Oscillator

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] The present disclosure relates to an oscillation element that oscillates electromagnetic waves in the terahertz wave frequency band. [Background technology]

[0002] Electromagnetic waves in the frequency range from 30 GHz to 300 THz are called terahertz waves. In the terahertz frequency band, many organic molecules, such as those in biomaterials, pharmaceuticals, and electronic materials, have absorption peaks due to their structure and state. Terahertz waves are also highly permeable to materials such as paper, ceramics, resin, and cloth. In recent years, research and development has been conducted on imaging and sensing technologies that take advantage of the characteristics of terahertz waves.

[0003] A well-known terahertz wave oscillator is one that integrates a negative resistance element, such as a resonant tunneling diode (RTD) or Gunn diode, with a resonator, which has electromagnetic gain in the terahertz region. Among these, a structure that integrates an RTD and an antenna is particularly promising as an oscillator that operates at room temperature in the frequency region around 1 THz.

[0004] However, in general, the output power of oscillators tends to decrease as the oscillation frequency increases. Therefore, arranging a structure in which negative resistance elements and resonators are integrated on the same substrate to form an array is used as an effective means to increase the output power. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-180049 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, the antennas are connected to each other using microstrip lines to achieve phase synchronization, thereby increasing output power. However, the lengths of the wiring electrically connected from the power supply (hereinafter referred to as "pad") to each antenna in the array do not necessarily match between the antennas, resulting in different wiring resistances between the antennas and differences in drive voltage between the antennas. Furthermore, it is known that when the drive voltage changes within the negative resistance region, the oscillation frequency changes. Therefore, differences in oscillation frequency between the antennas result in insufficient output power when the electromagnetic waves from each antenna in the array are combined.

[0007] Therefore, an object of the present disclosure is to provide a technique for matching the resistance values ​​of wiring connecting a pad for feeding power to an antenna among a plurality of antennas in an oscillation element. [Means for solving the problem]

[0008] In order to achieve the above object, the oscillation element according to the present disclosure comprises: A substrate; a plurality of negative resistance elements electrically connected to the substrate; a plurality of antennas, each of the plurality of antennas The plurality of negative resistance elements At least one negative resistance element a plurality of antennas for transmitting or receiving 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; and 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 comprises at least two individual wirings; The at least two individual wirings are Individual wiring and To reduce the difference in wiring resistance that occurs depending on the distance between the connected antenna and the pad, the at least two separate wires At least one of the cross-sectional area, resistivity, and length of the antenna is different from each other depending on the position on the substrate of the antenna to be connected to the R The present invention includes an oscillation element characterized by the above-mentioned. [Effects of the Invention]

[0009] According to the present disclosure, a sufficient output can be obtained when electromagnetic waves from antennas are combined in an oscillation element. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a top view schematically illustrating an example of an oscillation element according to an embodiment of the present invention; [Figure 2] Cross section along line A-A' in Figure 1 [Figure 3] Cross-sectional view taken along line B-B' in Figure 1 [Figure 4] FIG. 1 is a top view schematically illustrating an example of an oscillation element according to a first embodiment; [Figure 5] FIG. 10 is a top view schematically illustrating an example of an oscillation element according to Example 2. [Figure 6] FIG. 10 is a top view schematically illustrating an example of an oscillation element according to a third embodiment. [Figure 7] FIG. 10 is a top view schematically illustrating an example of an oscillation element according to Example 4. [Figure 8] FIG. 10 is a top view schematically illustrating an example of an oscillation element according to a fifth embodiment. [Figure 9] Cross-sectional view taken along line C-C' in Figure 8 [Figure 10] FIG. 13 is a top view schematically illustrating an example of an oscillation element according to a sixth embodiment. [Figure 11] 11A is a cross-sectional view taken along line DD' in FIG. 10, and FIG. 11B is a cross-sectional view taken along line BB' in FIG. [Figure 12] FIG. 13 is a top view schematically illustrating an example of an oscillation element according to Example 7. [Figure 13] FIG. 13A is a diagram schematically illustrating the structure of the RTD of the oscillation element according to this embodiment, FIG. 13B is a graph conceptually illustrating the energy barrier of the RTD and the resonant tunneling effect of electrons when a voltage is applied, and FIG. 13C is a graph illustrating an example of the current-voltage characteristics of the RTD. [Figure 14] Equivalent circuit of each wiring from the pad to the antenna in Figure 1 [Figure 15] A diagram showing the definition of resistor dimensions [Figure 16] 16A to 16L show the steps of producing an oscillation element according to this embodiment. [Figure 17] FIG. 17 is a top view schematically illustrating an example of an oscillation element according to an eighth embodiment. [Figure 18] FIG. 18 is a diagram showing a part of the oscillation element of FIG. [Figure 19] FIG. 19 is a perspective view showing a manufacturing process of an oscillation element according to Example 8. [Figure 20] FIG. 20 is a cross-sectional view taken along line F-F' in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the present disclosure is not limited to the following embodiments and can be modified as appropriate without departing from the spirit of the present disclosure. In addition, in the drawings described below, parts having the same functions are designated by the same reference numerals, and their description may be omitted or simplified.

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

[0013] The oscillator 100 of this embodiment has an antenna structure for transmitting or receiving electromagnetic waves. As shown in Figures 2 and 3, the oscillator 100 includes a substrate 102, a ground metal (GND) 103, a negative resistance element 101a, a first insulator 107, a second insulator 108, and a gate electrode 109. Furthermore, the oscillator element 100 has antennas 104a to 104c and bias lines 105, 106a to 106c for transmitting or receiving electromagnetic waves. In this embodiment, the plurality of antennas 104a to 104c are arranged in an array on the substrate 102. The antennas 104a to 104c are electrically connected to pads 110 via bias line 105 (a common wiring for the antennas) and bias lines 106a to 106c (individual wiring for each antenna). Furthermore, the pads 110 are connected to a power supply 112 via wiring 111 including wire bonding.

[0014] The pad 110 serves to electrically connect the antenna to an external circuit of the oscillator 100, for example, to supply a predetermined voltage from the outside. The pad 110 is made of a conductor. Hereinafter, the pad is referred to as a pad for electrically connecting to an external power supply for feeding power to the antenna. More specifically, the pad is a pad for receiving a predetermined voltage from the outside, and may be a pad for supplying a predetermined voltage to the outside. In this embodiment, the predetermined voltage may be a ground voltage, a power supply voltage, a voltage from a voltage bias circuit, or the like.

[0015] In the oscillator 100, an InP substrate is used for the substrate 102, and a plurality of negative resistance elements 101a-101c are arranged on the substrate 102 as semiconductor multilayer films that generate terahertz waves, thereby obtaining gain in the frequency range of terahertz waves. Resonant tunneling diodes (RTDs) or Gunn diodes can be used as the negative resistance elements 101a-101c. In the following description, it is assumed, as an example, that the negative resistance elements 101a-101c are composed of RTDs.

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

[0017] As shown in FIG. 1, for antennas 104a to 104c, the antenna spacing between adjacent antennas is 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. If the antenna spacing d is set to an integer multiple of the wavelength of the oscillating electromagnetic wave or less, preferably less than 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 is set to an integer multiple of the wavelength of the oscillating electromagnetic wave or less.

[0018] The oscillation principle of the RTD oscillation element in this embodiment and the drive voltage dependency of the oscillation frequency will be described. First, the oscillation principle will be described using FIGS. 13A to 13C. FIG. 13A is a diagram showing an example of the structure of an RTD used in the RTD oscillation element. FIG. 13B is a diagram conceptually explaining the energy barrier of the RTD and the resonant tunneling effect of electrons when a voltage is applied. FIG. 13C is a diagram showing the current-voltage characteristics of the RTD. As shown in FIG. 13A, the RTD 118 is composed of a quantum well layer 117 and barrier layers 116a and 116b provided above and below the quantum well layer 117. The film thicknesses of the barrier layers 116a and 116b are thinner than the film thickness of the quantum well layer 117.

[0019] Collector 121 and electrode 122 are arranged on the upper layer of RTD 118, and emitter 120 and ground 119 are arranged on the lower layer. As shown in Figure 13B, when the driving voltage is increased by power supply 123, the electron level on the emitter 120 side eventually matches the resonance level of quantum well layer 117, and electrons pass through energy barrier 124 as shown by arrow 125 due to the resonant tunneling effect. As a result, current flows on the collector 121 side. When the driving voltage is further increased, the electron level on the emitter 120 side becomes higher than the resonance level, and electrons cannot pass through barrier layers 116a and 116b, resulting in a decrease in the current.

[0020] Region (voltage range) 126 shown in Figure 13C is the negative resistance region. Generally, in an LC oscillator circuit consisting 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 the resistance loss.

[0021] Next, we will explain the dependency of the oscillation frequency on the drive voltage. The capacitance of the RTD oscillation element including the antenna is C, and the inductance of the antenna is L. A Then, the oscillation frequency f0 of the RTD is calculated by the following equations (1) and (2).

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[0022] where C A is the capacitance of the antenna. C0 is the capacitance determined by the dielectric constant and area of ​​the RTD 118, and the film thickness including the RTD 118, the emitter 120, and the collector 121. C RTD is the capacitance of the RTD 118 that is taken into account when a voltage is applied in the negative resistance region.

[0023] L A and C A is independent of the driving voltage, and the change in C0 due to the driving voltage isRTD Therefore, the change in the RTD oscillation frequency f0 due to the change in the drive voltage is small enough to be ignored. RTD The driving voltage dependence of C RTD is the capacitance that occurs when electrons remain between the emitter 120 and the collector 121 for the electron delay time when a voltage is applied in the negative resistance region, and is the quantum mechanical tunneling time (t RTD ) and negative differential conductance (NDC).

[0024] t RTD Since both and NDC depend on the driving voltage, C RTD depends on the drive voltage, and as a result, the oscillation frequency f0 has a drive voltage dependency. RTD It is known that in the negative resistance region of an RTD, the current gradually increases near the voltage where it reaches its peak value, and then decreases sharply as the voltage increases. As a result, in the negative resistance region of an RTD, when the drive voltage changes, the oscillation frequency f0 changes sharply. Based on this principle, it is important to match the wiring resistance and drive voltage between antennas when arraying them.

[0025] In FIG. 1, for example, the resistance value of the wiring from the pad 110 to the antenna 104a is R a and the resistance value of the wiring from the pad 110 to the antenna 104c is R c As a result, the resistance value R a and resistance value R c 14 shows an 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 the series resistance of the resistor of the bias line 105 and the resistor of the bias line 106c In FIG. 14, the resistance of the bias line 106a is determined by R ad , the resistance value of the bias line 105 is R cc , the resistance value of the bias line 106c is R cd Then, R a =Rad and R c =R cc +R cd This becomes:

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

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[0027] Therefore, in Figure 14, R ad =R cd Then, R a <R c Therefore, the drive voltage is different between the antenna 104a and the antenna 104c. If the resistivity, cross-sectional area, and length of the common wiring are fixed, R a and R c To match R cd =R ad -R cc R so that cd and R adOne of them is changed relative to the other. When the resistivity and length are fixed, the cross-sectional area of ​​the bias line 106c is made larger than the cross-sectional area of ​​the 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, when the film thickness is fixed, the width of the bias line 106c is made larger than the width of the bias line 106a. When the width is fixed, the film thickness of the bias line 106c is made larger than the film thickness of the bias line 106. When the resistivity and cross-sectional area are fixed, the length of the bias line 106a is made longer than the length of the bias line 106. When the cross-sectional area and length are fixed, the resistivity can be effectively changed by forming both or one of the bias lines 106a and 106c from multiple types of materials.

[0028] In this embodiment, at least one of the parameters that determine the resistance value, namely, resistivity ρ, cross-sectional area S, and length 1, is set to a different value between at least one antenna and another antenna in the antenna array. That is, in order to reduce the difference in wiring resistance that occurs based on the distance between the antenna connected to each individual wiring and the pad, 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 a process for producing an oscillation element common to each of the following examples will be described with reference to Figures 16A to 16L. Figures 16A to 16F show cross-sectional views of the oscillation element 100 at each step taken along line A-A' in Figure 1, and Figures 16G to 16L show cross-sectional views of the oscillation element 100 at each step taken along line B-B' in Figure 1.

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

[0031] The above is the process for producing an oscillator common to the following examples. Note that additional steps in each example will be described in detail in the description of each example. The examples will be described below.

[0032] Example 1 An oscillation element according to Example 1 will be described with reference to FIG. 4. FIG. 4 is a top view schematically illustrating an example of the oscillation element according to Example 1. In the oscillation element according to this example, antennas are arranged in a 1×3 array on a second insulator 108, and each antenna is configured to be fed from one direction. As shown in the figure, the wiring width w of the bias lines 106a to 106c is 1×3. a ~w c By making the widths of the pads 110 and the antennas 104a to 104c different from each other, the wiring resistance from the pad 110 to the antennas 104a to 104c is made to be the same. Also, the bias line 105, which is the common wiring for each antenna, and the bias lines 106a to 106c, which are the individual wiring from the bias line 105 to each antenna, have the same resistivity and film thickness.

[0033] 4, the wiring width and wiring length of the bias line 105 are W and L, respectively, and the wiring length of the bias lines 106a to 106c is 1. In this embodiment, the width w of the bias line 106a is a The width w of the bias line 106b is set so that the wiring resistances from the pad 110 to the antennas 104a to 104c are equal to each other. b and the width of bias line 106c w c is changed. More specifically, the cross-sectional area of ​​the bias lines 106a to 106c is set to become smaller as the positions on the substrate 102 of the antennas 104a to 104c connected to the bias lines 106a to 106c, respectively, are closer to the pad 110. In the case of FIG. 4, the antennas 104b and 104a are positioned closer to the pad 110 than the antenna 104c, and the antenna 104a is positioned closer to the pad 110 than the antenna 104b. Therefore, the width w of the bias lines 106a to 106c a , w b、 w c But w a <w b <w c It is set so that:

[0034] When the wiring resistances from the pad 110 to the antennas 104a to 104c are the same, the resistance of the antenna 104b is b and w a The relationship between w and w is given by the following equation (4): c and w a The relationship is given by the following equation (5).

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[0035] In this embodiment, for example, L=500 μm, l=200 μm, W=600 μm, and w a = 80 μm, w b = 122 μm, w c = 240 μm.

[0036] Example 2 Second Embodiment Next, an example of an oscillation element according to a second embodiment will be described with reference to Fig. 5. Fig. 5 is a top view schematically illustrating the example of an oscillation element according to a second embodiment.

[0037] In this embodiment, similar to the first embodiment, the antennas are arranged in a 1×3 array on the second insulator 108. In this embodiment, each antenna is configured to be fed from two directions, above and below the antenna, on the second insulator 108. As shown in the figure, the wiring width w of the bias lines 106a1 to 106c1, which are the individual wiring for each antenna, is a1 ~w c1 Similarly, the wiring width w of the bias lines 106a2 to 106c2, which are the individual wirings for each antenna, a2 ~w c2 are set to different widths. This makes the wiring resistance from the pad 110 to the antennas 104a to 104c the same. Also, the bias line 105, which is the common wiring for each antenna, and the bias lines 106a to 106c, which are the individual wiring from the bias line 105 to each antenna, have the same resistivity and film thickness.

[0038] 5, the wiring width and wiring length of the bias lines 105a and 105b are W and L, respectively, and the wiring length of the bias lines 106a1 to 106c2 is 1. In this embodiment, since each antenna is fed with power from two directions, above and below the antenna, on the second insulator 108, due to the symmetry of the feeding directions to the antennas, a1 =w a2 , w b1 =w b2 , w c1 =w c2 In this embodiment, w a1 =w a2 is fixed, and the wiring resistances from the pad 110 to the pads 104a to 104c are set to match each other. b1 (=w b2 ) and w c1 (=w c2) is changed. More specifically, similar to the first embodiment, the cross-sectional areas of the bias lines 106a1 to 106c1 are set to become smaller as the positions on the substrate 102 of the antennas 104a to 104c connected to the bias lines 106a1 to 106c1 are closer to the pad 110. Furthermore, the cross-sectional areas of the bias lines 106a2 to 106c2 are set to become smaller as the positions on the substrate 102 of the antennas 104a to 104c connected to the bias lines 106a2 to 106c2 are closer to the pad 110.

[0039] When the wiring resistances from the pad 110 to the pads 104a to 104c are the same, the following is true for the antenna 104b: b1 and w a1 The relationship between w and w is given by the following equation (6): c1 and w a1 The relationship is given by the following equation (7).

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[0040] In this embodiment, for example, L=500 μm, l=200 μm, W=600 μm, and w a1 =w a2 = 80 μm, w b1 =w b2 = 122 μm, w c1 =w c2 = 240 μm.

[0041] Therefore, according to the oscillation element of Example 2, it is possible to match the wiring resistance for each antenna even when the number of power feeding directions for the antennas is increased compared to Example 1. Note that in this example, the power feeding direction for each antenna is the vertical direction, but the power feeding direction is not limited to the vertical direction.

[0042] Example 3 Next, an example of an oscillation element according to Example 3 will be described with reference to Fig. 6. Fig. 6 is a top view schematically illustrating an example of an oscillation element according to Example 3.

[0043] In this embodiment, similarly to the first and second embodiments, antennas are arranged in a 1×3 array on the second insulator 108. In this embodiment, a plurality of pads are arranged on the substrate 102. Furthermore, on the second insulator 108, power is supplied to the bias line 105 from two directions, left and right of the bias line 105, via pads 110a and 110b. Furthermore, the wiring width w of the bias lines 106a to 106c is a ~w c is set to a width according to the wiring length from the pad 110a or pad 110b to the antennas 104a to 104c. This allows the wiring resistances from the pads 110a and 110b to the antennas 104a to 104c to be matched. Here, due to the symmetry of the power supply direction with respect to the bias line 105, w a =w c It is also assumed that the bias line 105, which is common wiring for each antenna, and the bias lines 106a to 106c, which are individual wiring from the bias line 105 to each antenna, have the same resistivity and film thickness.

[0044] 6, the wiring width and wiring length of the bias line 105 are W and L, respectively, and the wiring length of the bias lines 106a to 106c is l. a (=w c ) is fixed, and the wiring resistances from the pads 110a and 110b to the antennas 104a to 104c are set to match each other. b Change the

[0045] The combined wiring resistance from the pads 110a and 110b to the antenna 104a is R a , the combined wiring resistance from the pads 110a and 110b to the antenna 104b is 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, for example, L=500 μm, l=200 μm, W=600 μm, and w a =w c = 60 μm, R a =R b When it becomes b = 62 μm.

[0047] In the third embodiment, in order to reduce the difference in the combined wiring resistance from the multiple pads to the respective antennas, the respective wirings are different from one another in at least one of the cross-sectional area, resistivity, and length depending on the position on the substrate of the antenna connected to each wiring. Therefore, according to the oscillation element of the third embodiment, even if the number of pads that feed power to the bias line 105 is changed as shown in FIG. 6, it is possible to make the wiring resistance of each antenna consistent.

[0048] Example 4 Next, an example of an oscillation device according to a fourth embodiment will be described with reference to FIG. 10 is a top view schematically illustrating an example of an oscillation element according to Example 4. FIG.

[0049] In this embodiment, similarly to the first to third embodiments, the antennas are arranged in a 1×3 array in the second insulator 108. In this embodiment, the second insulator 108 is configured to feed power to the antennas 104a to 104c from one direction. In addition, the wiring length l of the bias lines 106a to 106c is a ~l care set to different wiring lengths. This makes the wiring resistance from the pad 110 to the antennas 104a to 104c the same. Also, the bias line 105, which is the common wiring for each antenna, and the bias lines 106a to 106c, which are the individual wiring from the bias line 105 to each antenna, are set to have the same resistivity and film thickness.

[0050] In FIG. 7, the wiring width and wiring length of the bias line 105 are W and L, respectively, and the wiring width of the bias lines 106a to 106c is w a =w b =w c In this example, l c and fix the wiring resistance from the pad 110 to the antennas 104a to 104c so that they match each other. a and l b When the wiring resistances from the pad 110 to the antennas 104a to 104c are the same, the following is true for the antenna 104a: a and c The relationship between l is given by the following equation (10): b and c The relationship is given by the following equation (11).

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[0051] In this embodiment, for example, L=500 μm, W=600 μm, and w a =w b= w c = 80 μm, l c = 200 μm, then l a = 333 μm, l b = 267 μm.

[0052] Therefore, compared to the first embodiment, the oscillation element according to the fourth embodiment makes it possible to match the wiring resistance for each antenna even if the wiring width or wiring length of the wiring connected to the antenna is changed.

[0053] Example 5 Next, an example of an oscillation element according to Example 5 will be described with reference to Fig. 8 and Fig. 9. Fig. 8 is a top view schematically showing the example of the oscillation element according to Example 5. Fig. 9 is a cross-sectional view taken along line CC' in Fig. 8.

[0054] In this embodiment, similarly to the first to fourth embodiments, the antennas are arranged in a 1×3 array in the second insulator 108. In this embodiment, the second insulator 108 is configured to feed power to the antennas 104a to 104c from one direction. In addition, the film thickness t a ~t c are set to different film thicknesses. This makes the wiring resistances from the pad 110 to the antennas 104a to 104c the same. Also, the bias line 105, which is the common wiring for each antenna, and the bias lines 106a to 106c, which are the individual wiring from the bias line 105 to each antenna, have the same resistivity.

[0055] In FIG. 8, the wiring width and wiring length of the bias line 105 are W and L, respectively. The wiring width of the wire lines 106a to 106c is w a =w b =w c In addition, the thickness of the bias line 105 is T. In this embodiment, the thickness of the bias line 106a is t a The film thickness t of the bias line 106b is set so that the wiring resistances from the pad 110 to the antennas 104a to 104c are equal to each other. b and the film thickness t of the bias line 106c c In this embodiment, the cross-sectional area of ​​the bias lines 106a to 106c is made smaller for the antennas 104a to 104c that are located closer to the pad 110, so that the wiring resistances from the pad 110 to the antennas 104a to 104c are made to match with each other. When the wiring resistances from the pad 110 to the antennas 104a to 104c are made to match with each other, t b and ta The relationship between the antenna 104c and the antenna 104b is given by the following equation (12): c and t a The relationship is given by the following equation (13).

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[0056] In this embodiment, for example, L=500 μm, l=200 μm, W=600 μm, and w a =w b= w c = 80 μm, t a If T = 500 nm, t b = 750 nm, t c = 1500 nm.

[0057] Therefore, in comparison with the first embodiment, the oscillation element according to the fifth embodiment makes it possible to match the wiring resistance between the antennas even if the film thickness of the wiring connected to the antennas is changed.

[0058] Example 6 Next, an example of an oscillation element according to Example 6 will be described with reference to Fig. 10, Fig. 11A, and Fig. 11B. Fig. 10 is a top view schematically showing an example of an oscillation element according to Example 6. Fig. 11A is a cross-sectional view taken along line DD' in Fig. 10, and Fig. 11B is a cross-sectional view taken along line BB' in Fig. 10.

[0059] In this embodiment, similarly to embodiments 1 to 5, antennas are arranged in a 1×3 array in second insulator 108. In this embodiment, second insulator 108 is configured to feed power to antennas 104a to 104c from one direction. In addition, bias lines from bias line 105 to antennas 104a and 104b are configured using a plurality of materials.

[0060] Specifically, as shown in FIG. 11A, bias line 106a is composed of bias lines 106a1 and 106a2 and bias line 113a connecting bias lines 106a and 106a2. Also, as shown in FIG. 11B, bias line 106b is composed of bias lines 106b1 and 106b2 and bias line 113b connecting bias lines 106b1 and 106b2. The bias lines 106a1 and 106a2 are made of different materials (first materials) than bias line 113a. Similarly, the bias lines 106b1 and 106b2 are made of different materials (first materials) than bias line 113b. The lengths of bias lines 106a-106c and 113a-113c are determined depending on the positions of antennas 104a-104c relative to pad 110. This allows the antenna to be The wiring resistances of 104a to 104c were made to match each other.

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

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

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

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

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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 = 130 μm, l = 200 μm, then l a '=120μm, l b '=60μm.

[0066] Therefore, according to the oscillation element of Example 6, it is possible to match the wiring resistance between the antennas even if the bias line is made of a plurality of types of material, as compared to Example 1. Also, by forming the bias line with a plurality of layers as in the oscillation element of Example 6, This is expected to increase the degree of freedom in arranging components on the board.

[0067] Example 7 Next, an example of an oscillation element according to Example 7 will be described with reference to Fig. 12. Fig. 12 is a top view schematically illustrating the example of an oscillation element 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 example, the antennas are arranged in a two-dimensional 3 x 3 array on the second insulator 108. Also, the second insulator 108 is configured so that the antennas 104a to 104i are fed from one direction (from below the paper in the illustrated example).

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

[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 a common wiring for each antenna, and segments 114a to 114i and segments 115a to 115i of the bias line, which are individual wirings from bias line 105 to each antenna, are the same.

[0071] In this embodiment, unlike the first to sixth embodiments, the bias line, which is an 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, the segments 114a to 114i are first segments that serve as wiring for at least two of the multiple antennas. Furthermore, the segments 115a to 115i are second segments that electrically connect the first segments to the respective antennas of the at least two antennas. In the case where the antennas are arranged in a two-dimensional array as shown in FIG. 12, attention is focused on the antennas 104a, 104b, and 104c. In FIG. 12, the resistance value of the wiring from the pad 110 to the segments 115a, 115b, and 115c of each antenna is defined as R a , R b , R c In this case, R a =R b =R c The wiring width w of the segments 114a, 114b, and 114c is a , w b , w c are determined respectively.

[0072] Further, as an example, attention is focused on antennas 104a and 104d. In FIG. 12, the resistance value of the wiring from pad 110 to segment 115d of antenna 104d is R d The resistance value of the segment 114a is R ad , the resistance value of the segment 114d is R dd In this case, since the wiring from the pad 110 to the segment 115a is common, R a <R d In this embodiment, the width w' of the segments 115a and 115d is set so that the resistance value of the wiring from the pad 110 to the antenna 104a is equal to the resistance value of the wiring from the bias line 105 to the antenna 104d. a and w' dFurthermore, the width w' of the segment 115d and the segment 115g is determined so that the resistance values ​​of the wiring from the pad 110 to each antenna are the same between the antennas 104d and 104g. d and w' g Similarly, the width w' of each segment is determined so that the resistance values ​​of the wiring from the pad 110 to each antenna are the same among the antennas 104b, 104e, and 104h and among the antennas 104c, 104f, and 104i. e , w' h , w' f , w' i As a result, in this embodiment, it is possible to adjust the widths of the segments 114a to 114i and the segments 115a to 115i of the bias line to match the wiring resistance from the pad 110 to each of the antennas 104a to 104i.

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

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

[0075] As shown in Fig. 12, L1 is the distance in the bias line 105 from the contact point between the bias line 105 and segment 114a on the pad 110 side to the contact point between the bias line 105 and segment 114b on the pad 110 side. L2 is the distance in the bias line 105 from the contact point between the bias line 105 and segment 114b on the pad 110 side to the contact point between the bias line 105 and segment 114c on the pad 110 side. The distance x between each of the segments 114a to 114i and each antenna is the same for all antennas, and is set to x = 10um. In this embodiment, one side d of each square antenna is A and the antenna spacing d is constant for each antenna. Therefore, L1 is d A , d, w a , w b Between L1=d A +d+w a -w b The relationship between L2 and d A ,d,w b , w c Between L2=d A +d+w b -w c In this embodiment, d A = 170 μm, d = 300 μm.

[0076] First, the following equation (16) holds between the antennas 104a and 104b, and the following equation (17) holds between the antennas 104b and 104c, so that the wiring resistances of the antennas 104a, 104b, and 104c match. b = 105 μm, w c =113μm.

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[0077] Next, these w a , w b , w cBased on the value of w, the widths of the segments 114d, 114e, 114f, 114g, 114h, and 114i extending in the vertical direction are set so that they become wider as they move away from the pad 110. d = 150 μm, w e = 170 μm, w f = 190 μm, w g = 200 μm, w h = 220 μm, w i = 240 μm. Then, based on the width values ​​of these segments, the wiring widths of segments 115d, 115e, 115f, 115g, 115h, and 115i are determined so that the wiring resistances of adjacent antennas in the vertical direction are the same. For example, the relationship between antennas 104a and 104d is as follows:

number

[0078] Therefore, according to the oscillation element of the seventh embodiment, even if the antennas are arranged in a two-dimensional array on the substrate, unlike the first embodiment, it is possible to match the wiring resistance between the antennas.

[0079] In the above description of the seventh embodiment, the widths, i.e., cross-sectional areas, of the segments 114a to 114i and the segments 115a to 115i are configured to differ from one another 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 resistivities and lengths of the segments 114a to 114i and the segments 115a to 115i may be configured to differ from one another depending on the positions of the antennas 104a to 104i relative to the pad 110.

[0080] Example 8 Next, an example of an oscillation element according to Example 8 will be described with reference to Fig. 17 to Fig. 20. Fig. 17 is a top view schematically showing an example of an oscillation element according to Example 8, Fig. 18 is a top view with a part cut out from Fig. 17, and Fig. 19 is a perspective view of a manufacturing step that is characteristic of this example, in the manufacturing process shown in Fig. 16. Fig. 20 shows a cross-sectional view taken along line F-F' in Fig. 18.

[0081] In this embodiment, as shown in Fig. 17, antennas are arranged in a two-dimensional 6 x 6 array on the second insulator 108. Also, the second insulator 108 is configured so that power is fed to each antenna from four directions. That is, similar to the seventh embodiment, bias lines, which are individual wiring 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 Fig. 17, the wiring resistance is adjusted only with the 3x3 array shown in Fig. 18. Fig. 17 shows only pads 110a to 110d, wirings 111a to 111d including wire bonding, power supplies 112a to 112d, negative resistance elements 101a to 101i, and antennas 104a to 104i. In Fig. 17, the X-X' plane The four 3×3 array regions are arranged symmetrically with respect to the YY′ plane, and a top view of the 3×3 array including the pad 110a is shown in FIG.

[0083] In this embodiment, the bias line serving as a common wiring is composed of segments 105a to 105f, and the bias line serving as a wiring to each antenna is divided into segments 114a to 114x and segments 115a to 115r. As shown in FIG. 19, the bias line serving as a common wiring and the bias line serving as a wiring to 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 segments constituting the first wiring and the segments constituting the second wiring are given the same reference numerals. The first wiring (the portion indicated by 191 in the figure) is formed in the process shown in FIGS. 16D and 16J. The second wiring (the portion indicated by 193 in the figure) is formed in the process shown in FIGS. 16F and 16L. The first wiring and the second wiring are connected by a second contact hole (the portion indicated by 192 in the figure) formed in the process shown in FIGS. 16E and 16K.

[0084] The segments 114a to 114x are arranged in a grid pattern, with segments 114a to 114l extending horizontally above and below each antenna, and segments 114m to 114x extending vertically to the left and right of each antenna. Segments 115z (z = a to r) are further divided into segments 129z (z = a to r) and segments 130z (z = a to r). Segments 115a to 115r extend horizontally from segments 114m to 114x, respectively, and segments 130a to 130r connect to antennas 104a to 104i. The wiring width of the 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 in an area measuring 30 μm x 5 μm. In FIG. 20, segments 130g and 130h and antenna 104d are at the same potential when driven, so no capacitance is generated in the second insulator 108 between segments 130g and 130h and antenna 104d. Therefore, by making the overlapping area equal for all antennas, deviations in oscillation frequency between antennas due to factors other than wiring resistance are avoided. Note that in FIG. 20, L'' = 5 μm. Here, the vertical direction is the direction in which antennas 104d and 104g are arranged relative to antenna 104a in FIG. 17 (the up-down direction on the paper in the example). The horizontal direction is the direction in which antennas 104b and 104c are arranged relative to antenna 104a in FIG. 17 (the left-right direction on 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 for 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. While only L'a is shown in the figure, L'b to L'r are also defined as wiring lengths. 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. Furthermore, the wiring widths of segments 129a to 129r are designated as W'a to W'r. Note that although only W'a is shown in the figure, W'b to W'r are similarly defined wiring widths. Also, bias lines 105a-105f, which are common wiring to each antenna, and segments 114a-114x and segments 115a-115r of the bias lines, which are individual wiring to each antenna, have the same resistivity and film thickness. Table 1 shows the correspondence between each segment and its dimensions, and Table 2 shows Wca-Wcf, Wa-Wx, W'a-W'r, and L'a-L'r. When calculating the resistance values, the combined resistance of the series connection of negative resistance element 101 and antenna 104 is set to 30 Ω. The values ​​shown in Table 2 ensure that the voltages applied to all antennas are equal to each other. [Table 1] [Table 2]

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

[0088] 102 substrate, 101a to 101i negative resistance elements, 104a to 104i antennas, 110, 110a, 110b pads, 105, 106a to 106c, 114a to 114i, 115a to 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 negative resistance element 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; and 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 comprises 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 the position on the substrate of the 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 oscillation element characterized by:

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

4. A plurality of the pads are arranged on the substrate, 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 the position on the substrate of the antenna connected to the at least two individual wirings so as to reduce a difference in composite wiring resistance from the plurality of pads to the respective antennas.

4. The oscillator according to claim 1, wherein the first and second electrodes are electrically connected to each other.

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

6. The oscillation element described in claim 5, characterized in that the individual wiring is configured by electrically connecting a first wiring formed of a first material of the plurality of materials on a first layer on the substrate and a second wiring formed of a second material of the plurality of materials on a second layer.

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 differs from each other depending on a position on the substrate of the antenna connected to the at least two individual wirings.

7. The oscillator according to claim 1, wherein the first and second electrodes are electrically connected to each other.

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 the oscillated electromagnetic wave or an integer multiple of the wavelength.

9. 9. The oscillator element according to claim 1, wherein the antenna outputs an electromagnetic wave containing frequency components in the range of 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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