Oscillation device

Abstract

To match the resistances of pieces of wiring connecting a pad and a plurality of antennas among the antennas in an oscillation device.SOLUTION: An oscillation device of the present disclosure has: a substrate; a plurality of negative resistance elements that are electrically connected with the substrate; a plurality of antennas that are electrically connected one by one with the plurality of negative resistance elements and transmit or receive electromagnetic waves; a pad that is electrically connected with a power supply source for supplying power to the plurality of antennas; and a conductor that electrically connects the pad and the plurality of antennas with each other. The conductor comprises wiring common to the plurality of antennas, and individual pieces of wiring from the common wiring to the respective antennas of the plurality of antennas. In order to reduce a difference in wiring resistance occurring based on the distances between the pad and the antennas connected to the respective pieces of wiring of the individual pieces of wiring, the respective pieces of wiring are different from each other in at least one of the cross-sectional area, resistivity, and length according to the positions of the antennas on the substrate.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This disclosure relates to an oscillator that emits electromagnetic waves in the terahertz frequency band. [Background technology]

[0002] Electromagnetic waves with a frequency band of 30 GHz to 300 THz are called terahertz waves. Within the terahertz frequency band, many organic molecules, such as those found in biomaterials, pharmaceuticals, and electronic materials, exhibit absorption peaks originating from their structure and state. Furthermore, terahertz waves have high penetration properties through materials such as paper, ceramics, resins, and fabrics. In recent years, research and development of imaging and sensing technologies utilizing these characteristics of terahertz waves has been ongoing.

[0003] As such terahertz wave oscillators, structures integrating negative resistance elements such as resonant tunneling diodes (RTDs) and Gunn diodes, which have electromagnetic wave gain in the terahertz region, with a resonator are well known. In particular, structures integrating an RTD and an antenna are expected to be oscillators that operate at room temperature in the frequency range near 1 THz.

[0004] However, generally, the output of the oscillator tends to decrease as the oscillation frequency increases. Therefore, arranging structures that integrate negative resistance elements and resonators on the same substrate to form an array is used as one effective means to increase the output. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2015-180049 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Patent Document 1 anticipates increasing output power by connecting antennas with microstrip lines to achieve phase synchronization. However, because the length of the wiring electrically connecting the feed point (hereinafter referred to as pad) to each antenna in the array does not necessarily match between antennas, the resistance value of the wiring differs between antennas, causing a difference in drive voltage between antennas. Furthermore, it is known that the oscillation frequency changes when the drive voltage changes within the negative resistance region. Therefore, a problem arises in that the output power is not sufficiently increased when the electromagnetic waves of each antenna in the array are combined due to the difference in oscillation frequency between antennas.

[0007] Therefore, the present disclosure aims to provide a technique for matching the resistance value of the wiring connecting the power supply pad and the antenna in an oscillator element across multiple antennas. [Means for solving the problem]

[0008] To achieve the above objective, the oscillator element relating to this disclosure is circuit board and Multiple negative resistance elements electrically connected to the substrate, Multiple antennas for transmitting or receiving electromagnetic waves are electrically connected one-to-one with each of the multiple negative resistance elements, A power supply for supplying power to the aforementioned multiple antennas and a pad that is electrically connected to them, A conductor that electrically connects the pad and the plurality of antennas It has, The conductor has a common wiring to the plurality of antennas, and a common wiring to the plurality of antennas. It consists of individual wiring to each antenna of the Tenor, To reduce the difference in wiring resistance that arises based on the distance between the antenna connected to each of the individual wires and the pad, each of the wires has at least one of the following characteristics: cross-sectional area, resistivity, and length, depending on the position of the antenna connected to each of the wires on the substrate. Includes an oscillator characterized by the following features. [Effects of the Invention]

[0009] According to this disclosure, a sufficient output can be obtained when the electromagnetic waves of antennas are combined in an oscillator. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic top view showing an example of an oscillator element according to this embodiment. [Figure 2] Cross-sectional view along line A-A' in Figure 1 [Figure 3] Cross-sectional view along line B-B' in Figure 1 [Figure 4] A schematic top view showing an example of an oscillator element according to Example 1. [Figure 5] A schematic top view showing an example of an oscillator element according to Example 2. [Figure 6] A schematic top view showing an example of an oscillator element according to Example 3. [Figure 7] A schematic top view showing an example of an oscillator element according to Example 4. [Figure 8] A schematic top view showing an example of an oscillator element according to Example 5. [Figure 9] Cross-sectional view along the line C-C' in Figure 8. [Figure 10] A schematic top view showing an example of an oscillator element according to Example 6. [Figure 11] Figure 11A is a cross-sectional view taken along the line D-D' in Figure 10, and Figure 11B is a cross-sectional view taken along the line B-B' in Figure 10. [Figure 12] A schematic top view showing an example of an oscillator element according to Example 7. [Figure 13] Figure 13A is a schematic diagram showing the structure of the RTD oscillator according to this embodiment, Figure 13B is a graph conceptually showing the energy barrier and electron resonant tunneling effect of the RTD when voltage is applied, and Figure 13C is a graph showing an example of the current-voltage characteristics of the RTD. [Figure 14] Equivalent circuits of each wire from the pad to the antenna in Figure 1 [Figure 15]A schematic diagram showing the definition of resistor dimensions. [Figure 16] Figures 16A to 16L show the process for creating the oscillator element according to this embodiment. [Figure 17] Figure 17 is a schematic top view showing an example of an oscillator element according to Example 8. [Figure 18] Figure 18 shows a portion of the oscillator element in Figure 17. [Figure 19] Figure 19 is a perspective view showing the manufacturing process of the oscillator element according to Example 8. [Figure 20] Figure 20 is a cross-sectional view taken along the line F-F' in Figure 18. [Modes for carrying out the invention]

[0011] Embodiments of this disclosure will be described below with reference to the drawings. However, this disclosure is not limited to the embodiments described below, and may be modified as appropriate without departing from its essence. Furthermore, in the drawings described below, components having the same function will be denoted by the same reference numerals, and their descriptions may be omitted or simplified.

[0012] The oscillator element according to this embodiment will be described with reference to Figures 1 to 3. Figure 1 is a top view of the oscillator element, Figure 2 is a cross-sectional view taken along the line A-A' in Figure 1, and Figure 3 is a cross-sectional view taken along the line B-B' in Figure 1. In the following descriptions of each embodiment, unless otherwise specified, the cross-sectional structure of the oscillator element will be the same as that shown in Figures 2 and 3.

[0013] The oscillator element 100 of this embodiment has an antenna structure for transmitting or receiving electromagnetic waves. As shown in Figures 2 and 3, the oscillator element 100 includes a substrate 102, a ground metal (GND) 103, a negative resistance element 101a, a first insulator 107, and a second insulator 108 The oscillator element 100 also has antennas 104a to 104c, bias lines 105 and 106a to 106c for transmitting or receiving electromagnetic waves. In this embodiment, multiple antennas 104a to 104c are arranged in an array on the substrate 102. Antennas 104a to 104c are electrically connected to the pad 110 via bias line 105 (wiring common to the antennas) and bias lines 106a to 106c (individual wiring for each antenna). Furthermore, the pad 110 is connected to the power supply 112 via wiring 111 including wire bonding.

[0014] The pad 110 is for making an electrical connection between the external circuit of the oscillator element 100 and the antenna, and for example, for supplying a predetermined voltage from the outside. The pad 110 is made of a conductor. Hereinafter, the pad is for electrically connecting to an external power supply for supplying power to the antenna. More specifically, the pad is for receiving a predetermined voltage from the outside, and can also be for supplying a predetermined voltage to the outside. In this embodiment, the predetermined voltage can be the ground voltage, the power supply voltage, the voltage from the voltage bias circuit, etc.

[0015] In the oscillator element 100, an InP substrate is used for the substrate 102, and multiple negative resistance elements 101a to 101c are arranged on the substrate 102 as a semiconductor multilayer film that generates terahertz waves, thereby obtaining gain in the frequency domain of terahertz waves. For example, resonant tunneling diodes (RTDs) or Gunn diodes can be used for the negative resistance elements 101a to 101c. In the following description, as an example, the negative resistance elements 101a to 101c will be assumed to be composed of RTDs.

[0016] The substrate 102 is connected to the ground metal 103, which is at ground potential, by ohmic contact. In the oscillator element 100, the cathode side is connected from the ground metal 103 to the negative resistance elements 101a to 101c via the substrate 102. The anode side is connected from the bias lines 106a to 106c to the antennas 104a to 104c, and the antennas 104a to 104c are connected to the negative resistance elements 101a to 101c. The antennas 104a to 104c are electrically connected one-to-one with the negative resistance elements 101a to 101c. By applying a bias voltage from the power supply 112 to the negative resistance elements 101a to 101c, terahertz waves can be oscillated by the negative resistance elements 101a to 101c and the antennas 104a to 104c, which act as resonators. Here, terahertz waves are electromagnetic waves that contain frequency components ranging from 30 GHz to 30 THz.

[0017] As shown in Figure 1, for antennas 104a to 104c, the distance between adjacent antennas is defined as the distance d between the ends of the antennas. It is known that there is a correlation between the antenna spacing d and the directivity of the entire antenna array. By setting the antenna spacing d to be an integer multiple of the wavelength of the oscillating electromagnetic wave or less than or equal to the wavelength, preferably less than or equal to half the wavelength, the effect of combining electromagnetic waves in the far field can be obtained. Therefore, in the following description, the antenna spacing d will be an integer multiple of the wavelength of the oscillating electromagnetic wave or less than or equal to the wavelength.

[0018] The oscillation principle and the drive voltage dependence of the oscillation frequency of the RTD oscillator in this embodiment will be explained. First, the oscillation principle will be explained using Figures 13A to 13C. Figure 13A is a diagram showing an example of the structure of an RTD used in the RTD oscillator. Figure 13B is a diagram conceptually explaining the energy barrier of the RTD and the electron resonant tunneling effect when a voltage is applied. Figure 13C is a diagram showing the current-voltage characteristics of the RTD. As shown in Figure 13A, the RTD 118 consists of a quantum well layer 117 and barrier layers 116a and 116b provided in contact with the upper and lower surfaces of it. The film thickness of the barrier layers 116a and 116b is thinner than the film thickness of the quantum well layer 117.

[0019] The collector 121 and electrode 122 are located in the upper layer of the RTD118, and the emitter 120 and ground 119 are located in the lower layer. As shown in Figure 13B, when the drive voltage is increased by the power supply 123, the electron level on the emitter 120 side eventually matches the resonance level of the quantum well layer 117, and electrons pass through the energy barrier 124 as indicated by arrow 125 due to the resonant tunneling effect. As a result, current flows on the collector 121 side. If the drive voltage is further increased, the electron level on the emitter 120 side becomes higher than the resonance level, electrons cannot pass through the barrier layers 116a and 116b, and the current decreases.

[0020] The region (voltage range) 126 shown in Figure 13C is the negative resistance region. Generally, in an LC oscillator circuit composed of a coil and a capacitor, oscillation converges due to resistance loss, whereas in an LC oscillator circuit with negative resistance, oscillation continues due to behavior that cancels out resistance loss.

[0021] Next, we will explain the drive voltage dependence of the oscillation frequency. Let C be the capacitance of the RTD oscillator element including the antenna, and L be the inductance of the antenna. A Therefore, the oscillation frequency f0 of the RTD is calculated by the following equations (1) and (2).

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[0022] Here, C A C is the capacitance of the antenna. C0 is the capacitance determined by the dielectric constant, area, and film thickness of RTD118, including emitter 120 and collector 121. RTD This is the capacitance of the RTD118 that is considered when a voltage is applied in the negative resistance region.

[0023] L A and C A This is independent of the drive voltage, and the change in C0 due to the drive voltage is CRTD is negligibly small compared to the change due to the drive voltage. Therefore, in the change of the oscillation frequency f0 of the RTD due to the change of the drive voltage, C RTD 's drive voltage dependence is dominant. C RTD is the capacitance that occurs when electrons remain between the emitter 120 and the collector 121 for the duration of the electron delay time when a voltage is applied in the negative resistance region, and is determined by the quantum mechanical tunneling time (t RTD ) and the negative differential conductance (NDC).

[0024] t RTD and NDC both have a drive voltage dependence, so C RTD depends on the drive voltage, and as a result, the oscillation frequency f0 has a drive voltage dependence. And C RTD is known to gradually increase near the voltage at which the current peaks in the negative resistance region of the RTD and decrease steeply as the voltage increases. Due to this, in the negative resistance region of the RTD, when the drive voltage changes, the oscillation frequency f0 changes steeply. In such a principle, it is important to match the wiring resistance and the drive voltage between the antennas during array formation.

[0025] s In FIG. 1, for example, let the resistance value of the wiring from the pad 110 to the antenna 104a be R a , and the resistance value of the wiring from the pad 110 to the antenna 104c be R c . Compare the resistance value R a with the resistance value R c . FIG. 14 shows the equivalent circuit of the wiring from the pad 110 to the antennas 104a and 104c. The resistance value R a is determined only by the resistance of the bias line 106a, but the resistance value R c is determined by the series resistance of the resistance of the bias line 105 and the resistance of the bias line 106c ance. In FIG. 14, let the resistance value of the bias line 106a be R ad , the resistance value of the bias line 105 be R cc , and the resistance value of the bias line 106c be R cd . Then, R a = Rad and R c =R cc +R cd This is the result.

[0026] In Figure 1, the resistivity and film thickness of bias line 105, which is a common wiring for multiple antennas, and bias lines 106a to 106c, which are individual wirings from bias line 105 to each antenna, are all equal. Also, the width w of bias lines 106a to 106c a ~w c They are equal to each other, and the bias line 106a~106c length l a ~l c These are equal to each other. In general, in the resistor 127 shown in Figure 15, the width w, thickness t, and length l of the resistor 127 are defined with respect to the direction of current flow 128. In this case, the resistance value R of the resistor 127 is expressed by the following equation (3), using resistivity ρ and cross-sectional area S=wt.

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[0027] Therefore, in Figure 14, R ad =R cd And so, R a <R c Therefore, the drive voltage differs between antenna 104a and antenna 104c. Assuming that the resistivity, cross-sectional area, and length of the common wiring are fixed values, R a and R c To make them match, R cd =R ad -R cc R cd and R adOne of the two is changed relative to the other. If the resistivity and length are fixed values, the cross-sectional area of ​​bias line 106c is made larger than the cross-sectional area of ​​bias line 106a. Here, the cross-sectional area of ​​the bias line is determined by the product of the film thickness and the width. Therefore, if the film thickness is fixed value, the width of bias line 106c is made larger than the width of bias line 106a. Also, if the width is fixed value, the film thickness of bias line 106c is made larger than the film thickness of bias line 106. Also, if the resistivity and cross-sectional area are fixed values, the length of bias line 106a is made longer than the length of bias line 106. Also, if the cross-sectional area and length are fixed values, the resistivity is effectively changed by constructing either or both of bias line 106a and bias line 106c from multiple types of materials.

[0028] In this embodiment, at least one of the parameters that determine the resistance value—resistivity ρ, cross-sectional area S, and length l—is set to a different value between at least one antenna and another in the antenna array. That is, in order to reduce the difference in wiring resistance that arises based on the distance between each individual wiring and the antenna and pad connected to it, each wiring has at least one of the cross-sectional area, resistivity, and length that differs from one another, depending on the position on the substrate of each antenna connected to each wiring.

[0029] Next, an example of the process for creating an oscillator element common to each embodiment described below will be explained with reference to Figures 16A to 16L. Figures 16A to 16F show cross-sectional views of the oscillator element 100 in each process along line A-A' in Figure 1, and Figures 16G to 16L show cross-sectional views of the oscillator element 100 in each process along line B-B' in Figure 1.

[0030] In Figures 16A and 16G, a negative resistance element 101a, as an epitaxially grown semiconductor multilayer film, is formed in a mesa shape on the substrate 102 by photolithography. In Figures 16B and 16H, a ground metal (GND) 103 is formed on the substrate 102 by photolithography. In Figures 16C and 16I, a first insulator 107 is deposited on the substrate 102, the negative resistance element 101a, and the ground metal (GND) 103, and a first contact hole is formed by photolithography. In Figures 16D and 16J, bias lines 105 (common wiring between antennas) and bias lines 106a (individual wiring for each antenna) are shown. The wiring (separate wiring) and pad 110 are formed by photolithography. In Figures 16E and 16K, the second insulator 108 is deposited and the second contact hole is formed by photolithography. In Figures 16F and 16L, the antenna 104a is formed by photolithography. Antennas 104b and 104c are formed in the same way as antenna 104a by the above process.

[0031] The above describes the process for creating the oscillator element, which is common to each of the following embodiments. Additional steps in each embodiment will be described in detail in the description of each embodiment. The embodiments will now be described.

[0032] (Example 1) The oscillator element according to Embodiment 1 will be described with reference to Figure 4. Figure 4 is a schematic top view showing an example of the oscillator element according to Embodiment 1. In the oscillator element according to this embodiment, the antennas are arranged in a 1x3 array on the second insulator 108, and each antenna is configured to be fed power from one direction. As shown in the figure, the wiring width w of the bias lines 106a to 106c a ~w c By making each of them have a different width, the wiring resistance from pad 110 to antennas 104a to 104c is made the same. Furthermore, the resistivity and film thickness of bias line 105, which is a common wiring for each antenna, and bias lines 106a to 106c, which are individual wirings from bias line 105 to each antenna, are assumed to be the same.

[0033] In Figure 4, the wiring width and wiring length of bias line 105 are denoted as W and L, respectively, and the wiring length of bias lines 106a to 106c is denoted as l. In this embodiment, the width w of bias line 106a is denoted as w. a Fix it in place, and adjust the width of the bias line 106b so that the wiring resistance from pad 110 to antennas 104a to 104c matches. b and the width of the bias line 106c w c This changes the cross-sectional area of ​​the bias lines 106a to 106c, so that it becomes smaller the closer the position of the antennas 104a to 104c, which are connected to the bias lines 106a to 106c, is to the pad 110 on the substrate 102. In Figure 4, antennas 104b and 104a are positioned closer to the pad 110 than antenna 104c, and antenna 104a is positioned closer to the pad 110 than antenna 104b. Therefore, the width w of the bias lines 106a to 106c a , w b、 w c lol a <w b <w c It will be set to be as follows.

[0034] If the wiring resistances from pad 110 to antennas 104a to 104c are the same, then with respect to antenna 104b, w b and lol a The relationship is given by equation (4) below, and w c and lol a The relationship is given by equation (5) below.

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[0035] In this example, L=500μm, l=200μm, W=600μm, w a If we set it to =80μm, then w b =122μm, w c The result is calculated to be 240 μm.

[0036] (Example 2) Next, an example of an oscillator element according to Example 2 will be described with reference to Figure 5. Figure 5 is a schematic top view showing an example of an oscillator element according to Example 2.

[0037] In this embodiment, similar to Embodiment 1, the antennas are arranged in a 1x3 array on the second insulator 108. In this embodiment, each antenna on the second insulator 108 is configured to be supplied with power from two directions, above and below the antenna. As shown in the figure, the wiring width w of the bias lines 106a1 to 106c1, which are the individual wirings for each antenna, is shown. a1 ~w c1 Each of these will have a different width. Similarly, the wiring width w of the bias lines 106a2~106c2, which will be the individual wiring for each antenna, will be different. a2 ~w c2 Each of these is given a different width. This ensures that the wiring resistance from pad 110 to antennas 104a to 104c is the same. In addition, the resistivity and film thickness of bias line 105, which is a common wiring for each antenna, and bias lines 106a to 106c, which are individual wirings from bias line 105 to each antenna, are all the same.

[0038] In Figure 5, the wiring width and wiring length of bias lines 105a and 105b are denoted as W and L, respectively, and the wiring length of bias lines 106a1 to 106c2 is denoted as l. In this embodiment, each antenna is supplied with power from two directions, above and below the antenna, on the second insulator 108. Due to the symmetry of the power supply direction to the antenna, w a1 =w a2 , w b1 =w b2 , w c1 =w c2 This is the result. Also, in this embodiment, w a1 =w a2 Secure it, and make sure the wiring resistances from pads 110 to 104a to 104c match each other, w b1 (=w b2 ) and w c1 (=w c2) is changed. More specifically, similar to Example 1, the cross-sectional area of ​​bias lines 106a1 to 106c1 is set to decrease as the position of antennas 104a to 104c connected to bias lines 106a1 to 106c1 on the substrate 102 approaches the pad 110. Also, the cross-sectional area of ​​bias lines 106a2 to 106c2 is set to decrease as the position of antennas 104a to 104c connected to bias lines 106a2 to 106c2 on the substrate 102 approaches the pad 110.

[0039] If the wiring resistances from pad 110 to 104a~104c are the same, then with respect to antenna 104b, w b1 and lol a1 The relationship is given by equation (6) below, and w c1 and lol a1 The relationship is given by equation (7) below.

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[0040] In this example, L=500μm, l=200μm, W=600μm, w a1 =w a2 If we set it to =80μm, then w b1 =w b2 =122μm, w c1 =w c2 The result is calculated to be 240 μm.

[0041] Therefore, with the oscillator element according to Embodiment 2, even if the number of feeding directions to the antennas increases compared to Embodiment 1, it is possible to match the wiring resistance for each antenna. In this embodiment, the feeding direction to each antenna is vertical, but the feeding direction is not limited to vertical.

[0042] (Example 3) Next, an example of the oscillation element according to Example 3 will be described with reference to FIG. 6. FIG. 6 is a top view schematically showing an example of the oscillation element according to Example 3.

[0043] In this embodiment, as in Examples 1 and 2, the antennas are arranged in a 1×3 array in the second insulator 108. In this embodiment, a plurality of pads are arranged on the substrate 102. Further, on the second insulator 108, the bias line 105 is fed from the left and right two directions of the bias line 105 via the pads 110a and 110b. Also, the wiring widths w a ~w c of the bias lines 106a to 106c are set to widths corresponding to the wiring lengths from the pad 110a or the pad 110b to the antennas 1104a to 104c. Thereby, the wiring resistances from the pads 110a and 110b to the antennas 104a to 104c are made to match respectively. Here, due to the symmetry of the feeding direction with respect to the bias line 105, w a =w c is satisfied. Also, it is assumed that the resistivity and the film thickness of the bias line 105, which is the common wiring for each antenna, and the bias lines 106a to 106c, which are the individual wirings from the bias line 105 to each antenna, are the same.

[0044] In FIG. 6, let the wiring width and the wiring length of the bias line 105 be W and L respectively, and the wiring length of the bias lines 106a to 106c be l. In this embodiment, the width w a (=w c ) is fixed, and w b is changed so that the wiring resistances from the pads 110a and 110b to the antennas 104a to 104c match each other.

[0045] Let the combined wiring resistance from the pads 110a and 110b to the antenna 104a be R a , and the combined wiring resistance from the pads 110a and 110b to the antenna 104b be R b . Then, when the resistivity of the bias line 105 and the bias lines 106a to 106c is ρ and the film thickness is t, the following equations (8) and (9) hold.

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[0046] In this embodiment, as an example, when L = 500 μm, l = 200 μm, W = 600 μm, and w a = w c = 60 μm, when R a = R b and w b = 62 μm is obtained.

[0047] In Embodiment 3, in order to reduce the difference in the combined wiring resistance from each pad to each antenna, for each wiring, at least one of the cross-sectional area, resistivity, and length is different from each other according to the position on the substrate of the antenna connected to each wiring. Therefore, according to the oscillation element according to Embodiment 3, even if the number of pads for feeding power to the bias line 105 is changed as shown in FIG. 6, it is possible to make the wiring resistance for each antenna coincide.

[0048] (Embodiment 4) Next, an example of the oscillation element according to Embodiment 4 will be described while referring to FIG. 7. FIG. 7 is a top view schematically showing an example of the oscillation element according to Embodiment 4.

[0049] In this embodiment, similar to Embodiments 1 to 3, the antennas are arranged in a 1×3 array in the second insulator 108. In this embodiment, in the second insulator 108, the antennas 104a to 104c are configured to be fed power from one direction. Also, the wiring lengths l a ~l cEach of these is given a different wiring length. This ensures that the wiring resistance from pad 110 to antennas 104a to 104c is the same. Furthermore, the resistivity and film thickness of the bias line 105, which is a common wiring for all antennas, and the bias lines 106a to 106c, which are individual wirings from bias line 105 to each antenna, are all assumed to be the same.

[0050] In Figure 7, the wiring width and wiring length of bias line 105 are denoted as W and L, respectively, and the wiring width of bias lines 106a to 106c is denoted as w. a =w b =w c In this study, l c Fix it in place, and set the wiring resistance from pad 110 to antennas 104a to 104c to match each other. a and l b This changes the value. If the wiring resistances from pad 110 to antennas 104a to 104c are the same, then with respect to antenna 104a, l a and l c The relationship is given by the following equation (10), l b and l c The relationship is given by equation (11) below.

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[0051] In this example, L=500μm, W=600μm, w a =w b= w c =80μm, l c If we set it to =200μm, then l a =333μm, l b The result is calculated to be 267 μm.

[0052] Therefore, with the oscillator element according to Example 4, it is possible to match the wiring resistance for each antenna even if the wiring width and wiring length of the wiring connected to the antenna are changed, compared to Example 1.

[0053] (Example 5) Next, an example of an oscillator element according to Example 5 will be described with reference to Figures 8 and 9. Figure 8 is a schematic top view showing an example of an oscillator element according to Example 5. Figure 9 is a cross-sectional view taken along the line C-C' in Figure 8.

[0054] In this embodiment, similar to embodiments 1 to 4, the antennas are arranged in a 1x3 array on the second insulator 108. In this embodiment, the second insulator 108 is configured to supply power to the antennas 104a to 104c from one direction. Also, the film thickness t of the bias lines 106a to 106c a ~t c Each of these is given a different film thickness. This makes the wiring resistance from pad 110 to antennas 104a to 104c the same. In addition, the resistivity of bias line 105, which is a common wiring for each antenna, and bias lines 106a to 106c, which are individual wirings from bias line 105 to each antenna, are assumed to be the same.

[0055] In Figure 8, the wiring width and wiring length of the bias line 105 are denoted as W and L, respectively. Wiring width of IAS line 106a~106c w a =w b =w c Let T be the thickness of the bias line 105. In this embodiment, the thickness t of the bias line 106a is a Fix it in place and ensure that the wiring resistance from pad 110 to antennas 104a to 104c matches the thickness of the bias line 106b. b and bias line 106c film thickness t c This was changed. In this embodiment, the cross-sectional area of ​​the bias lines 106a to 106c is made smaller for antennas 104a to 104c that are positioned closer to the pad 110, thereby matching the wiring resistance from the pad 110 to antennas 104a to 104c. When the wiring resistance from the pad 110 to antennas 104a to 104c matches, with respect to antenna 104b, t b and ta The relationship is given by the following equation (12), and with respect to antenna 104c, t c and t a The relationship is given by equation (13) below.

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[0056] In this example, L=500μm, l=200μm, W=600μm, w a =w b= w c =80μm, t a If we set =T=500nm, then t b =750nm, t c It is calculated to be = 1500nm.

[0057] Therefore, with the oscillator element according to Example 5, it is possible to match the wiring resistance between antennas even if the thickness of the wiring connected to the antenna is changed, compared to Example 1.

[0058] (Example 6) Next, an example of an oscillator according to Embodiment 6 will be described with reference to Figures 10, 11A, and 11B. Figure 10 is a schematic top view showing an example of an oscillator according to Embodiment 6. Figure 11A is a cross-sectional view taken along the line D-D' in Figure 10, and Figure 11B is a cross-sectional view taken along the line B-B' in Figure 10.

[0059] In this embodiment, similar to embodiments 1 to 5, the antennas are arranged in a 1x3 array on the second insulator 108. In this embodiment, the second insulator 108 is configured to supply power to antennas 104a to 104c from one direction. Furthermore, the bias line from bias line 105 to antennas 104a and 104b is constructed using multiple materials.

[0060] Specifically, as shown in Figure 11A, bias line 106a is composed of bias lines 106a1 and 106a2, and bias line 113a connecting to bias lines 106a and 106a2. Also, as shown in Figure 11B, bias line 106b is composed of bias lines 106b1 and 106b2, and bias line 113b connecting to bias lines 106b1 and 106b2. Furthermore, the materials constituting bias lines 106a1 and 106a2 (first material) and bias line 113a (second material) are different. Similarly, the materials constituting bias lines 106b1 and 106b2 (first material) and bias line 113b (second material) are different.The lengths of bias lines 106a to 106c and 113a to 113c are set according to the positions of antennas 104a to 104c relative to pad 110. This allows the antenna to be connected to pad 110. The wiring resistances from 104a to 104c were matched.

[0061] As shown in Figures 10, 11A, and 11B, in a top view of the second insulator 108 (substrate 102, antennas 104a~104c), the lengths of bias lines 106a1, 106a2, and 113a from bias line 105 to antenna 104a are set to l. Similarly, the lengths of bias lines 106b1, 106b2, and 113b from bias line 105 to antenna 104b are also set to l. Furthermore, the lengths of bias lines 113a and 113b are set to l. a ',l b Let's assume that.

[0062] Furthermore, a third insulator 109 is added to the substrate 102 as a component of the oscillator element, and as shown in Figure 11A, bias lines 106a1, 106a2 and bias line 113a are electrically connected via contact holes provided in the third insulator 109. Similarly, as shown in Figure 11B, bias lines 106b1, 106b2 and bias line 113b are electrically connected via contact holes provided in the third insulator 109. In this embodiment, bias lines 106a1 and 106a2 are formed on the substrate 102 as first wirings of the first layer using the first material, and bias line 113a is formed as a second wiring of the second layer using the second material. Similarly, bias lines 106b1, 106b2 and bias line 113b are formed in the same manner.

[0063] Furthermore, the film thickness of bias line 105, which is a common wiring for each antenna, and bias lines 106a1~106c and 113a~113c, which are individual wirings from bias line 105 to each antenna, are all the same.

[0064] In Figure 10, the wiring width and length of bias line 105 are denoted as W and L, respectively, and the wiring width of bias lines 106a1 to 106c is denoted as w. a =w b =w c The wiring width of bias lines 106a1 and 106a2 is w a The wiring width for bias lines 106b1 and 106b2 is w b The resistivity of bias lines 106a1 to 106c is ρ1, and the resistivity of bias lines 113a to 113c is ρ2. The wiring resistance from pad 110 to antennas 104a to 104c is R. a , R b , R c Let R be the case. a =R c In this case, the following equation (14) holds, R b =R c In this case, the following equation (15) holds true.

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[0065] In this embodiment, as an example, ρ1 = 4.1 × 10 -8 Ωm, ρ² = 1.15 × 10 -7 Ωm, L=500μm, W=600μm, w a =w b =w c If l = 130 μm and l = 200 μm, then l a '=120μm, l b '=60μm is calculated.

[0066] Therefore, with the oscillator element according to Example 6, it is possible to match the wiring resistance between antennas even when the bias line is constructed using multiple types of materials, compared to Example 1. Furthermore, as with the oscillator element according to Example 6, the bias line can be constructed with multiple layers. This is expected to increase the degree of freedom in arranging components on the circuit board.

[0067] (Example 7) Next, an example of an oscillator according to Example 7 will be described with reference to Figure 12. Figure 12 is a schematic top view showing an example of an oscillator according to Example 7.

[0068] In Examples 1 to 6, the antennas are arranged in a one-dimensional array on the second insulator 108, but in this embodiment, the antennas are arranged in a 3x3 two-dimensional array on the second insulator 108. Furthermore, the second insulator 108 is configured to supply power to the antennas 104a to 104i from one direction (from the bottom of the paper in the example shown in the figure).

[0069] In this embodiment, in the second insulator 108, the bias line, which is the wiring from the bias line 105 to each antenna, is divided into segments 114a to 114i and segments 115a to 115i that extend in the vertical direction. Segments 115a to 115i extend horizontally from segments 114a to 114i and connect to antennas 104a to 104i. Here, the vertical direction, which is the direction in which segments 114a to 114i extend, is the direction in which antennas 104d and 104g are positioned relative to antenna 104a in Figure 12 (the up-down direction on the paper in the example shown). The horizontal direction is the direction in which antennas 104b and 104c are positioned relative to antenna 104a in Figure 12 (the left-right direction on the paper in the example shown).

[0070] The wiring widths of segments 114a to 114i increase segment by segment as they move away from pad 110. Similarly, the wiring widths of segments 115a to 115i also increase segment by segment as they move away from pad 110. As shown in the figure, let the wiring widths of segments 114a to 114i be Wa to Wi respectively. At this time, in the vertical direction, in the relationship of Wa, Wd, Wg, Wa < Wd < Wg; in the relationship of Wb, We, Wh, Wb < We < Wh; in the relationship of Wc, Wf, Wi, Wc < Wf < Wi. Also, in the horizontal direction, in the relationship of Wa, Wb, Wc, Wa < Wb < Wc; in the relationship of Wd, We, Wf, Wd < We < Wf; in the relationship of Wg, Wh, Wi, Wg < Wh < Wi. Similarly, as shown in the figure, let the wiring widths of segments 115a to 115i be W’a to W’i respectively. At this time, in the vertical direction, in the relationship of W’a, W’d, W’g, W’a < W’d < W’g; in the relationship of W’b, W’e, W’h, W’b < W’e < W’h; in the relationship of W’c, W’f, W’i, W’c < W’f < W’i. Also, in the horizontal direction, in the relationship of W’a, W’b, W’c, W’a < W’b < W’c; in the relationship of W’d, W’e, W’f, W’d < W’e < W’f; in the relationship of W’g, W’h, W’i, W’g < W’h < W’i. Note that it is assumed that the resistivity and film thickness of bias line 105, which is the common wiring for each antenna, and segments 114a to 114i and segments 115a to 115i of the bias line, which are the individual wirings from bias line 105 to each antenna, are the same.

[0071] In this embodiment, unlike embodiments 1 to 6, the bias line, which is the individual wiring from the bias line 105 to each antenna, is divided into two regions: segments 114a to 114i and segments 115a to 115i. Here, segments 114a to 114i become the first segment, which is the wiring for at least two of the multiple antennas. Segments 115a to 115i become the second segment, which electrically connects the first segment to each of the at least two antennas. Considering the case where the antennas are arranged in a two-dimensional array as shown in Figure 12, we focus on antennas 104a, 104b, and 104c. In Figure 12, the resistance value of the wiring from pad 110 to segments 115a, 115b, and 115c of each antenna is R a , R b , R c Let R be the case. a =R b =R c The wiring width w of segments 114a, 114b, and 114c is such that a , w b , w c Each of these will be determined.

[0072] Furthermore, let us focus on antennas 104a and 104d as an example. In Figure 12, the resistance value of the wiring from pad 110 to segment 115d of antenna 104d is R d Let's assume that the resistance value of segment 114a is R ad The resistance value of segment 114d is R dd Therefore, since the wiring from pad 110 to segment 115a is common, R a <R d This is how it works. In this embodiment, the width w' of segments 115a and 115d is set so that the resistance value of the wiring from pad 110 to antenna 104a matches the resistance value of the wiring from bias line 105 to antenna 104d. a and w' dThe width w' of segment 115d and segment 115g is determined so that the resistance values ​​of the wiring from pad 110 to each antenna are the same between antenna 104d and antenna 104g. d and w' g The width of each segment w' is determined so that the resistance values ​​of the wiring from pad 110 to each antenna match between antennas 104b, 104e, and 104h, and between antennas 104c, 104f, and 104i. e , w' h , w' f , w' i This is determined. As a result, in this embodiment, it is possible to adjust the width of segments 114a to 114i and segments 115a to 115i of the bias line to match the wiring resistance from pad 110 to each antenna 104a to 104i.

[0073] Here, the resistance value of the wiring from pad 110 to antenna 104x (x=a~i) is R x Let (x=a~i). Also, let w be the wiring width of segment 114x (x=a~i). x (x=a~i), the wiring width of segment 115x(x=a~i) is w' x (x=a~i), let W be the wiring width of bias line 105. The wiring lengths of segments 114a~114i are all the same, with l=400μm. Similarly, the wiring lengths of segments 115a~115i are all the same, with l'=130μm. Note that the wiring length l' is expressed as l'=l1+l2, given by l1 and l2, as shown in Figure 12.

[0074] In Figure 12, the wiring widths of segments 114a, 115a, 115b, 115c, and bias line 105 are respectively w a =100μm, w' a =20μm, w' b =22μm, w' c Let =24μm and W=600μm.

[0075] As shown in Figure 12, let L1 be the distance from the contact point on the pad 110 side between bias line 105 and segment 114a to the contact point on the pad 110 side between bias line 105 and segment 114b. Also, let L2 be the distance from the contact point on the pad 110 side between bias line 105 and segment 114b to the contact point on the pad 110 side between bias line 105 and segment 114c. Furthermore, the distance x between each of segments 114a to 114i and each antenna is equal for all antennas, and x = 10 μm. In this embodiment, the side length d of each antenna in the square is d. A The antenna spacing d is kept constant for each antenna. Therefore, L1 is d A ,d,w a , w b Between L1 and d A +d+w a ―w b The relationship holds, and L2 is d A d, w b , w c Between L2 and d A +d+w b ―w c The following conditions must be met. Also, in this embodiment, d A Let = 170 μm and d = 300 μm.

[0076] First, equation (16) holds between antenna 104a and antenna 104b, and equation (17) holds between antenna 104b and 104c, so that the wiring resistance is the same between antennas 104a, 104b, and 104c. From equations (16) and (17), w b = 105 μm, w c This equals 113 μm.

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[0077] Next, these w a , w b , w cBased on the value, the width of each of the vertically extending segments 114d, 114e, 114f, 114g, 114h, and 114i is set so that they become wider the further they are from the pad 110. Here, w d =150μm, w e =170μm, w f =190μm, w g =200μm, w h =220μm, w i Set to =240μm. Then, based on the width values ​​of these segments, determine the wiring widths of segments 115d, 115e, 115f, 115g, 115h, and 115i so that the wiring resistance of adjacent antennas in the vertical direction matches. For example, equation (18) holds true for the relationship between antennas 104a and 104d.

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[0078] Therefore, according to the oscillator element of Example 7, unlike Example 1, it is possible to match the wiring resistance between antennas even when the arrangement of antennas on the substrate is a two-dimensional array.

[0079] In the above description of Example 7, the widths, i.e., cross-sectional areas, of segments 114a to 114i and segments 115a to 115i are configured to differ from each other depending on the positions of the antennas 104a to 104i relative to the pad 110. Alternatively, or in addition to this, at least one of the resistivity and length of segments 114a to 114i and segments 115a to 115i may be configured to differ from each other depending on the positions of the antennas 104a to 104i relative to the pad 110.

[0080] (Example 8) Next, an example of an oscillator element according to Example 8 will be described with reference to Figures 17 to 20. Figure 17 is a schematic top view showing an example of an oscillator element according to Example 8, Figure 18 is a top view cropped from a part of Figure 17, and Figure 19 shows a perspective view of the manufacturing process, which is particularly characteristic of this example, in the fabrication process shown in Figure 16. Figure 20 shows a cross-sectional view taken along the line F-F' in Figure 18.

[0081] In this embodiment, as shown in Figure 17, the antennas are arranged in a 6x6 two-dimensional array on the second insulator 108. Furthermore, each antenna on the second insulator 108 is configured to be supplied with power from four directions. That is, similar to Embodiment 7, the bias lines, which are individual wirings to each antenna, are divided into two regions: segments 114a to 114x and segments 115a to 115r.

[0082] In this embodiment, due to the symmetry of the antenna arrangement shown in Figure 17, the wiring resistance is adjusted using only the 3x3 array shown in Figure 18. In Figure 17, only the pads 110a to 110d, wiring including wire bonding 111a to 111d, power supplies 112a to 112d, negative resistance elements 101a to 101i, and antennas 104a to 104i are shown. In Figure 17, the X-X' plane... Furthermore, with the Y-Y' plane as the plane of symmetry, the regions of the four 3x3 arrays are arranged symmetrically to one another, and Figure 18 shows a top view of the 3x3 array including pad 110a that has been cut out.

[0083] In this embodiment, the common bias line consists of segments 105a to 105f, while the bias lines for each antenna are divided into segments 114a to 114x and segments 115a to 115r. As shown in Figure 19, both the common bias line and the bias lines for each antenna are formed in two layers. All segments constituting the first wiring in the first layer and all segments constituting the second wiring in the second layer have the same wiring width and length, and the same reference numerals are assigned to the segments constituting the first wiring and the segments constituting the second wiring. The first wiring (indicated as 191 in the figure) is formed in the steps shown in Figures 16D and 16J. The second wiring (indicated as 193 in the figure) is formed in the steps shown in Figures 16F and 16L. The first and second wirings are connected by a second contact hole (indicated as 192 in the figure) formed in the steps shown in Figures 16E and 16K.

[0084] Segments 114a to 114x are arranged in a grid pattern. Of these, segments 114a to 114l extend horizontally above and below each antenna, while segments 114m to 114x extend vertically to the left and right of each antenna. Segment 115z (z=a to r) is further divided into segments 129z (z=a to r) and 130z (z=a to r). Segments 115a to 115r extend horizontally from segments 114m to 114x, and segments 130a to 130r connect to antennas 104a to 104i. The wiring width of segments 130a to 130r is 30 μm and the wiring length is 15 μm. When viewed from above, segments 130a to 130r overlap with antennas 104a to 104i, and the overlapping area for all antennas is 30 μm × 5 μm. In Figure 20, segments 130g and 130h and antenna 104d are at the same potential when driven, so no capacitance occurs in the second insulator 108 between segments 130g and 130h and antenna 104d. Therefore, by making the overlapping region equal for all antennas, the oscillation frequency shift between antennas due to factors other than wiring resistance is avoided. Note that in Figure 20, L'' = 5 μm. Here, the vertical direction is the direction in which antennas 104d and 104g are positioned relative to antenna 104a in Figure 17 (the up-down direction of the paper in the example). The horizontal direction is the direction in which antennas 104b and 104c are positioned relative to antenna 104a in Figure 17 (the left-right direction of the paper in the example).

[0085] The wiring widths of segments 105a to 105f increase segment by segment as they move away from pad 110a. Similarly, the wiring widths of segments 114a to 114x increase segment by segment as they move away from pad 110a. The wiring lengths of segments 129a to 129r increase segment by segment as they are closer to pad 110a. The wiring lengths of segments 105a to 105f and segments 114a to 114x are all 300 μm. In FIG. 18, the wiring length Lca of segment 105a, the wiring length Lcd of segment 105d, the wiring length La of segment 114a, and the wiring length Lm of segment 114m are shown. Also, in this embodiment, it is assumed that the resistivity and the film thickness are the same in all segments. Let the wiring widths of segments 105a to 105f be Wca to Wcf respectively. At this time, in the horizontal direction, in the relationship of Wca, Wcb, Wcc, Wca < Wcb < Wcc, and in the vertical direction, in the relationship of Wcd, Wce, Wcf, Wcd < Wce < Wcf. Let the wiring widths of segments 114a to 114x be Wa to Wx respectively. Although only Wa is shown in the figure, Wb to Wx are also wiring widths defined in the same way. At this time, in the vertical direction, in the relationship of Wa, Wd, Wg, Wj, Wa < Wd < Wg < Wj, in the relationship of Wb, We, Wh, Wk, Wb < We < Wh < Wk, and in the relationship of Wc, Wf, Wi, Wl, Wc < Wf < Wi < Wl. Similarly, in the vertical direction, in the relationship of Wm, Wq, Wu, Wm < Wq < Wu, in the relationship of Wn, Wr , Wn < Wr < Wv in the relationship of Wn, Wr, Wv, Wo < Ws < Ww in the relationship of Wo, Ws, Ww, and Wp < Wt < Wx in the relationship of Wp, Wt, Wx. Also, in the horizontal direction, in the relationship of Wa, Wb, Wc, Wa < Wb < Wc, in the relationship of Wd, We, Wf, Wd < We < Wf, in the relationship of Wg, Wh, Wi, Wg < Wh < Wi, and in the relationship of Wj, Wk, Wl, Wj < Wk < Wl. Similarly, in the horizontal direction, in the relationship of Wm, Wn, Wo, Wp, Wm < Wn < Wo < Wp, in the relationship of Wq, Wr, Ws, Wt, Wq < Wr < Ws < Wt, and in the relationship of Wu, Wv, Ww, Wx, Wu < Wv < Ww < Wx.

[0086] Similarly, as shown in the figure, the wiring lengths of segments 129a to 129r are L'a to L'r, respectively. Although only L'a is shown in the figure, the wiring lengths of L'b to L'r are similarly defined. In this case, in the vertical direction, the relationship between L'a, L'g, and L'm is L'a>L'g>L'm, the relationship between L'b, L'h, and L'n is L'b>L'h>L'n, and the relationship between L'c, L'i, and L'o is L'c>L'i>L'o. Similarly, in the vertical direction, the relationship between L'd, L'j, and L'p is L'd>L'j>L'p, the relationship between L'e, L'k, and L'q is L'e>L'k>L'q, and the relationship between L'f, L'l, and L'r is L'f>L'l>L'r. Furthermore, in the horizontal direction, the relationship between L'a, L'b, L'c, L'd, L'e, and L'f is L'a>L'b>L'c>L'd>L'e>L'f. Similarly, in the horizontal direction, the relationship between L'g, L'h, L'i, L'j, L'k, and L'l is L'g>L'h>L'i>L'j>L'k>L'l. Similarly, in the horizontal direction, the relationship between L'm, L'n, L'o, L'p, L'q, and L'r is L'm>L'n>L'o>L'p>L'q>L'r. Also, the wiring width of segments 129a to 129r is W'a to W'r. Although only W'a is shown in the diagram, W'b to W'r are similarly defined wiring widths. Furthermore, the resistivity and film thickness of the bias lines 105a to 105f, which are common to all antennas, and the segments 114a to 114x and 115a to 115r of the bias lines, which are individual to each antenna, are assumed to be the same. Table 1 shows the correspondence between each segment and its dimensions, and Table 2 shows Wca to Wcf, Wa to Wx, and W'a to W'r and L'a to L'r. Note that in the resistance calculation, the combined resistance of the negative resistance element 101 and antenna 104 in series is set to 30Ω. The values ​​shown in Table 2 ensure that the voltage applied to all antennas is equal to each other. [Table 1] [Table 2]

[0087] Therefore, with the oscillator element according to Example 8, even when the number of two-dimensional arrays increases compared to Example 7, it is possible to equalize the voltage drop between antennas while suppressing an increase in wiring width and wiring length by arranging the wiring in a grid pattern and forming two layers of wiring. [Explanation of symbols]

[0088] 102 Substrate, 101a~101i Negative Resistors, 104a~104i Antenna, 110,110a,110b Pads, 105,106a~106c,114a~114i,115a~115i Bias Lines

Claims

1. A substrate; a plurality of negative resistance elements electrically connected to the substrate; a plurality of antennas, each of which has at least one of the plurality of negative resistance elements and transmits or receives electromagnetic waves; a pad electrically connected to a power supply for supplying power to the plurality of antennas; a conductor electrically connecting the pad and the plurality of antennas; having the conductor is composed of a wiring common to the plurality of antennas and individual wiring from the common wiring to each of the plurality of antennas; The individual wiring includes at least two individual wirings; The at least two individual wirings have at least one of a cross-sectional area, a resistivity, and a length that differ from each other depending on a position on the substrate of an antenna connected to the at least two individual wirings so as to reduce a difference in wiring resistance that occurs based on a distance between the antenna connected to the at least two individual wirings and the pad. An oscillator device comprising:

2. 2. The oscillation element according to claim 1, wherein the closer a position of the antenna connected to the at least two individual wirings on the substrate is to the pad, the longer the length of the individual wirings.

3. 3. The oscillation element according to claim 1, wherein the closer a position of the antenna connected to the at least two individual wirings on the substrate is to the pad, the smaller a cross-sectional area of ​​the individual wirings becomes.

4. A plurality of the pads are arranged on the substrate, In order to reduce a difference in composite wiring resistance from the plurality of pads to the respective antennas, the at least two individual wirings are different from each other in at least one of a cross-sectional area, a resistivity, and a length depending on a position on the substrate of an antenna connected to the at least two individual wirings.

4. The oscillator according to claim 1, wherein the first and second electrodes are arranged in a first direction.

5. The oscillator element according to claim 1 , wherein the individual wirings are made of a plurality of materials.

6. The oscillator element according to claim 5, characterized in that the individual wirings are configured by electrically connecting a first wiring formed of a first material of the plurality of materials in a first layer on the substrate and a second wiring formed of a second material of the plurality of materials in a second layer to each other.

7. the individual wiring has a first segment that serves as wiring for at least two antennas of the plurality of antennas, and a second segment that electrically connects the first segment to each of the at least two antennas; At least one of a cross-sectional area, a resistivity, and a length of the first segment and the second segment is different from each other depending on a position on the substrate of an antenna connected to the at least two individual wirings.

7. The oscillator according to claim 1, wherein the first and second electrodes are arranged in a first direction.

8. 8. The oscillation element according to claim 1, wherein the distance between the plurality of antennas is equal to or less than the wavelength of an oscillated electromagnetic wave or an integer multiple of the wavelength.

9. 9. The oscillation element according to claim 1, wherein the antenna outputs an electromagnetic wave containing frequency components from 30 GHz to 30 THz.

10. 10. The oscillation element according to claim 1, wherein each of the plurality of negative resistance elements is a resonant tunneling diode.

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