CN101656523B - Three-dimensional Structure TE011-λ/4-π Mode Resonator - Google Patents

Abstract

The invention discloses a three-dimensional structure TE ₀₁₁ -λ/4-π mode resonator. The two output ends of each active circuit are connected to the two open-circuit ends of the corresponding λ/4 resonator at the junction of the silicon substrate layer and the packaging layer, and the two short-circuit ends of each λ/4 resonator are connected to the TE ₀₁₁ The cylindrical waveguide resonator is connected on the first conductive metal plate, the energy coupling is realized through the λ/4 resonator on the first conductive metal plate and the coupling slot of the cylindrical waveguide, the rectangular waveguide is assembled on the second conductive metal plate, through the second The rectangular waveguide on the conductive metal plate and the coupling slot of the cylindrical waveguide realize energy coupling and output energy. The invention is suitable for the power synthesis of silicon-based terahertz sources at the packaging level, the passive circuit is separated from the active circuit, the quality factor of the resonator is high, and the cost can be significantly reduced in large-scale production. Has application value.

Description

Three-dimensional Structure TE011-λ/4-π Mode Resonator

technical field

The invention relates to a terahertz integrated circuit, in particular to a three-dimensional structure TE ₀₁₁ -λ/4-π mode resonator.

Background technique

At present, the international research on terahertz has reached a consensus that terahertz is a radiation source with many unique advantages. It is a scientific and technological field that the international academic circles, industrial circles and governments of various countries attach great importance to and pay attention to. The generation of terahertz waves is a basic and key issue of terahertz technology. In recent years, the generation of terahertz oscillations based on existing integrated circuit technology has also attracted more and more attention from researchers in recent years.

From the perspective of application requirements, silicon-based low-power terahertz sources have great application potential. On the one hand, the silicon-based standard integrated circuit process can achieve mass production and significantly reduce the cost of the application system; on the other hand, it is possible to integrate the oscillation source with other functional circuits of the system also based on silicon technology. These two outstanding advantages make silicon-based low-power terahertz sources very promising in personal wireless communication and low-power terahertz radar.

However, whether the silicon-based terahertz oscillator can be applied and how to increase the integrated output power is a key issue. While the operating frequency is increasing due to technological progress, the continuous shrinking of the line width means that the current that can be tolerated is getting smaller and smaller, so the power output capability of the oscillator is getting smaller and smaller. Improving the output power of the oscillator can be achieved by increasing the oscillation power of a single tube and combining the power of multiple oscillators.

Contents of the invention

Aiming at the problem of how to combine multiple single-tube terahertz oscillators at the chip level to increase the output power, the purpose of the present invention is to provide a three-dimensional structure TE ₀₁₁ -λ/4-π mode resonator, which can combine the oscillator The output power is increased by one to two orders of magnitude.

The technical solution adopted by the present invention to solve its technical problems:

The resonator includes more than two active circuits on the silicon substrate layer, λ/4 resonators corresponding to the number of active circuits on the packaging layer, a metal cylinder, and a first conductive metal plate working in the TE ₀₁₁ mode , TE ₀₁₁ cylindrical waveguide resonator composed of cylindrical waveguide and second conductive metal plate and rectangular waveguide for power output; two output ends a, b of each active circuit and two open circuits of the corresponding λ/4 resonator The end is connected at the junction of the silicon substrate layer and the packaging layer, and the two short-circuit ends of each λ/4 resonator are connected with the cylindrical waveguide resonator on the first conductive metal plate, through the λ/4 resonator on the first conductive metal plate 4 The resonator and the cylindrical waveguide coupling slot realize energy coupling, the rectangular waveguide is assembled on the second conductive metal plate, and the energy is output from the rectangular waveguide through the rectangular waveguide on the second conductive metal plate and the cylindrical waveguide coupling slot to realize energy coupling .

The beneficial effects that the present invention has are:

The λ/4 resonator in the three-dimensional structure TE ₀₁₁ -λ/4-π mode resonator is made into a three-dimensional structure, which is suitable for realization at the packaging level of the silicon-based process; the differential transmission line and the substrate constituting the λ/4 resonator The surface is vertical, and the power lines and signal lines distributed parallel to the surface of the substrate are orthogonal, and the influence of mutual coupling is small. At the same time, compared with the traditional two-dimensional differential transmission line, the three-dimensional structure differential transmission line is far away from the silicon substrate layer, and the influence of substrate loss is reduced; TE The energy storage (or Q value) of the ₀₁₁ cylindrical waveguide resonator is much higher than that of the λ/4 resonator, so the Q value of the resonator will be much larger than the traditional λ/4 resonator; the resonator can effectively combine multiple The power of the λ/4 resonator is combined to obtain an oscillation output that is an order of magnitude higher than the output power of the traditional λ/4 resonator. The invention is suitable for the power synthesis of silicon-based terahertz sources at the packaging level, the passive circuit is separated from the active circuit, the quality factor of the resonator is high, and the cost can be significantly reduced in large-scale production. Has application value.

Description of drawings

Fig. 1 is a longitudinal sectional view of the TE ₀₁₁ -λ/4-π mode resonator disclosed by the present invention.

FIG. 2 is an implementation of an active circuit based on a pair of inverters on a silicon substrate in the present invention.

FIG. 3 is an implementation of active circuits based on cross-coupled pairs on a silicon substrate in the present invention.

Fig. 4 is a three-dimensional structure diagram of a λ/4 resonator in the present invention.

Fig. 5 is a cross-sectional view cut along A-B in Fig. 1 .

FIG. 6 is a cross-sectional view taken along line C-D of FIG. 1 .

In the figure: 1. Active circuit, 2. λ/4 resonator, 3. Metal cylinder, 4. TE ₀₁₁ cylindrical waveguide resonator, 4a, first conductive metal plate, 4b, cylindrical waveguide, 4c, second conductive metal Plate, 5. Rectangular waveguide, 6. Rectangular waveguide and circular waveguide coupling slot, 7. λ/4 resonator and cylindrical waveguide coupling slot.

Detailed ways

As shown in Fig. 1, Fig. 4, Fig. 5, and Fig. 6, the resonator of the present invention includes more than two active circuits 1 on the silicon substrate layer E, and on the encapsulation layer F, the corresponding number of active circuits 1 λ/4 resonator 2, metal cylinder 3, TE ₀₁₁ cylindrical waveguide resonator 4 composed of first conductive metal plate 4a, cylindrical waveguide 4b and second conductive metal plate 4c working in TE ₀₁₁ mode and used for power output Rectangular waveguide 5; the two output ends a, b of each active circuit 1 are connected to the two open ends of the corresponding λ/4 resonator 2 at the junction of the silicon substrate layer and the packaging layer, and each λ/4 resonant The two short-circuit ends of the device 2 are connected with the cylindrical waveguide resonator 4 on the first conductive metal plate 4a, and the energy coupling is realized through the λ/4 resonator on the first conductive metal plate 4a and the cylindrical waveguide coupling slot 7, and the rectangular waveguide 5 is assembled on the second conductive metal plate 4c, the energy coupling is realized through the rectangular waveguide on the second conductive metal plate 4c and the cylindrical waveguide coupling slot 6, and the energy is output from the rectangular waveguide 5.

As shown in FIG. 2, the active circuit 1 is an inverter pair active circuit.

As shown in FIG. 3 , the active circuit 1 is a cross-coupled active circuit.

The number of one active circuit is determined by the output power, the greater the output power, the more the number.

The working principle of the whole resonator is as follows:

(a) The active circuit 1 on the silicon substrate has a negative resistance characteristic, and provides energy for the corresponding λ/4 resonator 2 in the packaging layer, that is, provides energy for the entire TE011-λ/4-π mode resonator;

(b) One end of the two differential transmission lines of the λ/4 resonator 2 connected to the silicon substrate layer is open, and the end connected to the end face of the TE011 cylindrical waveguide resonator 4 in the packaging layer is realized through the first conductive metal plate 4a Short circuit, the direction of the magnetic force lines at the short-circuit end is perpendicular to the line connecting the two ends of the short-circuit end of the differential transmission line, that is, in the radial direction of the end face of the cylindrical waveguide resonator (the circular face where the first conductive metal plate 4a is located);

(c) The λ/4 resonator and the cylindrical waveguide on the end face (the circular surface where the first conductive metal plate 4a is located) where the TE011 cylindrical waveguide resonator 4 and the λ/4 resonator 2 are connected in the encapsulation layer along the radial direction The coupling slot 7 realizes the coupling between multiple λ/4 resonators 2 and the TE011 cylindrical waveguide resonator 4 through the magnetic force lines, excites the TE011 oscillation mode of the cylindrical waveguide 4b, locks the oscillations of all the λ/4 resonators 2 in phase, and perform power synthesis;

(d) The power of the synthesized oscillating signal is coupled to the rectangular waveguide 5 through the rectangular waveguide and cylindrical waveguide coupling slot 6 on the second conductive metal plate 4c for output.

The following takes the TE011-λ/4-π resonator working at 0.5THz as an example, where the number of active circuits is 2, and specifically describes the implementation of each part.

The active circuit 1 on the silicon substrate can adopt the active circuit scheme of the inverter pair shown in Figure 2, which is easy to start oscillation and has high efficiency, and can also use the cross-coupled pair shown in Figure 3 Active circuit scheme, the characteristic of this circuit is that its nonlinear characteristics can be controlled by changing the bias current.

At the interface between the silicon substrate layer and the packaging layer, two inverter pairs of circuits or two cross-coupled pairs of circuits a and b that provide negative resistance will be connected to the corresponding number of λ/4 resonators on the packaging layer The two ends of 2 are connected, as shown in Figure 1, to realize the function that the negative resistance circuit provides energy for the resonant circuit.

The λ/4 resonator is the abbreviation of the λ/4 differential transmission line resonator. It is composed of a differential transmission line with a length of λ/4 (λ is the wavelength in the medium). One end is open and the other end is short circuited. The implementation method of multiple λ/4 resonators 2 in the packaging layer is shown in FIG. 4 (a side view of the λ/4 resonators observed from the bottom of the resonance system shown in FIG. 1 ). In Fig. 4, two slots are opened in the same direction as the radius of the cylindrical waveguide 4b on the short-circuit surface of the λ/4 resonator 2, and two differential transmission lines are placed on both sides of each slot along the circumference of the cylindrical waveguide 4b. A λ/4 conductor. In actual production and processing, these two conductors can be formed by cylindrical metal vias on the package level, one end of the metal vias is open, and the other end is short-circuited by the first conductive metal plate 4a, as shown in Figure 4, the corresponding horizontal The cross-sectional view is shown in Figure 5. Processing of metal vias is easy to implement in silicon semiconductor processes. For 0.5THz oscillation, if the relative permittivity of the packaging dielectric material ε _r =4, the corresponding λ/4 is 75um, that is, the length of the differential transmission line is 75um, and the radius of the differential transmission line can be 10um.

The direction of the magnetic force lines at the short-circuit end of the differential transmission line is perpendicular to the line connecting the two ends of the short-circuit end of the differential transmission line, that is, in the radial direction of the end face of the TE ₀₁₁ cylindrical waveguide resonator 4 . In order to realize the coupling of the two λ/4 resonators 2 and the cylindrical waveguide 4b, the TE ₀₁₁ mode of the cylindrical waveguide 4b is excited, as shown in Figure 4, the cylindrical waveguide resonator 4 in the packaging layer along the radial direction of the cylindrical waveguide 4b and The first conductive metal plate 4a connected to the λ/4 resonator 2 opens the coupling slot 7 between the λ/4 resonator and the cylindrical waveguide.

The role of the metal cylinder 3 in Fig. 4 is to make the electric field and magnetic field distribution of each λ/4 resonator satisfy the working state of a very pure λ/4 resonator. The rectangular waveguide 5 above the TE ₀₁₁ cylindrical waveguide resonator 4 is used to output the power synthesized in the TE ₀₁₁ resonator 4, and the intersection part of a rectangular wall of the rectangular waveguide 5 and the second conductive plate 4c passes through the open rectangular waveguide and the cylindrical waveguide The coupling slot 6 realizes the energy coupling between the two. The cross-sectional view of the TE ₀₁₁ cylindrical waveguide resonator 4 coupled with the rectangular waveguide 5 is shown in FIG. 6 .

When the cylindrical waveguide works in the TE ₀₁₁ mode, there is only a magnetic field along the radial direction of the cylinder and an electric field along the circumferential direction of the cylinder, so when the transmission power is constant, the heat loss of the tube wall will decrease monotonously, so its loss is lowest.

The energy storage (or Q value) of the TE ₀₁₁ cylindrical waveguide resonator is much higher than that of the λ/4 resonator, so the frequency mainly depends on the resonance frequency of the TE ₀₁₁ cylindrical waveguide resonator. As long as the TE ₀₁₁ cylindrical waveguide resonator works stably, the oscillations of the two λ/4 oscillators can be synchronously locked. Because the cylindrical waveguide resonator works stably in the TE ₀₁₁ mode, the TE ₀₁₁ -λ/4-π resonator ensures that the two λ/4 resonators work synchronously and stably in the λ/4 oscillation mode.

Claims (4)

1. three-dimensional structure TE ₀₁₁-λ/4-π mould resonator is characterized in that: this resonator comprises two the above active circuits (1) on the silica-based lamella (E), goes up and λ/4 resonators (2) of active circuit (1) corresponding number at encapsulated layer (F), and metal cylinder (3) is operated in TE ₀₁₁The TE that comprises first conductive metal sheet (4a), cylindrical waveguide (4b) and second conductive metal sheet (4c) formation of mould ₀₁₁Cylindrical waveguide resonator (4) and be used for the rectangular waveguide (5) of power output, the silica-based lamella (E) with two above active circuit (1) one sides is connected with the encapsulated layer (F) of the λ with active circuit (1) corresponding number/4 resonators (2) one sides; Two output (a of each active circuit (1), b) two open ends with corresponding λ/4 resonators (2) are connected with the encapsulated layer intersection at silica-based lamella, two short-circuit ends of each λ/4 resonators (2) are connected on first conductive metal sheet (4a) with cylindrical waveguide resonator (4), realize the energy coupling by the λ on first conductive metal sheet (4a)/4 resonators and the cylindrical waveguide coupling line of rabbet joint (7), rectangular waveguide (5) is assemblied on second conductive metal sheet (4c), by rectangular waveguide on second conductive metal sheet (4c) and the coupling of the cylindrical waveguide coupling line of rabbet joint (6) realization energy energy is exported from rectangular waveguide (5).

2. a kind of three-dimensional structure TE according to claim 1 ₀₁₁-λ/4-π mould resonator is characterized in that: described active circuit (1) is that inverter is to active circuit.

3. a kind of three-dimensional structure TE according to claim 1 ₀₁₁-λ/4-π mould resonator is characterized in that: described active circuit (1) is that cross-couplings is to active circuit.

4. a kind of three-dimensional structure TE0 according to claim 1 ₁₁-λ/4-π mould resonator is characterized in that: described active circuit (1) number is that power output is decided, and the big more number of power output is many more.

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