loop patterns in series. probe.

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