Oscillating element and detection system

Abstract

To provide an oscillation element with a higher degree of freedom in selectable oscillation frequency without adding new components in a single oscillation element.SOLUTION: An oscillation element 100 has a substrate 101, a plurality of oscillation structures 102a to 102c, and a power feeding structure 103. The power feeding structure has a power supply 106, and a bias supply part 107 that supplies a bias to the plurality of oscillation structures. The oscillation structures have antennas 104a to 104c, and N semiconductor elements 105a to 105d electrically connection with the antennas. The semiconductor elements have negative resistance characteristics at driving by the power feeding structure. Among the N semiconductor elements in the oscillation structures, P semiconductor elements are connected in parallel with each other; S semiconductor elements are connected in series with each other; F semiconductor elements are supplied with a bias in a forward direction; and R semiconductor elements are supplied with a bias in a reverse direction. The semiconductor element included in at least any one oscillation structure has current-voltage characteristics asymmetrical to each other under the forward-direction bias and the reverse-direction bias.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technology disclosed herein relates to an oscillation element and a detection system having a negative resistance element and an antenna. [Background technology]

[0002] Electromagnetic waves in the frequency range from 30 GHz to 30 THz are called terahertz waves. In the terahertz frequency range, 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, it is generally difficult to significantly change the oscillation frequency of such an oscillation element, and in particular, in order to investigate multiple spectra inside a substance for the purpose of substance identification, it has been necessary to use multiple oscillation elements to oscillate at different oscillation frequencies. Therefore, technologies disclosed in Patent Documents 1 and 2 have been proposed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-49692 [Patent Document 2] Patent Application No. 2016-517795 Summary of the Invention [Problem to be solved by the invention]

[0006] The invention disclosed in Patent Document 1 enables switching of the oscillation frequency with a single element by asymmetrically adjusting the thickness of the thickness adjustment layers above and below the RTD gain medium and by incorporating a bias voltage polarity switching mechanism. However, due to the inherent structure of the RTD, only two frequencies can be selected with a single element, and these selectable frequencies are fixed. The invention disclosed in Patent Document 2 also provides a compact terahertz oscillator with continuously variable frequency even at room temperature by arranging a varactor diode, whose capacitance changes continuously with voltage sweep, in parallel. However, this method has the drawback of requiring additional manufacturing steps due to the addition of a new component, the varactor diode, and of generating output loss from the oscillator element due to the varactor diode.

[0007] In view of the above, the technique disclosed herein provides an oscillation element that has a higher degree of freedom in selectable oscillation frequencies without adding new components to a single oscillation element. [Means for solving the problem]

[0008] The oscillation element according to the technology disclosed herein is A substrate; a plurality of oscillation structures provided on the substrate for transmitting or receiving electromagnetic waves; and a power supply structure for electrically driving the plurality of oscillation structures. and the power supply structure includes a power source and a bias supply unit that supplies a bias to the plurality of oscillation structures; the oscillation structure includes one antenna and N (N≧1) semiconductor elements electrically connected to the antenna; The semiconductor elements have negative resistance characteristics when driven by the power supply structure, and P (P≧0) of the N elements are connected in parallel with each other, S (S≧0) are connected in series with each other, and when the direction of current flowing vertically upward with respect to the substrate is defined as the forward direction, F (F≧0) elements are supplied with a bias in the forward direction, and R (R≧0) elements are supplied with a bias in the reverse direction, the semiconductor element of at least one of the oscillation structures has current-voltage characteristics that are asymmetric between a forward bias and a reverse bias, At least one of N, P, S, F, and R is different between the different oscillation structures. The present invention includes an oscillation element characterized by the above-mentioned.

[0009] In addition, the oscillation element according to the technology disclosed herein is A substrate; a plurality of oscillation structures provided on the substrate for transmitting or receiving electromagnetic waves; and a power supply structure for electrically driving the plurality of oscillation structures. and the power supply structure includes a power source, a bias supply unit that supplies a bias to the plurality of oscillation structures, and a control unit that controls the supply of the bias by the bias supply unit; the oscillation structure includes one antenna and N (N≧1) semiconductor elements electrically connected to the antenna; N elements are supplied with a bias by the operation of the control unit and have negative resistance characteristics, of the N elements, P (P≧0) elements are supplied with a bias by the operation of the control unit and are connected in parallel to each other, S (S≧0) elements are supplied with a bias by the operation of the control unit and are connected in series to each other, and when the direction of a current flowing vertically upward with respect to the substrate is defined as a forward direction, F (F≧0) elements are supplied with a bias in a forward direction by the operation of the control unit and R (R≧0) elements are supplied with a bias in a reverse direction by the operation of the control unit, the semiconductor element of at least one of the oscillation structures has current-voltage characteristics that are asymmetric between a forward bias and a reverse bias, At least one of N, P, S, F, and R is different between the different oscillation structures by the operation of the control unit. The present invention includes an oscillation element characterized by the above-mentioned.

[0010] In addition, the oscillation element according to the technology disclosed herein is A substrate; an oscillation structure provided on the substrate for transmitting or receiving electromagnetic waves, and a power supply structure for electrically driving the oscillation structure; and the power supply structure includes a power source, a bias supply unit that supplies a bias to the oscillation structure, and a control unit that controls the supply of the bias by the bias supply unit; the oscillation structure includes one antenna and N (N≧2) semiconductor elements electrically connected to the antenna; N elements are supplied with a bias by the operation of the control unit and have negative resistance characteristics, and of the N elements, P (P≧0) elements are supplied with a bias by the operation of the control unit and are connected in parallel with each other, S (S≧0) elements are supplied with a bias by the operation of the control unit and are connected in series with each other, and when the direction of the current flowing vertically upward with respect to the substrate is taken as the forward direction, F (F≧0) elements are supplied with a bias in the forward direction by the operation of the control unit, and R (R≧0 ) are supplied with a bias in the reverse direction by the operation of the control unit, the semiconductor element has current-voltage characteristics that are asymmetrical between a forward bias and a reverse bias, At least one of N, P, S, F, and R changes due to the operation of the control unit. The present invention includes an oscillation element characterized by the above-mentioned.

[0011] The detection system according to the technology disclosed herein comprises: The above oscillator element, a receiving element that receives a high frequency wave from the oscillation element; a processing circuit for processing signals from the receiving elements; The detection system includes: [Effects of the Invention]

[0012] According to the technology disclosed herein, it is possible to provide an oscillation element that has a high degree of freedom in selecting an oscillation frequency in a single element without adding any new components. [Brief explanation of the drawings]

[0013] [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] 1, a cross-sectional view taken along line A-A' in FIG. 1, a cross-sectional view taken along line F-F' in FIG. 9, and a cross-sectional view taken along line G-G' in FIG. 10. [Figure 3] Cross-sectional view of line B-B' in Figure 1 [Figure 4] Cross-sectional view of line C-C' in Figure 1 [Figure 5] 1A and 1B are top views schematically showing an example of an oscillation element according to this embodiment and an example of an oscillation element according to Example 4; [Figure 6] Cross-sectional view taken along line D-D' in Figure 5. [Figure 7] Cross-sectional view of line E-E' in Figure 5. [Figure 8] 1A to 1C are diagrams showing a process for producing an oscillation element according to this embodiment. [Figure 9] FIG. 1 is a top view schematically illustrating an example of an oscillation element according to a first embodiment; [Figure 10] FIG. 10 is a top view schematically illustrating an example of an oscillation element according to Example 2. [Figure 11] FIG. 10 is a top view schematically illustrating an example of an oscillation element according to a third embodiment. [Figure 12] Cross-sectional view taken along line H-H' in FIG. 11. [Figure 13] FIG. 10 is a diagram showing an equivalent circuit focusing on a semiconductor element in an oscillation element according to Example 3. [Figure 14] FIG. 10 is a diagram showing an equivalent circuit focusing on a semiconductor element in an oscillation element according to Example 4. [Figure 15] FIG. 10 is a top view schematically illustrating an example of an oscillation element according to a fifth embodiment. [Figure 16] 16 is a cross-sectional view taken along line II' in FIG. 15. [Figure 17] FIG. 13 is a top view schematically illustrating an example of an oscillation element according to a sixth embodiment. [Figure 18] 18 is a cross-sectional view taken along line J-J' in FIG. 17. [Figure 19] FIG. 13 is a diagram showing an equivalent circuit focusing on a semiconductor element in an oscillation element according to Example 6. [Figure 20] FIG. 13 is a top view schematically illustrating an example of an oscillation element according to Example 7. [Figure 21] 20. Cross-sectional view taken along line K-K' in FIG. 20. [Figure 22] FIG. 13 is a top view schematically illustrating an example of an oscillation element according to Example 8. [Figure 23] 23 is a cross-sectional view taken along line L-L' in FIG. 22. [Figure 24] FIG. 13 is a diagram showing an equivalent circuit focusing on a semiconductor element in an oscillation element according to Example 8. [Figure 25] FIG. 1 is a diagram showing an example of an equivalent circuit in an oscillation element according to an embodiment of the present invention; [Figure 26] FIG. 10 is a diagram showing another example of an equivalent circuit in the oscillation element according to the embodiment; [Figure 27] FIG. 1 is a diagram showing a camera system using an oscillation element according to the present embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0014] Preferred embodiments of the technology disclosed herein will be described below with reference to the drawings. The drawings are merely for the purpose of explaining the structure or configuration, and the dimensions of the illustrated members do not necessarily reflect the actual dimensions. In addition, the same members or components are designated by the same reference numerals in the drawings, and the following description of overlapping content will be omitted.

[0015] (Embodiment) The oscillation element according to this embodiment will be described with reference to FIGS. 1 to 7. FIGS. 1 and 5 are top views of the oscillation element, FIG. 2 is a cross-sectional view taken along line A-A' in FIG. 1, FIG. 3 is a cross-sectional view taken along line B-B' in FIG. 1, FIG. 4 is a cross-sectional view taken along line C-C' in FIG. 1, FIG. 6 is a cross-sectional view taken along line D-D' in FIG. 5, and FIG. 7 is a cross-sectional view taken along line E-E' in FIG. 5. Common features of this embodiment and all the following examples will be described. First, as shown in FIG. 3, pad 112a is connected to conductor 113a, and conductor 113a is connected to antenna 104a. Note that the connections between pads 112b and 112c, conductors 113b and 113c, and antennas 104b and 104c are similar. Second, pad 112d, which is not connected to conductor 113d, is connected to substrate low-resistance layer 115, as shown in FIG. 4. Third, the semiconductor elements 105a to 105e serving as negative resistance elements are resonant tunneling diodes, and the antennas 104a to 104c are patch antennas. The above are common features in this embodiment and all the following examples. Unless otherwise specified, these common features are the same in this embodiment and all the following examples, and their explanation may be omitted.

[0016] The oscillator 100 of this embodiment shown in FIGS. 1 to 4 includes a substrate 101, oscillator structures 102a to 102c for transmitting or receiving electromagnetic waves, and a feeding structure 103. In this embodiment, the electromagnetic waves include frequency components from 30 GHz to 30 THz. As shown in FIG. 2, the oscillator structure 102a includes an antenna 104a and a semiconductor element 105a, which are electrically connected to each other. The oscillator structure 102b includes an antenna 104b, a semiconductor element 105b, and a semiconductor element 105c. The antenna 104b, the semiconductor element 105b, and the semiconductor element 105c are electrically connected to each other, and the semiconductor element 105b and the semiconductor element 105c are electrically connected to each other in parallel via the antenna 104b. The oscillator structure 102c includes an antenna 104c, a semiconductor element 105d, and a semiconductor element 105e. Antenna 104c is electrically connected to semiconductor element 105d and semiconductor element 105e, and semiconductor element 105d and semiconductor element 105e are electrically connected to each other in series via conductor 113d.

[0017] The power supply structure 103 includes a power supply 106, a bias supply unit 107, and control units 108a-108c. The bias supply unit 107 includes wiring 111 including wire bonding, pads 112a-112d, and conductors 113a-113c. As shown in FIG. 3, the pad 112a and the conductor 113a are electrically connected to the antenna 104a. As shown in FIG. 4, the pad 112d is electrically connected to the substrate low-resistance layer 115. However, the portion of the substrate low-resistance layer 115 connected to the semiconductor element 105d is not connected to any of the pads 112a-112d. By turning on only the control unit 108a and turning off the control units 108b and 108c, it is possible to drive only the oscillation structure 102a. Similar operations can be used to drive only the oscillation structure 102b or only the oscillation structure 102c, or to drive multiple oscillation structures simultaneously.

[0018] 5 to 7, the oscillation element 100 of this embodiment includes a substrate 101, an oscillation structure 102a for transmitting or receiving electromagnetic waves, and a power supply structure 103. As shown in FIG. 6, the oscillation structure 102a includes an antenna 104a, a semiconductor element 105a, and a semiconductor element 105b, and the antenna 104a and the semiconductor element 105a are electrically connected to each other. The power supply structure 103 includes a power source 106, a bias supply unit 107, and control units 108a to 108c. The bias supply unit 107 includes wiring 111 including wire bonding and pads 11. 7, the pad 112c and the pad 112d are electrically connected to the substrate low resistance layer 115, and the pad 112c is electrically connected to the semiconductor element 105a via the substrate low resistance layer 115. The pad 112d is electrically connected to the semiconductor element 105b and the first insulator 109 via the substrate low resistance layer 115.

[0019] In the oscillation element 100 shown in FIGS. 5 to 7, when the control unit 108a is turned OFF, the control unit 108b is turned OFF, and the control unit 108c is turned ON, the semiconductor element 105b is electrically insulated. In this way, in the power supply structure, a portion of the bias supply unit is insulated by the operation of the control unit. Furthermore, when the control unit 108a is turned ON, the control unit 108b is turned OFF, and the control unit 108c is turned ON, the semiconductor element 105a and the semiconductor element 105b are electrically connected in parallel. When the control unit 108a is turned OFF, the control unit 108b is turned ON, and the control unit 108c is turned OFF, the semiconductor element 105a and the semiconductor element 105b are electrically connected in series.

[0020] As described above, the oscillation element 100 according to this embodiment is shown in Fig. 1 or Fig. 5, and the oscillation element 100 shown in Fig. 1 does not necessarily have to include the control units 108a to 108c. In addition, in the following description of the oscillation element according to each example, the same components as those described above will be denoted by the same reference numerals, and the description thereof will be omitted.

[0021] The principle of frequency variability of the oscillator 100 in this embodiment will be described. d , the antenna capacitance C a and the antenna inductance L a Using this, the oscillation frequency f0 of the LC circuit is expressed by the following equation (1). a is determined by the dielectric constant, area, and thickness of the insulator inserted between the antenna and the substrate.

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[0022] Therefore, at least the capacity C d The oscillation frequency f0 changes by changing the negative resistance element. In this embodiment, at least one of the "number," "number connected in parallel," "number connected in series," "number supplied with a forward bias," and "number supplied with a reverse bias" of the negative resistance elements constituting the LC circuit is intentionally changed.

[0023] First, the capacitance C changes depending on the number of negative resistance elements, the number of elements connected in parallel, and the number of elements connected in series. d The reason why changes in capacitance C d ) are connected in parallel with each other, the capacitance is PC d and S identical negative resistance elements (capacity C d ) are connected in parallel with each other, the capacitance is C d Next, the capacitance C d Explain why capacitance C changes. d has a negative differential conductance (NDC) dependency, and NDC has a drive voltage dependency of the negative resistance element. Therefore, when the forward direction is defined, if the current-voltage characteristics of the negative resistance element are asymmetric when a forward bias is applied and when a reverse bias is applied, the NDC changes when the bias is reversed, and the capacitance C d Therefore, out of the N negative resistance elements that make up the LC circuit, F elements are supplied with a forward bias (capacitance C d _F), R pieces are reverse biased (capacitance C d When F and R change, the capacitance C d changes.

[0024] Next, in this embodiment, the equivalent circuit shown in FIG. 25 is used, particularly when the number of semiconductor elements is small. N is N≧2, and S1 to S n The following explains the conditions that the cross-sectional area of ​​each semiconductor element must satisfy when it is composed of S k The (k=1 to n) semiconductor elements are composed of a single semiconductor element or single semiconductor elements connected in series with each other, and have negative resistance characteristics when driven by the power supply structure. k The semiconductor elements are C k (C k ≧0) semiconductor elements are connected in series with each other, and C k The semiconductor elements are C k≧2, and consists of single semiconductor elements connected in series with each other, k This semiconductor element has a positive resistance characteristic when driven by the power supply structure.

[0025] As shown in Figure 25, S k The semiconductor elements (k=1 to n) are single semiconductor elements or semiconductor elements E connected in series with each other. ik (i=1~S k ) and C k The semiconductor elements (k=1 to n) are single semiconductor elements or semiconductor elements F connected in series with each other. ik (i=1~C k ) The semiconductor element is configured with a driving voltage V min From V max and the driving voltage -V when the bias is supplied in the reverse direction min’ From -V max’ It has negative resistance characteristics only in the range of V min >0 and V max >0, V min’ <0 and V max’ <0. Under this condition, the semiconductor element E ik is driven in the negative resistance region, and all semiconductor elements E ik In order to apply a voltage equal to the capacitance of each semiconductor element, the cross-sectional area of ​​the semiconductor element is adjusted to satisfy the following three conditions: When the voltage fluctuates in the negative resistance region, the capacitance of each semiconductor element fluctuates minutely. Therefore, in this embodiment, an equal voltage is applied to all semiconductor elements in order to make it easier to adjust the capacitance.

[0026] The first condition is that for any k and any i, i', (i ≠ i', 1 ≦ i, i' ≦ S k ), semiconductor element E ik and semiconductor element E i’k The second condition is that for any k, k' (k ≠ k', 1 ≦ k, k' ≦ n), the voltages of the semiconductor element E ik and semiconductor element E ikThe third condition is that the voltages of the semiconductor element F are equal and driven at the voltage in the negative resistance region. ik is driven at a voltage in the positive resistance region. The first condition is satisfied by equation (2), the second condition is satisfied by equations (6) and (7), and the third condition is satisfied by equations (8) and (9).

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[0035] Here, the semiconductor element E ik The cross-sectional area of ​​A ik, resistivity is ρ, and film thickness is t. In this case, the semiconductor element E ik Resistance value R ik is R ik =ρt / A ik For any k and any i, i', (i ≠ i', 1 ≦ i, i' ≦ S k ), to satisfy the first condition, R ik =R i’k Therefore, the relationship of the formula (2) must be satisfied. ik By introducing the semiconductor element E ik The voltage applied to the

[0036] In addition, the semiconductor element F ik The cross-sectional area of ​​B ik , resistivity is ρ, and film thickness is t. In Figure 25, C k pieces+S k The combined resistance R of the semiconductor elements total From equations (2) and (3), the voltage of the power supply is expressed as V in When this is done, the semiconductor element E ik The voltage V applied to ik is expressed as equation (4), and the semiconductor element F ik The voltage V applied to ik ' is expressed as equation (5). From equation (4), the relationship between equations (6) and (7) must hold in order to satisfy the second condition. Similarly, the relationship between equations (8) and (9) must hold in order to satisfy the third condition.

[0037] Similarly, in this embodiment, as shown in the equivalent circuit of FIG. 26, in particular, N≧2, P1 to P m This section explains the conditions that the cross-sectional area of ​​each semiconductor element must satisfy when the device is composed of semiconductor elements. l The (l=1 to m) semiconductor elements are composed of a single semiconductor element or single semiconductor elements connected in parallel to each other, and have negative resistance characteristics when driven by the power supply structure.

[0038] As shown in Figure 26, P lThe semiconductor elements (l=1 to m) are either single semiconductor elements or semiconductor elements E jl (j=1~P l ) The semiconductor element is driven by a driving voltage V min From V max range and the driving voltage -V when the bias supply is in the reverse direction min’ From -V max’ It has negative resistance characteristics only in the range of V min >0 and V max >0, V min’ <0 and V max’ <0. Under this condition, the semiconductor element E jl is driven in the negative resistance region, and all semiconductor elements E jl In order to apply a voltage equal to l, l', and j (j=1 to P), the cross-sectional area of ​​the semiconductor element is adjusted to satisfy the following condition. When the voltage fluctuates in the negative resistance region, the capacitance of a single semiconductor element fluctuates minutely. Therefore, in this embodiment, in order to make it easier to adjust the capacitance, an equal voltage is applied to all semiconductor elements. The condition is that, for any l, l', and j (j=1 to P), l ) for (l ≠ l', 1 ≦ l, l' ≦ m) semiconductor element E jl and semiconductor element E jl’ The voltages are equal and the transistors are driven at a voltage in the negative resistance region.

[0039] Semiconductor element E jl The cross-sectional area of ​​A jl , resistivity is ρ, and film thickness is t. In this case, the cross-sectional area A jl , resistivity ρ, and film thickness t, the semiconductor element E jl Resistance value R jl is R jl =ρt / A jl In Figure 26, P l The combined resistance R_l of the semiconductor elements is given by equation (10), and from equation (10), P1 to P m The combined resistance R of the semiconductor elements total ' is expressed by equation (11). From equation (11), the voltage of the power supply is V in When P lThe voltage V applied to each semiconductor element l is expressed as equation (12). Then, the cross-sectional area A of the semiconductor element jl and A jl’ , P connected in series with each other m The voltage V applied to each semiconductor element in and V min , V max and V min’ , V max’ The relationship between equations (13) and (14) must be established for the oscillation elements 100. The above description applies to each oscillation element 100 in the following embodiments.

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[0045] 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 8A to 8F. Figures 8A to 8F show cross-sectional views of the oscillation element 100 at each step, taken along line A-A' in Figure 1.

[0046] In FIG. 8A, semiconductor elements 105a-105e are epitaxially grown on a substrate 101 and formed into a mesa shape by photolithography. In FIG. 8B, a substrate low-resistance layer 115 is processed by photolithography. In FIG. 8C, a first insulator 109 is formed on the semiconductor elements 105a-105e, the substrate high-resistance layer 114, and the substrate low-resistance layer 115, and first contact holes are formed by photolithography. In FIG. 8D, pads 112a-112d and conductors 113a-113d are formed by photolithography. In FIG. 8E, a second insulator 110 is formed, and second contact holes are formed by photolithography. In FIG. 8F, antennas 104a-104c are formed by photolithography. The above is the process for producing an oscillator common to the embodiments described below.

[0047] Example 1 Next, an oscillation element according to Example 1 will be described with reference to Fig. 9 and Fig. 2. Fig. 9 is a top view schematically showing an example of an oscillation element 100 according to Example 1, and Fig. 2 corresponds to a cross-sectional view taken along line F-F' in Fig. 9. In the oscillation element 100 according to this example, an oscillation structure 102a has an antenna 104a and a semiconductor element 105a, and the antenna 104a and the semiconductor element 105a are electrically connected to each other. An oscillation structure 102b has an antenna 104b and a semiconductor element 105a. The oscillation structure 102c includes an antenna 104c, a semiconductor element 105b, and a semiconductor element 105c. The antenna 104b, the semiconductor element 105b, and the semiconductor element 105c are electrically connected to each other, and the semiconductor element 105b and the semiconductor element 105c are electrically connected in parallel to each other via the antenna 104b. The oscillation structure 102c includes an antenna 104c, a semiconductor element 105d, and a semiconductor element 105e. The antenna 104c, the semiconductor element 105d, and the semiconductor element 105e are electrically connected to each other, and the semiconductor element 105d and the semiconductor element 105e are electrically connected to each other in series via the conductor 113d. In the substrate low-resistance layer 115, the connection portion with the semiconductor element 105d is not connected to any of the pads 112a to 112d. The power supply structure 103 has a power source 106 and a bias supply unit 107, and the bias supply unit 107 has wiring 111 including wire bonding, pads 112a to 112d, and conductors 113a to 113c.

[0048] In the oscillation device 100 of the first embodiment, the semiconductor elements 105a to 105e have negative resistance characteristics when driven by the power supply structure 103. The oscillation structures 102a to 102c each include one antenna and N (N≧1) semiconductor elements 105a to 105e electrically connected to the antenna. Of the N semiconductor elements, P (P≧0) semiconductor elements are connected in parallel, and S (S≧0) semiconductor elements are connected in series. In the example of FIG. 9, the direction of current flowing vertically upward (vertically upward in the plane of the paper) relative to the substrate 101 is defined as the forward direction. At this time, F (F≧0) semiconductor elements receive a bias in the forward direction, and R (R≧0) semiconductor elements receive a bias in the reverse direction. The same relationship between the forward and reverse directions in bias supply applies to other embodiments.

[0049] 9, a bias is supplied to the oscillation structures 102a to 102c in the forward direction. Furthermore, the case where N=1, P=0, S=0, F=1, and R=0 corresponds to the oscillation structure 102a, the case where N=2, P=2, S=0, F=2, and R=0 corresponds to the oscillation structure 102b, and the case where N=2, P=0, S=2, F=2, and R=0 corresponds to the oscillation structure 102c. Note that when a bias is supplied to the oscillation structures 102a to 102c in the reverse direction, the values ​​of F and R are swapped in each oscillation structure, and the values ​​of N, P, and S are the same.

[0050] In the oscillator 100 according to the first embodiment, the oscillator structures 102a to 102c can simultaneously transmit or receive electromagnetic waves of three different oscillation frequencies. a =80 [fF], capacitance C of the semiconductor elements 105a to 105e d = 15 [fF], and the oscillation frequency when a forward bias is supplied by any one of the semiconductor elements 105a to 105e that constitute the oscillation structure is 500 [GHz]. If the oscillation frequencies of the oscillation structure 102a, the oscillation structure 102b, and the oscillation structure 102c are f1, f2, and f3, respectively, then f1 = 500 [GHz], f2 = 465 [GHz], and f3 = 521 [GHz].

[0051] Example 2 Next, an oscillation element according to a second embodiment will be described with reference to FIGS. 10 and 2. FIG. 10 is a top view schematically illustrating an example of an oscillation element 100 according to the second embodiment, and FIG. 2 corresponds to a cross-sectional view taken along line G-G' in FIG. 10. In the oscillation element 100 according to this embodiment, an oscillation structure 102a includes an antenna 104a and a semiconductor element 105a, and the antenna 104a and the semiconductor element 105a are electrically connected to each other. An oscillation structure 102b includes an antenna 104b, a semiconductor element 105b, and a semiconductor element 105c. The antenna 104b, the semiconductor element 105b, and the semiconductor element 105c are electrically connected to each other, and the semiconductor element 105b and the semiconductor element 105c are electrically connected in parallel to each other via the antenna 104b. An oscillation structure 102c includes an antenna 104c, a semiconductor element 105d, and a semiconductor element 105e. The antenna 104c is electrically connected to the semiconductor element 105d and the semiconductor element 105e, and the semiconductor element 105d is electrically connected to the semiconductor element 105e in series via the conductor 113d. The connection portion of this is not connected to any of pads 112a to 112d. Power supply structure 103 has power sources 106a to 106f, bias supply unit 107, and control units 108a to 108f, and bias supply unit 107 has wiring 111 including wire bonding, pads 112a to 112d, and conductors 113a to 113c.

[0052] In the oscillator 100 of the second embodiment, the control units 108d to 108f can individually reverse the direction of the bias supplied to the oscillation structures 102a to 102c between the forward and reverse directions. Therefore, in the power supply structure of the second embodiment, the control unit operates to switch the power source connected to the semiconductor element or the oscillation structure. Furthermore, the control units 108a to 108c can also drive the oscillation structures 102a to 102c individually or simultaneously drive multiple oscillation structures. Therefore, in the power supply structure of the second embodiment, the control unit operates to select between individually driving multiple oscillation structures and simultaneously driving multiple oscillation structures.

[0053] In the oscillation device 100 of the second embodiment, the semiconductor elements 105a to 105e are supplied with a bias by the operation of the control units 108a to 108f of the power supply structure 103, and have negative resistance characteristics. The oscillation structures 102a to 102c each have one antenna and N (N≧1) semiconductor elements electrically connected to the antenna. Of the N semiconductor elements, P (P≧0) are connected in parallel, and S (S≧0) of the N semiconductor elements are connected in series. F (F≧0) receive a bias in the forward direction, and R (R≧0) receive a bias in the reverse direction.

[0054] 10, for example, it is assumed that the control units 108a to 108f are controlled to supply a bias to the oscillation structures 102a to 102c in the forward direction. In this case, N=1, P=0, S=0, F=1, and R=0 corresponds to the oscillation structure 102a, N=2, P=2, S=0, F=2, and R=0 corresponds to the oscillation structure 102b, and N=2, P=0, S=2, F=2, and R=0 corresponds to the oscillation structure 102c. It is also assumed that the control units 108a to 108f are controlled to supply a bias to the oscillation structures 102a to 102c in the reverse direction. In this case, the case where N=1, P=0, S=0, F=0, and R=1 corresponds to oscillation structure 102a, the case where N=2, P=2, S=0, F=0, and R=2 corresponds to oscillation structure 102b, and the case where N=2, P=0, S=2, F=0, and R=2 corresponds to oscillation structure 102c.

[0055] The oscillator 100 according to the second embodiment can transmit or receive electromagnetic waves of three different oscillation frequencies individually, or simultaneously. The control units 108d to 108f can reverse the direction of the bias supplied to each of the oscillator structures 102a to 102c. By turning on the control units 108a and 108d and turning off the control units 108b and 108c, it is possible to drive only the oscillator structure 102a. By operating the control units 108b and 108e, and the control units 108c and 108f in the same way, it is also possible to drive only the oscillator structure 102b or only the oscillator structure 102c. Furthermore, it is also possible to drive multiple oscillator structures simultaneously by the control units 108a to 108f. When a forward bias is supplied to the oscillator structures 102a to 102c by the control units 108d to 108f, the antenna capacitance C a =80 [fF], capacitance C of the semiconductor elements 105a to 105e when a forward bias is applied d = 15 [fF]. In addition, the oscillation frequency when a forward bias is supplied by any one of the semiconductor elements 105a to 105e that constitute the oscillation structure is set to 500 [GHz]. In this case, if the oscillation frequencies of the oscillation structure 102a, the oscillation structure 102b, and the oscillation structure 102c are f1, f2, and f3, respectively, then f1 = 500 [GHz], f2 = 465 [GHz], and f3 = 521 [GHz].

[0056] Example 3 Next, an oscillation element according to Example 3 will be described with reference to Figs. 11 to 13. Fig. 11 is a top view schematically showing an example of the oscillation element according to Example 3, and Fig. 12 is a top view of Fig. 11. 13 is a cross-sectional view taken along line H-H'. FIG. 13 is an equivalent circuit of the oscillator 100 according to Example 3, and for simplicity, attention is focused only on the semiconductor elements 105a to 105f. In the oscillator 100 according to this example, the oscillator structure 102a has an antenna 104a and a semiconductor element 105a, and the antenna 104a and the semiconductor element 105a are electrically connected to each other. Note that, in order to stabilize the formation process when forming the semiconductor element 105, electrically isolated semiconductor elements 105b are present so that the semiconductor elements are evenly arranged in pairs within the oscillator.

[0057] The oscillation structure 102b also includes an antenna 104b and semiconductor elements 105c-105d, and the antenna 104b and the semiconductor element 105c are electrically connected to each other. The oscillation structure 102c also includes an antenna 104c and semiconductor elements 105e-105f. The antenna 104c, the semiconductor elements 105e, and the semiconductor elements 105f are also electrically connected to each other, and the semiconductor elements 105e and 105f are electrically connected to each other in series via a conductor 113e. The conductor 113c is electrically connected to the semiconductor element 105d. The conductor 113e is electrically connected to the semiconductor element 105f. The pad 112f is electrically connected to the substrate low-resistance layer 115, and is electrically connected to the semiconductor elements 105a, 105b, 105c, 105d, and 105f and the first insulator 109 via the substrate low-resistance layer 115. The power supply structure 103 has a power source 106, a bias supply unit 107, and control units 108a to 108e, and the bias supply unit 107 has wiring 111 including wire bonding, pads 112a to 112f, and conductors 113a to 113e.

[0058] The semiconductor elements 105a to 105e are supplied with a bias by the operation of the control units 108a to 108e of the power supply structure 103, and have negative resistance characteristics. The oscillation structure of Example 3 also has one antenna and N (N≧1) semiconductor elements electrically connected to the antenna. P (P≧0) of the N semiconductor elements are connected in parallel, and S (S≧0) of the N semiconductor elements are connected in series. F (F≧0) are supplied with a bias in the forward direction, and R (R≧0) are supplied with a bias in the reverse direction.

[0059] 11, a bias is supplied to the oscillation structures 102a to 102c in the forward direction. When the control unit 108a is turned ON, the oscillation structure 102a has an oscillation structure where N=1, P=0, S=0, F=1, and R=0. When the control units 108b and 108c are both turned ON, the oscillation structure 102b has an oscillation structure where N=2, P=2, S=0, F=2, and R=0. When the control unit 108d is turned ON and the control unit 108e is turned OFF, the oscillation structure 102c has an oscillation structure where N=2, P=0, S=2, F=2, and R=0. Note that when a bias is supplied to the oscillation structures 102a to 102c in the reverse direction, the values ​​of F and R are swapped in each oscillation structure, and the values ​​of N, P, and S are the same.

[0060] The oscillator 100 according to the third embodiment can transmit or receive electromagnetic waves of three different oscillation frequencies individually, or simultaneously. By turning on only the control unit 108a and turning off the control units 108b to 108e, it is possible to drive only the oscillation structure 102a. By operating the control units 108b and 108c and the control units 108d and 108e in the same manner, it is also possible to drive only the oscillation structure 102b or only the oscillation structure 102c. Furthermore, it is also possible to drive a plurality of oscillation structures simultaneously by the control units 108a to 108e. When a forward bias is supplied to the oscillation structures 102a to 102c by the control units 108d to 108f, the antenna capacitance C a =80 [fF], capacitance C of semiconductor elements 105a to 105f d = 15 [fF]. In addition, the oscillation frequency when a forward bias is supplied by any one of the semiconductor elements 105a to 105f that constitute the oscillation structure is set to 500 [GHz]. The oscillation frequency of the oscillation structure 102a when the control unit 108a is turned ON is set to f1, and the oscillation frequency of the oscillation structure 102b when both the control units 108b and 108c are turned ON is set to f2. In addition, the oscillation frequency of the oscillation structure 102c when the control unit 108d is turned ON and the control unit 108e is turned OFF is set to f3. In this case, f1 = 500 [GHz z], f2=465[GHz], and f3=521[GHz].

[0061] Example 4 Next, an oscillation element according to Example 4 will be described with reference to FIGS. 5 to 7 and 14. FIG. 5 is a top view schematically illustrating an example of an oscillation element according to Example 4, FIG. 6 is a cross-sectional view taken along line D-D' in FIG. 5, and FIG. 7 is a cross-sectional view taken along line E-E' in FIG. 5. FIG. 14 is an equivalent circuit of an oscillation element 100 according to Example 4, and for simplicity, focuses only on the semiconductor element 105. In the oscillation element 100 according to this example, the oscillation structure 102a includes an antenna 104a, a semiconductor element 105a, and a semiconductor element 105b, and the antenna 104a and the semiconductor element 105a are electrically connected to each other. The conductor 113b is electrically connected to the semiconductor element 105b. The pads 112c and 112d are electrically connected to the substrate low-resistance layer 115, and the pad 112c is electrically connected to the semiconductor element 105a via the substrate low-resistance layer 115. Pad 112d is electrically connected to semiconductor element 105b and first insulator 109 via substrate low-resistance layer 115. Power supply structure 103 includes power source 106, bias supply unit 107, and control units 108a-108c. Bias supply unit 107 includes wiring 111 including wire bonding, pads 112a-112d, and conductors 113a-113b. When control unit 108a is turned OFF, control unit 108b is turned OFF, and control unit 108c is turned ON, semiconductor element 105b is electrically insulated. When control unit 108a is turned ON, control unit 108b is turned OFF, and control unit 108c is turned ON, semiconductor element 105a and semiconductor element 105b are electrically connected in parallel. When control unit 108a is turned OFF, control unit 108b is turned ON, and control unit 108c is turned OFF, semiconductor element 105a and semiconductor element 105b are electrically connected in series.

[0062] In the oscillation device 100 of Example 4, the semiconductor elements 105a and 105b are supplied with a bias by the operation of the control units 108a to 108c of the power supply structure 103, and have negative resistance characteristics. The oscillation structure 102a also has one antenna and N (N≧1) semiconductor elements electrically connected to the antenna. Of the N semiconductor elements, P (P≧0) are connected in parallel, and S (S≧0) of the N semiconductor elements are connected in series. F (F≧0) are supplied with a bias in the forward direction, and R (R≧0) are supplied with a bias in the reverse direction.

[0063] 5, a bias is supplied to the oscillation structure 102a in the forward direction. When the control unit 108a is turned OFF, the control unit 108b is turned OFF, and the control unit 108c is turned ON according to Table 1 below, the oscillation structure 102a becomes an oscillation structure where N=1, P=0, S=0, F=1, and R=0. When the control unit 108a is turned ON, the control unit 108b is turned OFF, and the control unit 108c is turned ON, the oscillation structure 102a becomes an oscillation structure where N=2, P=2, S=0, F=2, and R=0. When the control unit 108a is turned OFF, the control unit 108b is turned ON, and the control unit 108c is turned OFF, the oscillation structure 102a becomes an oscillation structure where N=2, P=0, S=2, F=2, and R=0. When a bias is supplied to the oscillation structure 102a in the reverse direction, the values ​​of F and R are interchanged in each oscillation structure, and the values ​​of N, P, and S are the same.

[0064] The oscillator 100 according to the fourth embodiment can transmit or receive electromagnetic waves of three different oscillation frequencies using only one oscillation structure. a =80 [fF], capacitance C of the semiconductor elements 105a to 105b d= 15 [fF]. In addition, the oscillation frequency when a forward bias is supplied by one of the semiconductor elements 105a and 105b that constitute the oscillation structure is set to 500 [GHz]. If the three oscillation frequencies are f1, f2, and f3, respectively, then f1 = 500 [GHz], f2 = 465 [GHz], and f3 = 521 [GHz]. In the equivalent circuit shown in FIG. 14, the correspondence between the operations of the control units 108a to 108c and the oscillation frequencies f1, f2, and f3 is shown in Table 1. [Table 1]

[0065] Example 5 Next, an oscillation element according to Example 5 will be described with reference to FIGS. 15 and 16. FIG. 15 is a top view schematically illustrating an example of the oscillation element according to Example 5, and FIG. 16 is a cross-sectional view taken along line II' in FIG. 15. In an oscillation element 100 according to this example, an oscillation structure 102a includes an antenna 104a and semiconductor elements 105a to 105d. The antenna 104a and the semiconductor elements 105a to 105d are electrically connected to each other, and the semiconductor elements 105a to 105d are electrically connected in parallel to each other via the antenna 104a. The oscillation structure 102b includes an antenna 104b and semiconductor elements 105e to 105l, and the antenna 104b and the semiconductor elements 105e to 105l are electrically connected to each other. The semiconductor elements 105e, 105f, and 105g are electrically connected in series to each other via the conductors 113d and 113e. Semiconductor elements 105h, 105i, and 105j are electrically connected in series with each other via conductors 113f and 113g. Semiconductor elements 105k and 105l are electrically connected in series with each other via conductor 113h. Semiconductor elements 105e to 105g, semiconductor elements 105h to 105j, and semiconductor elements 105k to 105l are electrically connected in parallel with each other via antenna 104b. Oscillation structure 102c has antenna 104c and semiconductor elements 105m to 105p, and antenna 104c and semiconductor elements 105m to 105p are electrically connected to each other. Semiconductor elements 105m and 105n are electrically connected in series with each other via conductor 113i, and semiconductor elements 105o and 105p are electrically connected in series with each other via conductor 113j. The semiconductor elements 105m to 105n and the semiconductor elements 105o to 105p are electrically connected in parallel to each other via the antenna 104c.

[0066] In substrate low-resistance layer 115, the connection portions with semiconductor elements 105e, 105f, 105h, 105i, 105k, 105m, and 105o are not connected to any of pads 112a-d. Power supply structure 103 has power sources 106a and 106b and bias supply unit 107, and bias supply unit 107 has wiring 111 including wire bonding, pads 112a-112d, and conductors 113a-113j.

[0067] The oscillator 100 according to the fifth embodiment can simultaneously transmit or receive electromagnetic waves of three different oscillation frequencies. In this embodiment, the semiconductor elements 105a to 105p have negative resistance characteristics only in the range of 0.6 V to 1.3 V when a forward bias is applied. The cross-sectional areas of the semiconductor elements 105e and 105f, as well as the semiconductor elements 105h and 105i, included in the oscillator structure 102b, are adjusted so that they are driven in a positive resistance region.

[0068] In a plan view of the oscillation element 100, the cross-sectional areas of the semiconductor elements 105a to 105p in a plane parallel to the substrate 101 (a plane parallel to the paper surface) are denoted as Aa to Ap, respectively. However, Aa to Ap are uniform in the thickness direction. First, in the oscillation structure 102b, Ae=Af=2Ag, Ah=Ai=2Aj, and Ak=Al are satisfied, and in the oscillation structure 102c, Am=An and Ao=Ap are satisfied. In this case, when the voltage of the power supply 106b is set to 2 [V], in the oscillation structures 102b and 102c, the semiconductor elements 105g, 105j, and 10 Only the semiconductor elements 105k, 105l, 105m, 105n, 105o, and 105p can be driven in a negative resistance region of 1 V. When the voltage of the power supply 106a is set to 1 V, the semiconductor elements 105a to 105d can also be driven in a negative resistance region of 1 V. Furthermore, in the oscillator element 100 of this embodiment, Aa=Ab=Ac=Ad=Ag=Aj=Ak=Al=Am=An=Ao=Ap are satisfied.

[0069] In the oscillation element 100 of the fifth embodiment, S1 to S n It consists of semiconductor elements, where S k(k=1 to n) satisfies the following formula (15).

number

[0070] And S k Each semiconductor element is composed of a single semiconductor element or single semiconductor elements connected in series with each other, and has a negative resistance characteristic when driven by the power supply structure 103. Furthermore, the oscillation element 100 of Example 5 satisfies at least one of the following conditions (1) to (5). (1) N varies between different oscillation structures (2) n is different between different oscillation structures (3) S1 to S of one oscillation structure n At least one of these is a value that does not exist in the other oscillation structure. (4) F varies between different oscillation structures (5) R varies between different oscillator structures

[0071] 15, a bias is supplied to the oscillation structures 102a to 102c in the forward direction. Furthermore, the case where N=4, S1=1, S2=1, S3=1, S4=1, P=4, F=4, and R=0 corresponds to the oscillation structure 102a. Furthermore, the case where N=4, S1=1, S2=1, S3=2, P=3, F=4, and R=0 corresponds to the oscillation structure 102b. Furthermore, the case where N=4, S1=2, S2=2, P=2, F=4, and R=0 corresponds to the oscillation structure 102c. Note that when a bias is supplied to the oscillation structures 102a to 102c in the reverse direction, the values ​​of F and R are swapped in each oscillation structure, and N, S k , the value of P will be the same.

[0072] In the oscillation element 100 according to the fifth embodiment, the capacitance C a =80 [fF], capacitance C of semiconductor elements 105a to 105d, 105g, 105j, 105k to 105p d= 15 [fF]. In addition, the oscillation frequency when a forward bias is supplied by any one of the semiconductor elements 105a to 105d, 105g, 105j, and 105k to 105p that constitute the oscillation structure is set to 500 [GHz]. If the oscillation frequencies of the oscillation structure 102a, the oscillation structure 102b, and the oscillation structure 102c are f1, f2, and f3, respectively, then f1 = 412 [GHz], f2 = 450 [GHz], and f3 = 500 [GHz].

[0073] Example 6 Next, an oscillation element according to Example 6 will be described with reference to FIGS. 17 to 19. FIG. 17 is a top view schematically showing an example of an oscillation element according to Example 6, and FIG. 18 is a cross-sectional view taken along line J-J' in FIG. 17. FIG. 19 is an equivalent circuit of the oscillation element according to Example 6, and for simplicity, only semiconductor elements 105a to 105d are focused on. In the oscillation element according to this example, the oscillation structure 102a has an antenna 104a and semiconductor elements 105a to 105d, and the antenna 104a and semiconductor element 105a are electrically connected to each other. The conductor 113b is electrically connected to the semiconductor element 105b, the conductor 113c is electrically connected to the semiconductor element 105c, and the conductor 113d is electrically connected to the semiconductor element 105d. Pad 112e Pads 112a to 112h are electrically connected to substrate low-resistance layer 115, pad 112e is electrically connected to semiconductor element 105a via substrate low-resistance layer 115, and pad 112f is electrically connected to semiconductor element 105b via substrate low-resistance layer 115. Pad 112g is electrically connected to semiconductor element 105c via substrate low-resistance layer 115, and pad 112h is electrically connected to semiconductor element 105d and first insulator 109 via substrate low-resistance layer 115. Power supply structure 103 has power source 106, bias supply unit 107, and control units 108a to 108f, and bias supply unit 107 has wiring 111 including wire bonding, pads 112a to 112h, and conductors 113a to 113d. When control units 108a, 108b, 108d, and 108e are turned ON and control units 108c and 108f are turned OFF, semiconductor elements 105a to 105d are electrically connected in parallel to one another. When control units 108a, 108d, and 108f are turned ON and control units 108b, 108c, and 108e are turned OFF, semiconductor elements 105a, semiconductor element 105b, and semiconductor elements 105c to 105d are electrically connected in parallel to one another. When control units 108c and 108f are turned ON and control units 108a, 108b, 108d, and 108e are turned OFF, semiconductor elements 105a to 105b and semiconductor elements 105c to 105d are electrically connected in parallel to one another.

[0074] The oscillator 100 of the sixth embodiment is made up of S1 to S5 connected in parallel to each other. n As in Example 5, it is composed of S k (k=1 to n) satisfies equation (15). k The (k=1 to n) semiconductor elements are composed of a single semiconductor element or single semiconductor elements connected in series with each other, and have negative resistance characteristics when driven by the power supply structure 103. Furthermore, the oscillation element 100 of Example 6 satisfies at least one of the following conditions (1) to (5). (1) N changes depending on the operation of the control unit (2) n changes depending on the operation of the control unit (3) The control unit operates to change n to n', and S1 to S n’ At least one of S1 to S nis a value that does not exist in (4) F changes depending on the operation of the control unit (5) R changes depending on the operation of the control unit

[0075] 17, a bias is supplied to the oscillation structure 102a in the forward direction. Then, according to Table 2 below, the control unit 108a is turned OFF, the control unit 108b is turned OFF, the control unit 108c is turned ON, the control unit 108d is turned OFF, the control unit 108e is turned ON, and the control unit 108f is turned OFF. At this time, the oscillation structure 102a becomes an oscillation structure where N=4, S1=1, S2=1, S3=1, S4=1, P=4, F=4, and R=0. Also, the control unit 108a is turned OFF, the control unit 108b is turned ON, the control unit 108c is turned ON, the control unit 108d is turned OFF, the control unit 108e is turned OFF, and the control unit 108f is turned ON. At this time, the oscillation structure 102a becomes an oscillation structure where N=4, S1=1, S2=1, S3=2, P=3, F=4, and R=0. Also, control unit 108a is ON, control unit 108b is ON, control unit 108c is OFF, control unit 108d is ON, control unit 108e is OFF, and control unit 108f is ON. At this time, oscillation structure 102a becomes an oscillation structure where N=4, S1=2, S2=2, P=2, F=4, and R=0. Note that when a bias is supplied to oscillation structure 102a in the reverse direction, the values ​​of F and R are swapped in each oscillation structure, and N, S k , the value of P will be the same.

[0076] The oscillator 100 according to the sixth embodiment is capable of transmitting or receiving electromagnetic waves of three different oscillation frequencies with only one oscillation structure. a =80 [fF], capacitance C of semiconductor elements 105a to 105d d = 15 [fF], and the oscillation frequency of any one of the semiconductor elements 105a to 105d that make up the oscillation structure 102a is 500 [GHz]. If the three oscillation frequencies are f1, f2, and f3, respectively, then f1 = 412 [GHz], f2 = 450 [GHz], and f3 = 500 [GHz]. From the equivalent circuit shown in FIG. 19, the correspondence between the operations of the control units 108a to 108f and the oscillation frequencies f1, f2, and f3 is shown in Table 2. This is shown. [Table 2]

[0077] Example 7 Next, an oscillation device according to Example 7 will be described with reference to FIGS. 20 and 21. FIG. 20 is a top view schematically illustrating an example of the oscillation device according to Example 7, and FIG. 21 is a cross-sectional view taken along line K-K' in FIG. 20. In the oscillation device according to this example, an oscillation structure 102a includes an antenna 104a and semiconductor elements 105a to 105d. The antenna 104a and the semiconductor elements 105a to 105d are electrically connected to each other, and the semiconductor elements 105a to 105d are electrically connected in series to each other via conductors 113d to 113f. The oscillation structure 102b includes an antenna 104b and semiconductor elements 105e to 105h. The antenna 104b and the semiconductor elements 105e to 105h are electrically connected to each other, and the semiconductor elements 105e and 105f are electrically connected in series to each other via conductor 113g. The semiconductor element 105g and the semiconductor element 105h are electrically connected in parallel to each other via the conductor 113h. The semiconductor element 105f and the semiconductor elements 105g to 105h are electrically connected in series to each other via the conductor 113h. The oscillation structure 102c has an antenna 104c and the semiconductor elements 105i to 105l. The antenna 104c and the semiconductor elements 105i to 105l are electrically connected to each other, and the semiconductor element 105i and the semiconductor element 105j are electrically connected in parallel to each other via the antenna 104c. The semiconductor element 105k and the semiconductor element 105l are electrically connected in parallel to each other via the conductor 113i. The semiconductor elements 105i to 105j and the semiconductor elements 105k to 105l are electrically connected in series to each other via the conductor 113i. In substrate low-resistance layer 115, the connection portions with semiconductor elements 105a, 105b, 105c, 105e, 105f, 105i, and 105j are not connected to any of pads 112a to 112d. Power supply structure 103 has power sources 106a, 106b, and 106c, and bias supply unit 107, and bias supply unit 107 has wiring 111 including wire bonding, pads 112a to 112d, and conductors 113a to 113i.

[0078] The oscillator 100 according to the seventh embodiment is capable of simultaneously transmitting or receiving electromagnetic waves of three different oscillation frequencies. In this embodiment, the semiconductor elements 105a to 105l exhibit negative resistance characteristics only in the range of 0.6 V to 1.3 V when a forward bias is applied. The cross-sectional areas of the semiconductor elements 105a to 105l are designated Aa to Al, respectively. Note that Aa to Al are uniform in the thickness direction. In the oscillator structure 102a, Aa=Ab=Ac=Ad are satisfied. In this case, if the voltage of the power supply 106a is set to 4 V, the semiconductor elements 105a to 105d can be driven in a negative resistance region of 1 V. In the oscillator structure 102b, Ae=Af=2Ag=2Ah are satisfied. In this case, if the voltage of the power supply 106b is set to 3 V, the semiconductor elements 105e to 105h can be driven in a negative resistance region of 1 V. In the oscillation structure 102c, Ai=Aj=Ak=Al is satisfied. In this case, if the voltage of the power supply 106c is set to 2 [V], the semiconductor elements 105i to 105l can be driven in the negative resistance region of 1 [V]. In this embodiment, further, Aa=Ab=Ac=Ad=Ag=Ah =Ai=Aj=Ak=Al.

[0079] The oscillation element 100 of the seventh embodiment has P1 to P m It consists of semiconductor elements, where P l (l=1 to m) satisfies the following equation (16).

number

[0080] And P l Each semiconductor element is composed of a single semiconductor element or single semiconductor elements connected in parallel to each other, and has a negative resistance characteristic when driven by the power supply structure 103. Furthermore, the oscillation element 100 of Example 7 satisfies at least one of the following conditions (1) to (5). (1) N varies between different oscillation structures (2) m is different between different oscillation structures (3) P1 to P of one oscillation structure m At least one of these is a value that does not exist in the other oscillation structure. (4) F varies between different oscillation structures (5) R varies between different oscillator structures

[0081] 20, a bias is supplied to the oscillation structures 102a to 102c in the forward direction. Furthermore, the case where N=4, S=4, P1=1, P2=1, P3=1, P4=1, F=4, and R=0 corresponds to the oscillation structure 102a. Furthermore, the case where N=4, S=3, P1=1, P2=1, P3=2, F=4, and R=0 corresponds to the oscillation structure 102b. Furthermore, the case where N=4, S=2, P1=2, P2=2, F=4, and R=0 corresponds to the oscillation structure 102c. Note that when a bias is supplied to the oscillation structures 102a to 102c in the reverse direction, the values ​​of F and R are swapped in each oscillation structure, and N, S, and P l The value of is the same.

[0082] In the oscillation element 100 according to the seventh embodiment, the capacitance C a =80 [fF], capacitance C of semiconductor elements 105a to 105d and 105g to 105l d = 15 [fF]. Furthermore, when the semiconductor elements constituting the oscillation structures 102a to 102c are any one of 105a to 105f and 105i to 105l, the oscillation frequency is 500 [GHz]. If the oscillation frequencies of the oscillation structures 102a, 102b, and 102c are f1, f2, and f3, respectively, then f1 = 533 [GHz], f2 = 514 [GHz], and f3 = 500 [GHz].

[0083] Example 8 Next, an oscillation device according to Example 8 will be described with reference to FIGS. 22 to 24. FIG. 22 is a top view schematically illustrating an example of the oscillation device according to Example 8, and FIG. 23 is a cross-sectional view taken along line L-L' in FIG. 22. FIG. 24 is an equivalent circuit of the oscillation device according to Example 8, and for simplicity, focuses only on the semiconductor device 105. In the oscillation device according to this example, the oscillation structure 102a has an antenna 104a and semiconductor devices 105a to 105d, and the antenna 104a and the semiconductor device 105a are electrically connected to each other. The conductor 113b is electrically connected to the semiconductor device 105b, the semiconductor device 105b and the semiconductor device 105c are electrically connected in series via the conductor 113c, and the conductor 113d is electrically connected to the semiconductor device 105d. The pads 112e to 112h are electrically connected to the substrate low resistance layer 115, the pad 112e is electrically connected to the semiconductor element 105a through the substrate low resistance layer 115, and the pad 112f is electrically connected to the semiconductor element 105b through the substrate low resistance layer 115. The pad 112g is electrically connected to the semiconductor element 105c through the substrate low resistance layer 115, and the pad 112h is electrically connected to semiconductor element 105d and first insulator 109 via substrate low-resistance layer 115. Power supply structure 103 includes power source 106, bias supply unit 107, and control units 108a-108f. Bias supply unit 107 includes wiring 111 including wire bonding, pads 112a-112h, and conductors 113a-113d. When control units 108c and 108e are turned ON and control units 108a, 108b, 108d, and 108f are turned OFF, semiconductor elements 105a-105d are electrically connected in series with each other. When control units 108b, 108c, and 108f are turned ON and control units 108a, 108d, and 108e are turned OFF, semiconductor element 105a, semiconductor element 105b, and semiconductor elements 105c-105d are electrically connected in series with each other. When control units 108a, 108b, 108d, and 108f are turned ON and control units 108c and 108e are turned OFF, semiconductor elements 105a to 105b and semiconductor elements 105c to 105d are electrically connected in series with each other.

[0084] The oscillation element 100 of Example 8 has P1 to P mAs in Example 7, the semiconductor element P l (l=1 to m) satisfies equation (16). l Each semiconductor element is composed of a single semiconductor element or single semiconductor elements connected in parallel to each other, and has a negative resistance characteristic when driven by the power supply structure 103. Furthermore, the oscillation element 100 of Example 8 satisfies at least one of the following conditions (1) to (5). (1) N changes depending on the operation of the control unit (2) m changes depending on the operation of the control unit (3) The control unit changes m to m', and P1 to P m’ At least one of the values ​​does not exist in S1 to Sm. (4) F changes depending on the operation of the control unit (5) R changes depending on the operation of the control unit

[0085] 22, a bias is supplied to the oscillation structure 102a in the forward direction. Then, according to Table 3 below, the control unit 108a is turned OFF, the control unit 108b is turned OFF, the control unit 108c is turned ON, the control unit 108d is turned OFF, the control unit 108e is turned ON, and the control unit 108f is turned OFF. At this time, the oscillation structure 102a becomes an oscillation structure where N=4, S=4, P1=1, P2=1, P3=1, P4=1, F=4, and R=0. Also, the control unit 108a is turned OFF, the control unit 108b is turned ON, the control unit 108c is turned ON, the control unit 108d is turned OFF, the control unit 108e is turned OFF, and the control unit 108f is turned ON. At this time, the oscillation structure 102a becomes an oscillation structure where N=4, S=3, P1=1, P2=1, P3=2, F=4, and R=0. Also, control unit 108a is ON, control unit 108b is ON, control unit 108c is OFF, control unit 108d is ON, control unit 108e is OFF, and control unit 108f is ON. At this time, oscillation structure 102a becomes an oscillation structure where N=4, S=2, P1=2, P2=2, F=4, and R=0. Note that when a bias is supplied to oscillation structure 102a in the reverse direction, the values ​​of F and R are swapped in each oscillation structure, and N, S, and P l The value of is the same.

[0086] The oscillator 100 according to the eighth embodiment can transmit or receive electromagnetic waves of three different oscillation frequencies using only one oscillation structure. a =80 [fF], capacitance C of semiconductor elements 105a to 105d d = 15 [fF]. In addition, the oscillation frequency when a forward bias is supplied by any one of the semiconductor elements 105a to 105d that constitute the oscillation structure is set to 500 [GHz]. If the three oscillation frequencies are f1, f2, and f3, respectively, then f1 = 533 [GHz], f2 = 526 [GHz], and f3 = 500 [GHz]. From the equivalent circuit shown in FIG. 24, the correspondence between the operation of the control units 108a to 108f and the oscillation frequencies f1, f2, and f3 is shown in Table 3. [Table 3]

[0087] The above is a description of the present embodiment, but the configuration and processing of the above oscillator are not limited to the above examples and can be modified in various ways within the scope of the technical concept of the present invention. For example, in the above-described embodiments and examples, a square patch antenna is used as the terahertz wave resonator. However, the shape of the resonator is not limited to this. For example, resonators with structures using patch conductors in polygonal shapes such as rectangles and triangles, circles, ellipses, etc. may also be used. In addition, the material of the RTD can be changed as appropriate.

[0088] Furthermore, the oscillator described in the above embodiments and examples can be applied to, for example, a detection system. The detection system includes a receiving element that receives high-frequency waves from the oscillator and a processing circuit that processes the signals received by the receiving element. The detection system may be, for example, a camera system using terahertz waves.

[0089] A camera system as an application example will be described below with reference to FIG. 27. Terahertz camera system 1000 has transmitter 1001 that emits terahertz waves using the oscillator described in the above embodiments and examples, and receiver 1002 that detects the terahertz waves. Terahertz camera system 1000 also has controller 1003 that controls the operation of transmitter 1001 and receiver 1002 based on an external signal. Controller 1003 has a processing circuit that processes the signal received by receiver 1002, and processes an image based on the detected terahertz waves or outputs it to the outside. The oscillator of each embodiment may be used in transmitter 1001 or receiver 1002.

[0090] Terahertz waves from the transmitter 1001 are reflected by the subject 1005 and detected by the receiver 1002. A camera system having such a transmitter 1001 and receiver 1002 is also called an active camera system. Note that in a passive camera system without the transmitter 1001, the oscillator element of each embodiment can be used in the receiver. By using the electromagnetic wave module of each embodiment, the electromagnetic wave camera system can achieve high detection sensitivity and obtain high-quality images. [Explanation of symbols]

[0091] 101 substrate, 102a to 102c oscillation structures, 103 power supply structure, 105a to 105p Semiconductor element, 107 bias supply unit

Claims

1. A substrate; a plurality of oscillation structures provided on the substrate for transmitting or receiving electromagnetic waves; and a power supply structure for electrically driving the plurality of oscillation structures. and the power supply structure includes a power source and a bias supply unit that supplies a bias to the plurality of oscillation structures; the oscillation structure includes an antenna and N (N≧1) semiconductor elements electrically connected to the antenna; the semiconductor elements have negative resistance characteristics when driven by the power supply structure, and P (P≧0) of the N elements are connected in parallel with each other, S (S≧0) are connected in series with each other, and when the direction of current flowing vertically upward with respect to the substrate is defined as the forward direction, F (F≧0) elements are supplied with a bias in the forward direction, and R (R≧0) elements are supplied with a bias in the reverse direction, the semiconductor element of at least one of the oscillation structures has current-voltage characteristics that are asymmetrical with respect to a forward bias and a reverse bias, At least one of N, P, S, F, and R is different between the different oscillation structures. An oscillation element characterized by:

2. A substrate; a plurality of oscillation structures provided on the substrate for transmitting or receiving electromagnetic waves; and a power supply structure for electrically driving the plurality of oscillation structures. and the power supply structure includes a power source, a bias supply unit that supplies a bias to the plurality of oscillation structures, and a control unit that controls the supply of the bias by the bias supply unit; the oscillation structure includes an antenna and N (N≧1) semiconductor elements electrically connected to the antenna; N of the N transistors are supplied with a bias by the operation of the control unit and have negative resistance characteristics, and of the N transistors, P (P≧0) of the N transistors are supplied with a bias by the operation of the control unit and are connected in parallel with each other, and S (S≧0) are supplied with a bias by the operation of the control unit, and are connected in series with each other, and when the direction of a current flowing vertically upward with respect to the substrate is taken as a forward direction, F (F≧0) are supplied with a bias in the forward direction by the operation of the control unit, and R (R≧0) are supplied with a bias in the reverse direction by the operation of the control unit, the semiconductor element of at least one of the oscillation structures has current-voltage characteristics that are asymmetrical with respect to a forward bias and a reverse bias, At least one of N, P, S, F, and R is different between the different oscillation structures by the operation of the control unit. An oscillation element characterized by:

3. A substrate; an oscillation structure provided on the substrate for transmitting or receiving electromagnetic waves, and a power supply structure for electrically driving the oscillation structure; and the power supply structure includes a power source, a bias supply unit that supplies a bias to the oscillation structure, and a control unit that controls the supply of the bias by the bias supply unit; the oscillation structure includes an antenna and N (N≧2) semiconductor elements electrically connected to the antenna; N of the N transistors are supplied with a bias by the operation of the control unit and have negative resistance characteristics, and among the N transistors, P (P≧0) of the N transistors are supplied with a bias by the operation of the control unit and are mutually are connected in parallel, S (S≧0) of which are supplied with a bias by the operation of the control unit, and are connected in series with each other, and when the direction of a current flowing vertically upward with respect to the substrate is taken as the forward direction, F (F≧0) of which are supplied with a bias in the forward direction by the operation of the control unit, and R (R≧0) of which are supplied with a bias in the reverse direction by the operation of the control unit, the semiconductor element has current-voltage characteristics that are asymmetrical between a forward bias and a reverse bias, At least one of N, P, S, F, and R changes due to the operation of the control unit. An oscillation element characterized by:

4. The N is N≧2, S connected in parallel to each other １ Piece ~ S ｎ The semiconductor element is composed of S ｋ (k=1 to n) satisfies the following formula (1): [Equation 1] The S ｋ the (k=1 to n) semiconductor elements are composed of individual semiconductor elements or individual semiconductor elements connected in series to each other, and have negative resistance characteristics when driven by the power supply structure; At least one of the following conditions (1) to (5) is satisfied: (1) The N is different between different oscillation structures. (2) The n is different between different oscillation structures. (3) The S of one oscillation structure １ ~S ｎ At least one of the values ​​does not exist in the other oscillation structure. (4) The F is different between different oscillation structures. (5) The R is different between different oscillation structures.

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

5. The N is N≧2, S connected in parallel to each other １ Piece ~ S ｎ The semiconductor element is composed of S ｋ (k=1 to n) satisfies the following formula (2): [Equation 2] The S ｋ the (k=1 to n) semiconductor elements are composed of individual semiconductor elements or individual semiconductor elements connected in series to each other, and have negative resistance characteristics when driven by the power supply structure; At least one of the following conditions (1) to (5) is satisfied: (1) The N changes depending on the operation of the control unit. (2) The n changes depending on the operation of the control unit. (3) The n changes to n' by the operation of the control unit, and the S １ ~S ｎ’ At least one of the S １ ~S ｎ is a value that does not exist in (4) The F changes depending on the operation of the control unit. (5) The R changes depending on the operation of the control unit.

4. The oscillator according to claim 2, wherein the first and second electrodes are electrically connected to each other.

6. The N is N≧2, P connected in series with each other １ P to Pm of the semiconductor elements, ｌ (l=1 to m) satisfies the following formula (3): [Equation 3] The P ｌ the (l=1 to m) semiconductor elements are composed of individual semiconductor elements or individual semiconductor elements connected in parallel to each other, and have negative resistance characteristics when driven by the power supply structure; At least one of the following conditions (1) to (5) is satisfied: (1) The N is different between different oscillation structures. (2) The m is different between different oscillation structures. (3) The P of one oscillation structure １ ~P ｍ At least one of the values ​​does not exist in the other oscillation structure. (4) The F is different between different oscillation structures. (5) The R is different between different oscillation structures.

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

7. The N is N≧2, P connected in series with each other １ Pieces ~ P ｍ The semiconductor element is composed of P ｌ (l=1 to m) satisfies the following formula (4): [Equation 4] The P ｌ The (l=1 to m) semiconductor elements are composed of individual semiconductor elements or individual semiconductor elements connected in parallel to each other, and have negative resistance characteristics when driven by the power supply structure, At least one of the following conditions (1) to (5) is satisfied: (1) The N changes depending on the operation of the control unit. (2) The m changes depending on the operation of the control unit. (3) The m changes to m' by the operation of the control unit, and the P １ ~P ｍ’ At least one of the P １ ~P ｍ is a value that does not exist in (4) The F changes depending on the operation of the control unit. (5) The R changes depending on the operation of the control unit.

4. The oscillator according to claim 2, wherein the first and second electrodes are electrically connected to each other.

8. The semiconductor element has a driving voltage V ｍｉｎ From V ｍａｘ Range (V ｍｉｎ >0 and V ｍａｘ >0) and the driving voltage −V when the bias is supplied in the reverse direction ｍｉｎ’ From -V ｍａｘ’ (V ｍｉｎ’ <0 and V ｍａｘ’ <0), The S ｋ The semiconductor elements are C ｋ pieces (C ｋ ≧0) semiconductor elements, Said C ｋ The semiconductor elements are C ｋ ≧2, and is composed of single semiconductor elements connected in series with each other, ｋ the semiconductor element has a positive resistance characteristic when driven by the power supply structure, The S ｋ The semiconductor elements (k=1 to n) are single semiconductor elements or semiconductor elements E connected in series with each other. ｉｋ (i = 1 to S ｋ ) and the semiconductor element E ｉｋ The above The cross-sectional area of ​​the cross section parallel to the substrate is A ｉｋ Then, for any k and any i, i', (i≠i', 1≦i, i'≦S ｋ ), satisfying the following formula (5): Said C ｋ The semiconductor elements (k=1 to n) are single semiconductor elements or semiconductor elements F connected in series with each other. ｉｋ (i = 1 to C ｋ ) and the semiconductor element F ｉｋ The cross-sectional area of ​​the cross section parallel to the substrate is B ｉｋ Then, for any k, k' (k≠k', 1≦k, k'≦n), ｋ The voltage V applied to the semiconductor elements (k=1 to n) ｉｎ and V ｍｉｎ , V ｍａｘ and V ｍｉｎ’ , V ｍａｘ’ satisfies the following formulas (6) to (9): [Equation 5] [Equation 6] [Equation 7] [Equation 8] [Equation 9] 6. The oscillator according to claim 4, wherein the first and second electrodes are electrically connected to each other.

9. The semiconductor element has a driving voltage V ｍｉｎ From V ｍａｘ Range (V ｍｉｎ >0 and V ｍａｘ >0) and the driving voltage −V when the bias is supplied in the reverse direction ｍｉｎ’ From -V ｍａｘ’ (V ｍｉｎ’ <0 and V ｍａｘ’ <0), The P ｌ The semiconductor elements (l=1 to m) are single semiconductor elements or semiconductor elements E connected in parallel to each other. ｊｌ (j = 1 to P ｌ ) and the semiconductor element E ｊｌ The cross-sectional area of ​​the cross section parallel to the substrate is A ｊｌ When this is the case, for any l, l', and j (j=1 to Pl) (l≠l', 1≦l, l'≦m), the cross-sectional area A of the semiconductor element ｊｌ and A ｊｌ’ , the P ｍ The voltage V applied to the semiconductor elements ｉｎ and V ｍｉｎ , V ｍａｘ and V ｍｉｎ’ , V ｍａｘ’ satisfies the following formulas (10) and (11): [Equation 10] [0011] 8. The oscillator according to claim 6, wherein the first and second electrodes are electrically connected to each other.

10. 10. The oscillation element according to claim 1, wherein the power supply structure drives a plurality of the oscillation structures simultaneously.

11. 8. The oscillation element according to claim 2, wherein the control unit operates to individually drive the plurality of oscillation structures in the power supply structure.

12. The oscillation element according to any one of claims 2, 5, 7 and 11, characterized in that in the power supply structure, the control unit can select between individual driving of the plurality of oscillation structures and simultaneous driving of the plurality of oscillation structures.

13. 13. The oscillation element according to claim 2, wherein in the power supply structure, a part of the bias supply unit is insulated by the operation of the control unit.

14. 14. The oscillation element according to claim 2, wherein in the power supply structure, a power source connected to the semiconductor element or the oscillation structure is switched by operation of the control unit.

15. 15. The oscillation element according to claim 1, wherein the antenna is a patch antenna.

16. 16. The oscillator element according to claim 1, wherein the electromagnetic wave contains frequency components in the range of 30 GHz to 30 THz.

17. 17. The oscillation element according to claim 1, wherein the semiconductor element is a resonant tunneling diode.

18. The oscillation element according to any one of claims 1 to 17, a receiving element that receives a high frequency wave from the oscillation element; a processing circuit for processing signals from the receiving elements; A detection system comprising:

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