CN112117976B - Photoelectric high-power microwave amplification method based on wide-bandgap semiconductor device - Google Patents
Photoelectric high-power microwave amplification method based on wide-bandgap semiconductor device Download PDFInfo
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Abstract
The invention discloses a photoelectric high-power microwave amplification method based on a wide-bandgap semiconductor device, and aims to solve the problems of low output power and low amplification efficiency of the conventional amplification circuit. The technical scheme is that a B type push-pull amplifying circuit based on a wide band gap semiconductor device is constructed by two power supplies, two pulse forming devices, two wide band gap semiconductor devices, two current limiting resistors, a load resistor and a grounding terminal; the two laser pulses and the voltage generated by the two direct current power supplies simultaneously act on 2 wide band gap semiconductor devices in the amplifying circuit; the 2 wide band gap semiconductor devices are excited by photoelectric signals to work as light-operated variable resistors, and the on-resistance of the wide band gap semiconductor devices is linearly changed along with the light intensity of the high-energy pulse cluster laser, so that the output current and the light intensity are changed in a direct proportion, and the photoelectric microwave is amplified. The amplifier circuit has the advantages of simple structure, high working voltage and high microwave output power, not only eliminates unipolar limitation, but also effectively solves the problem of low output power.
Description
Technical Field
The invention relates to the technical field of high-power microwaves, in particular to a photoelectric high-power microwave amplification method based on a wide-bandgap semiconductor device.
Background
In order to deal with the situations that the electromagnetic environment is increasingly complex and new waveforms and new frequency spectrums continuously emerge under the informatization condition, a novel adaptive microwave source with flexibly adjustable parameters needs to be developed urgently. The traditional method for generating high-power microwaves has been developed for more than forty years, and mainly adopts a mode of combining a pulse power device and a relativistic electric vacuum device, so that the problems of fixed output microwave parameters, single frequency point or difficulty in adjustment and the like generally exist. On the one hand, this is because the relativistic vacuum devices usually have a narrow operating frequency range and, with mechanical structures, parameter adjustment is relatively difficult. On the other hand, the electric vacuum device is operated under a vacuum environment, which results in a bulky microwave generating device designed based on the technical route, and also hinders the development trend of miniaturization and compactness of the current microwave generating device.
With the rise of microwave photonics and the development of solid-state high-power microwave devices without electron beams, microwave amplification schemes using wide-bandgap semiconductor devices have received much attention. For a microwave amplifier, a key issue is how to improve its circuit efficiency. In radio frequency and microwave bands, amplifiers are mainly classified into a, B, AB, and the like. If different bias conditions are configured for the active devices, the amplifier can be operated in different states (i.e., a, B, AB, etc.).
The class-a amplifier circuit usually includes a blocking capacitor, cannot amplify periodic pulse signals with different polarities, and can only output with a single polarity, that is, the amplified output signal is either positive or negative during operation. In addition, the class-a circuit contains a dc component, and the corresponding dc power cannot be output through radio frequency radiation and can only be dissipated in the circuit. Even under ideal conditions of resistive load, no power dissipation and matching network losses, the drain efficiency (i.e. the ratio of rf power to dc power delivered to the load, which is typically used to measure the amplification capability of a microwave amplifier) is only 50% at the highest. Therefore, the class a amplifier circuit is generally used for small signal linear amplification in a non-saturation region, and is not suitable for high-power microwave amplification.
The AB push-pull type microwave amplifier is between A class and B class, can be bipolar output, is widely applied to single-ended power amplification, and has higher theoretical drain efficiency than an A class circuit, and the theoretical drain efficiency reaches 78.5 percent. However, class AB is more suitable for the efficiency improvement of point-to-point rf power amplification, and the practical operation efficiency is low under high frequency operating conditions, for example, the practical efficiency is only 20% for X-band microwave signals. The push-pull pair can be formed only by using n-type and p-type transistors simultaneously in the push-pull type microwave amplifier in class AB, and the mobility difference between electrons and holes is large, so that the transconductance of the n-type transistor is one order of magnitude larger than that of the p-type transistor, and therefore larger direct current input power is needed, and the actual amplification efficiency is reduced.
The idea of constructing a photoconductive Microwave Amplifier with a push-pull Amplifier circuit of Class AB type by using a photoconductive switch based on a wide bandgap semiconductor (i.e. a wide bandgap semiconductor device) instead of an electronic component such as a transistor in a conventional Power Amplifier circuit is proposed in the documents "Optoelectronic Class AB Microwave Power Amplifier (Class AB optoelectric Microwave Amplifier), conference Record of Conference of reference Record of the 2006 twin-seven-ten-th International Power Modulator, pages 2006, 146-149", which shows that the wide bandgap semiconductor device can generate a single frequency of 10GHz as shown in fig. 1. The AB type photoelectric microwave amplifier consists of two high-voltage direct-current power supplies (51, 52), two wide-bandgap semiconductor devices (71, 72), a load resistor 93 and a ground terminal 10. The first high voltage dc power supply 51 is an adjustable positive high voltage dc power supply and the second high voltage dc power supply 52 is an adjustable negative high voltage dc power supply, both having the same parameters except polarity. The first wide band gap semiconductor device 71 and the second wide band gap semiconductor device 72 have the same device size and package, and the substrate material and doping thereof are the same, and both are made of lightly doped GaAs material. The first input laser pulse 81 and the second input laser pulse 82 are both triangular pulse sequences with a width of 50ps and an interval of 100ps (i.e. 10 GHz), and the initial time delay has a difference of 50ps. The first high voltage dc power supply 51 is connected to a first wide bandgap semiconductor device 71 via a high voltage tolerant line, the first wide bandgap semiconductor device 71 being excited by a first input laser pulse 81 to form a first shunt; the second high voltage dc power supply 52 is connected to a second wide bandgap semiconductor device 72 by a high voltage tolerant line, the second wide bandgap semiconductor device 72 being excited by a second input laser pulse 82 to form a second shunt. The first and second branches are connected in parallel and then in series with a load resistor 93, the load resistor 93 being connected to the ground terminal 10. The load resistor 93 outputs a desired radio frequency signal.
Compared with the traditional microwave amplification circuit, the AB-type photoelectric microwave amplifier based on the wide-bandgap semiconductor device shown in the figure 1 can eliminate the transistor polarity limitation caused by the traditional electric drive, and can reach the theoretical drain efficiency of 78.5%; under the excitation of laser, a network matched with an input signal and a grid bias circuit are not needed, and the complexity of the circuit is reduced. However, since the thickness of the GaAs substrate reported in the literature is very thin, the allowable bias voltage is limited to a few volts, so the output power is only a few watts, and the requirement of high power output of microwave cannot be met; furthermore, the output signal across the load resistor 93 is significantly distorted and difficult to cancel.
For conventional microwave amplification circuits, when the amplifier operates in class B, the transistor bias causes the active device to be turned on for only half a radio frequency cycle, i.e. 180 °. This class can be implemented by two typical architectures, single-ended and push-pull (using a two-stage single-ended amplifier). Single-ended class B amplifiers have poor linearity, causing output distortion. In the radio frequency and microwave band, the push-pull type amplifying structure in class B is more suitable. In a push-pull type B amplification structure, if a wide band gap semiconductor device is used as an active device, the two wide band gap semiconductor devices share an output load, and each wide band gap semiconductor device is turned on for only a half cycle, so that the amplifier can continuously output power in the cycle as a whole. Under the condition of selecting proper output matching conditions for the wide-bandgap semiconductor device, the amplifying structure can have good linearity, large gain, high output power and high efficiency (the theoretical value can reach 78.5 percent, and the actual value can reach 60 percent). Therefore, the B-type push-pull amplifying circuit based on the wide-bandgap semiconductor device has great prospect in the field of future high-power microwave amplification. However, no technical scheme for realizing high-power microwave amplification by using the technology is disclosed.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a photoelectric high-power microwave amplification method based on a wide-bandgap semiconductor device, so as to solve the problems of low output power and low amplification efficiency existing in the technical scheme of generating microwaves by using the semiconductor device, optimize a circuit structure, effectively reduce electric power loss and realize high output power and high efficiency of a photoelectric microwave amplifier.
In order to achieve the purpose, the technical scheme of the invention is as follows: on the basis of the traditional B-type microwave amplification circuit, a wide-band-gap semiconductor device is used as an active device, and a B-type push-pull amplification circuit based on the wide-band-gap semiconductor device is constructed. Two laser pulse sequences with complementary time are used for triggering the wide-band gap semiconductor device, kV-level bias voltage is applied at the same time, the wide-band gap semiconductor device works in a linear mode (in the linear working mode, a photon enters the wide-band gap semiconductor device, correspondingly, a pair of hole-electron pairs are generated in the device, electrons move under the action of an electric field generated by the applied voltage to form current, the current generated in the mode has the same waveform and frequency with the incident laser, and the frequency is the maximum reciprocal of the recombination time of a semiconductor wafer carrier), and photoelectric microwave amplification is carried out under the excitation of a photoelectric signal. The circuit can output a high frequency, high power electrical signal at the same frequency as the incident laser light. The carrier recombination time of the wide-band-gap semiconductor device is short and is in the order of 1ns, so that the frequency of an output electric signal can reach a GHz frequency band; under the conditions of improving the internal doping of the wide band gap semiconductor and improving the photoelectric conversion efficiency, when the working voltage of a single wide band gap semiconductor device reaches a kV level, the output electric power can reach a MW level.
The specific technical scheme of the invention comprises the following steps:
in the first step, a class B push-pull amplifying circuit based on a wide band gap semiconductor device is constructed, and the class B push-pull amplifying circuit based on the wide band gap semiconductor device is composed of two power supplies (namely, a first power supply and a second power supply), two pulse forming devices (namely, a first pulse forming device and a second pulse forming device), two wide band gap semiconductor devices (namely, a first wide band gap semiconductor device and a second wide band gap semiconductor device), two current limiting resistors, a load resistor, and a ground terminal.
The first power supply is connected with the first pulse forming device through a high-voltage-resistant lead, and the first pulse forming device is connected with the wide anode end of the first wide-bandgap semiconductor device through a high-voltage-resistant lead; the first wide band gap semiconductor device is excited by the first path of input laser pulse, and the cathode end of the first wide band gap semiconductor device is connected with the first current limiting resistor through a high-voltage-resistant wire to form a first branch path.
The second power supply is connected with the second pulse forming device through a high-voltage-resistant lead, and the second pulse forming device is connected with the anode end of the second wide bandgap semiconductor device through a high-voltage-resistant lead; the second wide band gap semiconductor device is excited by the second path of input laser pulse, and the cathode end of the second wide band gap semiconductor device is connected with the second current limiting resistor through a high-voltage-resistant wire to form a second shunt.
The first shunt circuit and the second shunt circuit are connected in parallel and then connected in series with a load resistor, and the load resistor is connected with a ground terminal.
The first power supply and the second power supply are both high-voltage direct-current power supplies, except that the output voltage has opposite polarity, other electrical parameters are the same, and a positive direct-current voltage signal and a negative direct-current voltage signal which have the same amplitude are respectively output. The maximum value of the output voltage is not lower than 20kV and can be tuned. The arrangement is favorable for realizing push-pull amplification and reducing signal distortion.
The first pulse forming device and the second pulse forming device may be the same pulse forming line or the same pulse forming network, and for the first branch or the second branch, the characteristic impedance of the first pulse forming device and the second pulse forming device should be the same as the minimum resistance of the wide bandgap semiconductor device in the branch in which it is located in the on-state under laser irradiation. The first pulse forming device and the second pulse forming device are preferably solid pulse forming lines or solid pulse forming networks, square wave pulses are required to be output, the pulse width is dozens or hundreds of ns, the triggering jitter, the delay jitter and the rise time jitter are all in sub-ns magnitude, the breakdown voltage is higher than 30kV, and the first pulse forming device and the second pulse forming device can be coaxial or flat solid pulse forming lines or solid pulse forming networks.
The first wide band gap semiconductor device and the second wide band gap semiconductor device are identical in structure and are composed of a semiconductor wafer, two electrodes (namely a hollow metal electrode and a solid metal electrode), a filling material and a supporting structure. The semiconductor wafer is connected with the hollow metal electrode and the solid metal electrode to form an opposite incident light type high-power wide band gap semiconductor device, and the structure of the opposite incident light type high-power wide band gap semiconductor device is the same as that of an opposite incident light type high-power wide band gap semiconductor device described in the patent application number of 201710616299.7: the semiconductor wafer adopts a multilayer electrode structure and consists of a high-voltage-resistant passivation layer, a metal ring, N layers of same semiconductor substrates, N layers of same transparent conductive layers and a silver plating layer. The method comprises the following steps that N layers of semiconductor substrates in a semiconductor wafer use high-resistance semiconductors as substrate materials, a first transparent conducting layer is prepared on the front surface of the first semiconductor substrate, a high-voltage-resistant passivation layer with an anti-reflection effect is prepared on the first transparent conducting layer, a metal ring is arranged on the periphery of the high-voltage-resistant passivation layer and clings to the first transparent conducting layer, and a hollow metal electrode is clinged to the upper surface of the metal ring; the N layers of semiconductor substrates are connected in series through the N layers of transparent conductive layers (namely 1 layer of transparent conductive layer is arranged between every two adjacent 2 layers of semiconductor substrates); and a silver coating with high reflectivity is prepared on the back surface of the N-th semiconductor substrate 3N, and the silver coating is connected with the solid metal electrode. The areas of the front surface and the back surface of the nth transparent conducting layer and the nth semiconductor wafer are the same.
The semiconductor substrate can be a square sheet or a circular sheet, the thickness h is 0.01mm to 0.1mm, the side length a is 1mm to 50mm when the semiconductor substrate is a square sheet, and the diameter D1 is 1mm to 50mm when the semiconductor substrate is a circular sheet. The material of the semiconductor substrate is selected from wide band gap semiconductors such as 4H-SiC, 6H-SiC or 2H-GaN, the withstand voltage requirement is 3-4MV/cm, and the recombination time of crystal carriers is less than 1ns.
The hollow metal electrode and the solid metal electrode are cylindrical, and the material can be stainless steel or brass; the ratio of the side length a (or diameter D1) of the semiconductor wafer to the diameter D2 of the hollow metal electrode is maintained between 1 and 1.5, the diameter of the solid metal electrode = D2; the hollow metal electrode and the solid metal electrode are connected with the semiconductor wafer by adopting conductive silver adhesive for bonding, and the silver adhesive is solidified after baking.
The supporting structure is a rectangular uncovered bottomless box made of polytetrafluoroethylene materials. The hollow metal electrode penetrates through the first side face of the supporting structure, one end of the hollow metal electrode is bonded with the metal ring on the front face of the first layer of semiconductor substrate in the semiconductor wafer, and the other end of the hollow metal electrode is connected with the output end of the first pulse forming device or the second pulse forming device; one end of the solid metal electrode is bonded with the back silver-plated layer of the N-th layer semiconductor substrate in the semiconductor wafer, and the other end of the solid metal electrode penetrates through the second side face of the supporting structure. The support structure of the first wide band gap semiconductor device is connected with the input end of the first current limiting resistor, and the support structure of the second wide band gap semiconductor device is connected with the input end of the second current limiting resistor; and filling materials are arranged among the semiconductor wafer, the hollow metal electrode, the solid metal electrode and the supporting structure, the filling materials are required to completely cover the semiconductor wafer, the hollow metal electrode and the solid metal electrode, the average withstand field strength of the filling materials is required to be more than or equal to 40kV/mm, when the wavelength of light is 200-1200 nm, the transmittance of the light is more than 99%, and the filling materials are preferably epoxy resin.
The first laser pulse and the second laser pulse acting on the first wide bandgap semiconductor device and the second wide bandgap semiconductor device should be two laser pulses, which may be a pair of sinusoidal (triangular, gaussian) laser pulses with a phase difference of 180 degrees (i.e. time complementary), and the laser frequency is adjustable, and may be free space output or optical fiber output within a range of 0.1GHz to 10 GHz.
The first current-limiting resistor and the second current-limiting resistor have the same resistance value, and a gold aluminum shell resistor with the resistance value larger than 10k omega and the power capacity larger than 50W can be selected to avoid the working current exceeding the current threshold of any element in the circuit.
The resistance value of the load resistor is the same as the equivalent impedance formed by the parallel connection of the first branch circuit and the second branch circuit, so that the output impedance matching is realized. The output impedance should be matched to the equivalent impedance to obtain maximum gain, maximum output power and maximum efficiency over the load resistance.
And secondly, simultaneously applying the first laser pulse, the second laser pulse and the direct-current voltage to a first wide band gap semiconductor device and a second wide band gap semiconductor device in the B-type push-pull amplifying circuit based on the wide band gap semiconductor devices.
2.1 starting the laser power supply, and obtaining a laser pulse signal with stable output after debugging and preheating for several minutes. The laser pulses may be transmitted through free space or optical fiber after being output by the laser. After being output by a laser, laser pulses are transmitted through air or an optical fiber, then pass through a hollow metal electrode, and then irradiate on a high-voltage-resistant passivation layer of a semiconductor wafer. Odd numbered sequence pulses (1, 3, \8230;) act on a first wide band gap semiconductor device as first laser pulses, and even numbered sequence pulses (2, 4, \8230;) act on a second wide band gap semiconductor device as second laser pulses. The initial time delay between the odd-numbered sequence pulse and the even-numbered sequence pulse is fixed, the delay is set within the range of 10 ps-10 ns, and the delay can be realized by setting the laser or constructing different modes such as time delay and time division light path, electro-optical modulation and the like.
2.2 setting output electrical parameters of the first power supply and the second power supply to enable the output current amplitudes of the first power supply and the second power supply to be the same, and simultaneously starting the first power supply and the second power supply. The direct current voltage generated by the first power supply is rectified into square wave voltage with the same pulse characteristic after passing through the first pulse forming device, the pulse width is dozens to hundreds of ns, and the square wave voltage acts on the first wide band gap semiconductor device. The direct-current voltage generated by the second power supply is rectified into square-wave voltage with the same pulse characteristic after passing through the second pulse forming device, the pulse width is dozens to hundreds of ns, and the square-wave voltage acts on the second wide-band-gap semiconductor device. It is noted that the first and second power supplies apply dc voltages at the beginning of the irradiation of the first and second laser pulses to ensure that the first and second laser pulses are applied to the first and second wide bandgap semiconductor devices simultaneously with the dc voltages of the first and second power supplies.
And thirdly, carrying out photoelectric microwave amplification on the B type push-pull amplifying circuit based on the wide-bandgap semiconductor device under the excitation of a photoelectric signal.
3.1 after a first laser pulse and a second laser pulse are uniformly irradiated on a high-voltage resistant passivation layer on the front surface of a semiconductor wafer through air or optical fibers and then through a hollow metal electrode, a first transparent conducting layer, a first layer of semiconductor substrate, a second transparent conducting layer, a second layer of semiconductor substrate, \8230;, an nth transparent conducting layer, an nth layer of semiconductor substrate, \8230;, an nth transparent conducting layer and an nth layer of semiconductor substrate are sequentially incident, at the moment, a first wide band gap semiconductor device and a second wide band gap semiconductor device work as light-operated variable resistors, the on-resistance of the first wide band gap semiconductor device and the second wide band gap semiconductor device is linearly changed along with the light intensity of high-energy pulse cluster laser, the first wide band gap semiconductor device and the second wide band gap semiconductor device work in a linear mode, namely, a photon is injected into the N layer of semiconductor substrate to generate a pair of hole electrons, and the electrons move under the action of an electric field generated by external voltage, and further generate current; the current generated by the mode has the same waveform and frequency with the incident laser; according to ohm's law ' I = U/R ', the pulse voltage U is unchanged during the modulation process, and the resistance R changes in inverse proportion to the light intensity, so that the current I1 output by the first wide band gap semiconductor device changes in direct proportion to the light intensity, and the current I2 output by the second wide band gap semiconductor device changes in direct proportion to the light intensity.
And 3.2 the laser time of the first laser pulse and the laser time of the second laser pulse are complementary, and the applied voltages are opposite to each other, so that the first wide band gap semiconductor device and the second wide band gap semiconductor device are conducted in one laser signal period. The single turn-on time of the first wide band gap semiconductor device or the second wide band gap semiconductor device is equivalent to the duration of a single pulse of the laser, so that the current I1 output by the first wide band gap semiconductor device and the current I2 output by the second wide band gap semiconductor device are both currents which change periodically, and the current change period is approximately equal to the laser signal period.
3.3 the current I1 output by the first wide band gap semiconductor device is converged after passing through the first current limiting resistor and the current I2 output by the second wide band gap semiconductor device is converged after passing through the second current limiting resistor to obtain a converged current.
3.4 the converged current flows through the load resistor to obtain a high-frequency electric signal which is modulated to be twice the modulation frequency of the laser pulse, the frequency is in GHz level, which means that the duration of a single electric pulse is less than 1ns, and under the excitation of external direct current electric power, the high-frequency electric signal on the load resistor has high power characteristic at the same time, which can reach MW level, and the photoelectric high-power microwave amplification is realized. If a radiation output component (such as a horn antenna or a parabolic antenna) is connected between the load resistor and the ground terminal, the radiation output component can radiate the microwave signal amplified by the photoelectricity outwards.
3.5 the first laser pulse and the second laser pulse end the irradiation and the first power supply and the second power supply are switched off accordingly.
Compared with the traditional high-power microwave generation method based on pulse power and relativistic vacuum electron tubes and the method for generating microwave signals by constructing the AB class amplification circuit by using GaAs, the method has the following advantages:
1. the B-class push-pull type amplification circuit based on the wide-bandgap semiconductor device designed in the first step has the advantages of simple structure, high device working voltage and high microwave output power, and the output power can reach 1MW level in the future according to the principle verification experiment that the output power is 50W, so that the unipolar limitation of the A-class amplification circuit on microwave amplification is eliminated, and the problem of low output power existing in the construction of the AB-class push-pull type microwave amplification circuit by using GaAs is effectively solved.
2. The invention expands the application range of the B-type push-pull amplifying circuit in radio frequency and microwave frequency bands, and eliminates the technical limit of the traditional transistor amplifying circuit by utilizing the material advantages of wide band gap semiconductors. In addition, the internal electric field of the semiconductor device with the multilayer electrodes is uniformly distributed, the voltage resistance is high, the breakdown is not easy, and high-power electric signals can be output.
3. The microwave signal output in the third step of the invention has flexible and adjustable frequency and has the advantage of intellectualization. In the wide band gap semiconductor device, in a linear working mode, a photon is injected into a semiconductor substrate to generate an electron (carrier), so that the current in the semiconductor substrate is completely controlled by a high repetition frequency pulse laser generator, and the semiconductor device can respond to an input optical signal with GHz and output an electric signal with GHz because the carrier in the semiconductor substrate has a recombination time of less than 1ns. The modulation frequency of the electric signal output by the wide band gap semiconductor device is consistent with that of the laser input into the device, and the output frequency mainly depends on the modulation frequency of the input laser, unlike the traditional high-power microwave device which only corresponds to one frequency point. By changing the modulation frequency of the incident laser, the modulation of the microwave frequency from 0.1GHz to 1GHz, namely, the modulation of 10-frequency multiplication can be realized.
Drawings
Fig. 1 is a circuit logic structure diagram of a class AB photoelectric microwave amplifier based on a wide band gap semiconductor device in the background art;
FIG. 2 is a general flow diagram of the present invention;
figure 3 is a circuit block diagram of a class B push-pull amplifier circuit based on wide bandgap semiconductor devices constructed in a first step of the present invention;
figure 4 is a block diagram of the wide bandgap semiconductor device of figure 3;
figure 5 is a diagram of a multi-layer electrode structure of the wide bandgap semiconductor wafer of figure 4;
FIG. 6 is an experimental layout for proof of the principle of the present invention with an output power of 50W;
figure 7 is a graph of time complementary laser pulse waveforms used to energize the wide bandgap semiconductor device of figure 6.
Detailed Description
As shown in fig. 2, the present invention comprises the steps of:
in a first step, a class B push-pull amplifying circuit based on wide band gap semiconductor devices is constructed, which is shown in fig. 3 and is composed of two power supplies (i.e., a first power supply 51 and a second power supply 52), two pulse forming devices (i.e., a first pulse forming device 61 and a second pulse forming device 62), two wide band gap semiconductor devices (i.e., a first wide band gap semiconductor device 71 and a second wide band gap semiconductor device 72), two current limiting resistors, a load resistor, and a ground terminal.
The first power supply 51 is connected with the first pulse forming device 61 through a high-voltage-resistant lead, and the first pulse forming device 61 is connected with the anode end of the first wide bandgap semiconductor device width 71 through a high-voltage-resistant lead; the first wide bandgap semiconductor device 71 is excited by the first input laser pulse 81, and the cathode terminal of the first wide bandgap semiconductor device 71 is connected to the first current limiting resistor 91 through a high voltage tolerant line to form a first shunt.
The second power supply 52 is connected to the second pulse forming device 62 by a high voltage tolerant lead, and the second pulse forming device 62 is connected to the anode terminal of the second wide bandgap semiconductor device 72 by a high voltage tolerant lead; the second wide bandgap semiconductor device 72 is excited by the second input laser pulse 82, and the cathode terminal of the second wide bandgap semiconductor device 72 is connected to a second current limiting resistor 92 by a high voltage tolerant line to form a second shunt.
The first and second branches are connected in parallel and then connected in series with a load resistor 93, the load resistor 93 being connected to the ground terminal 10.
The first power supply 51 and the second power supply 52 are both high voltage dc power supplies, and except for the opposite polarity of the output voltage, the other electrical parameters are the same, and a positive dc voltage signal and a negative dc voltage signal with the same amplitude are respectively output. The maximum value of the output voltage is not lower than 20kV and can be tuned.
The first pulse forming device 61 and the second pulse forming device 62 may be the same pulse forming line or the same pulse forming network, and for the first branch or the second branch, the characteristic impedance of the first pulse forming device 61 and the second pulse forming device 62 should be the same as the minimum resistance of the wide bandgap semiconductor device in the branch in which it is located in the on-state under laser irradiation. The first pulse forming device 61 and the second pulse forming device 62 are preferably solid-state pulse forming lines or solid-state pulse forming networks, square-wave pulses are required to be output, the pulse width is tens or hundreds of ns, the trigger jitter, the delay jitter and the rise time jitter are all in sub-ns order, the breakdown voltage is higher than 30kV, and the first pulse forming device 61 and the second pulse forming device 62 can be coaxial type or flat type solid-state pulse forming lines or coaxial type or flat type solid-state pulse forming networks.
The first wide bandgap semiconductor device 71 and the second wide bandgap semiconductor device 72 are identical in structure and, as shown in fig. 4, each consists of four parts, namely a semiconductor wafer 300, a hollow metal electrode 201 and a solid metal electrode 202, a filling material 100 and a support structure 101. The semiconductor wafer 300 is connected with the hollow metal electrode 201 and the solid metal electrode 202 to form an opposite light incident type high-power wide band gap semiconductor device, and the semiconductor wafer 300 adopts a multilayer electrode structure. As shown in fig. 5, the semiconductor wafer 300 is composed of a high voltage resistant passivation layer 1, a metal ring 2, a semiconductor substrate (31, 32 \ 8230; 3N, \8230; 3N) having the same N layer, a transparent conductive layer (41, 42 \8230; 4N, \8230; 4N) having the same N layer, and a silver plating layer 5. N layers of semiconductor substrates (31-3N) in the semiconductor wafer 300 use high-resistance semiconductors as substrate materials, a first transparent conductive layer 41 is prepared on the front surface of the first semiconductor substrate 31, a high-voltage resistant passivation layer 1 with an anti-reflection effect is prepared on the first transparent conductive layer 41, a metal ring 2 is arranged on the periphery of the high-voltage resistant passivation layer 1 and clings to the first transparent conductive layer 41, and the upper surface of the metal ring 2 clings to the hollow metal electrode 201; the N layers of semiconductor substrates (31, 32 \8230; 3N) are connected by N layers of transparent conductive layers (41, 42 \8230; 4N) (namely, 1 layer of transparent conductive layer is arranged between every two adjacent 2 layers of semiconductor substrates); a silver plating layer 5 with high reflectivity is prepared on the back of the N-th semiconductor substrate 3N, and the silver plating layer 5 is connected with the solid metal electrode 202. The front and back surfaces of the n-th transparent conductive layer 4n and the n-th semiconductor wafer 3n are the same in area.
The semiconductor substrate (31 to 3N) may be a square sheet or a circular sheet, and has a thickness h of 0.01mm to 0.1mm, a side length a of 1mm to 50mm in the case of the square sheet, and a diameter D1 of 1mm to 50mm in the case of the circular sheet. The material of the semiconductor substrate (31-3N) is selected from wide band gap semiconductors such as 4H-SiC, 6H-SiC or 2H-GaN, the withstand voltage requirement is 3-4MV/cm, and the recombination time of crystal carriers is less than 1ns.
The hollow metal electrode 201 and the solid metal electrode 202 are cylindrical, and the material can be stainless steel or brass; the ratio of the side length a (or diameter D1) of the semiconductor wafer to the diameter D2 of the hollow metal electrode 201 is maintained between 1 and 1.5, the diameter of the solid metal electrode 202 = D2; the hollow metal electrode 201 and the solid metal electrode 202 are connected with the semiconductor wafer 300 by adopting conductive silver paste for bonding, and the silver paste is solidified after baking.
The support structure 101 is a rectangular, uncovered, bottomless box fabricated from polytetrafluoroethylene material. The hollow metal electrode 201 penetrates through the first side surface 102 of the supporting structure 101, one end of the hollow metal electrode is bonded with the metal ring 2 on the front surface of the first layer semiconductor substrate 31 in the semiconductor wafer 300, and the other end of the hollow metal electrode is connected with the output end of the first pulse forming device 61 or the second pulse forming device 62; one end of the solid metal electrode 202 is bonded to the back silver plating layer 5 of the nth layer semiconductor substrate 3N in the semiconductor wafer 300, and the other end passes through the second side 103 of the support structure 101. The support structure 101 of the first wide bandgap semiconductor device 71 is connected to the input of a first current limiting resistor 91 and the support structure 101 of the second wide bandgap semiconductor device 72 is connected to the input of a second current limiting resistor 92; the filling material 100 is arranged among the semiconductor wafer 300, the hollow metal electrode 201, the solid metal electrode 202 and the supporting structure 101, the filling material 100 is required to completely cover the semiconductor wafer 300, the hollow metal electrode 201 and the solid metal electrode 202, the filling material 100 is required to have the average withstand field strength of more than or equal to 40kV/mm, when the light wavelength is 200-1200 nm, the transmittance of the light is more than 99%, and the filling material is preferably epoxy resin.
The first laser pulse 81 and the second laser pulse 82 applied to the first wide bandgap semiconductor device 71 and the second wide bandgap semiconductor device 72 should be two laser pulses, which may be a pair of sinusoidal (triangular, gaussian) laser pulses with a phase difference of 180 ° (i.e., complementary in time), and the laser frequency may be adjustable, and may be free space output or fiber output within a range of 0.1GHz to 10 GHz.
The first current limiting resistor 91 and the second current limiting resistor 92 have the same resistance value, and a gold aluminum shell resistor with the resistance value larger than 10k Ω and the power capacity larger than 50W can be selected, so that the working current is prevented from exceeding the current threshold of any element in the circuit.
The resistance of the load resistor 93 should be the same as the equivalent impedance formed by the parallel connection of the first branch circuit and the second branch circuit, so as to implement output impedance matching. The output impedance should be matched to the equivalent impedance to obtain maximum gain, maximum output power and maximum efficiency across the load resistor 93.
In a second step, the first laser pulse 81 and the second laser pulse 82 act on the first wide bandgap semiconductor device 71 and the second wide bandgap semiconductor device 72 in a class B push-pull amplification circuit based on wide bandgap semiconductor devices simultaneously with the dc voltage.
2.1 starting the laser power supply, and obtaining a laser pulse signal with stable output after debugging and preheating for several minutes. The laser pulses may be transmitted through free space or optical fiber after being output by the laser. After being output by a laser, the laser pulse is transmitted through air or an optical fiber, then passes through the hollow metal electrode 201, and then is irradiated on the high voltage resistant passivation layer 1 of the semiconductor wafer 300. The odd-numbered sequence pulses (1, 3, \8230;) are applied as first laser pulses 81 to the first wide band gap semiconductor device 71 and the even-numbered sequence pulses (2, 4, \8230;) are applied as second laser pulses 82 to the second wide band gap semiconductor device 72. The initial time delay between the odd-numbered sequence pulse and the even-numbered sequence pulse is fixed, the delay is set within the range of 10 ps-10 ns, and the delay can be realized by setting the laser or constructing different modes such as time delay and time division light path, electro-optical modulation and the like.
2.2 setting the output electrical parameters of the first power supply 51 and the second power supply 52 to make the output currents of the first power supply 51 and the second power supply 52 have the same magnitude, and simultaneously turning on the first power supply 51 and the second power supply 52. The direct-current voltage generated by the first power supply 51 is rectified into a square-wave voltage having the same pulse characteristics after passing through the first pulse forming device 61, and the square-wave voltage has a pulse width of several tens to several hundreds ns and acts on the first wide bandgap semiconductor device 71. The direct-current voltage generated by the second power source 52 is rectified into a square-wave voltage having the same pulse characteristic, having a pulse width of several tens to several hundreds ns, by the second pulse forming device 62, and is applied to the second wide bandgap semiconductor device 72. It is noted that the first power supply 51 and the second power supply 52 only apply a dc voltage when the first laser pulse 81 and the second laser pulse 82 begin to irradiate, to ensure that the first laser pulse 81 and the second laser pulse 82 act on the first wide bandgap semiconductor device 71 and the second wide bandgap semiconductor device 72 simultaneously with the dc voltages of the first power supply 51 and the second power supply 52.
And thirdly, carrying out photoelectric microwave amplification on the B class push-pull amplifying circuit based on the wide band gap semiconductor device under the excitation of a photoelectric signal.
3.1 after a first laser pulse 81 and a second laser pulse 82 are uniformly irradiated onto a high-voltage resistant passivation layer 1 on the front surface of a semiconductor wafer 300 through air or optical fibers and then through a hollow metal electrode 201, the first laser pulse 41, a first layer of semiconductor substrate 31, a second transparent conductive layer 42, a second layer of semiconductor substrate 32, \\ 8230;. N transparent conductive layer 4N, an N layer of semiconductor substrate 3N, \ 8230;. N transparent conductive layer 4N, and an N layer of semiconductor substrate 3N are sequentially incident, at this time, the first wide band gap semiconductor device 71 and the second wide band gap semiconductor device 72 operate as a light-operated variable resistor, the on-resistance thereof linearly changes with the light intensity of high-energy pulse cluster laser, and the first wide band gap semiconductor device 71 and the second wide band gap semiconductor device 72 operate in a linear mode, i.e. one photon is incident into the N layer of semiconductor substrate (31, 32, \\ 8230; 3N, \\\\ 8230; 3N) to generate a pair of holes and electrons move under the action of an electric field generated by an external voltage, thereby generating a current; the current generated by the mode has the same waveform and frequency with the incident laser; in this operation mode, according to ohm's law "I = U/R", the pulse voltage U is not changed during the modulation process, and the resistance R is changed in inverse proportion to the light intensity, so that the current I1 output from the first wide bandgap semiconductor device 71 and the light intensity are changed in direct proportion, and the current I2 output from the second wide bandgap semiconductor device 72 and the light intensity are also changed in direct proportion.
3.2 the first laser pulse 81 and the second laser pulse 82 are complementary in laser time and the applied voltages are opposite to each other, so that the first wide band gap semiconductor device 71 and the second wide band gap semiconductor device 72 are turned on during one laser signal period. The single on-time of the first wide bandgap semiconductor device 71 or the second wide bandgap semiconductor device 72 is equivalent to the duration of the single pulse of the laser, so that the current I1 output by the first wide bandgap semiconductor device 71 and the current I2 output by the second wide bandgap semiconductor device 72 are both currents that change periodically, and the period of the current change is approximately equal to the period of the laser signal.
3.3 the current I1 output by the first wide band gap semiconductor device 71 passes through the first current limiting resistor 91, and the current I2 output by the second wide band gap semiconductor device 72 passes through the second current limiting resistor 92, and then they are combined to obtain a combined current.
3.4 the converged current flows through the load resistor 93 to obtain a high-frequency electric signal modulated to be twice the modulation frequency of the laser pulse, wherein the frequency is in GHz level, which means that the duration of a single electric pulse is less than 1ns, and under the excitation of external direct current electric power, the high-frequency electric signal on the load resistor 93 has high-power characteristics at the same time, which can reach MW level, thereby realizing photoelectric high-power microwave amplification. If a radiation output component (e.g., a horn antenna, a parabolic antenna) is connected between the load resistor 93 and the ground terminal 10, the radiation output component can radiate the microwave signal amplified by the photo-electricity to the outside.
3.5 the first laser pulse 81 and the second laser pulse 82 end the irradiation, the first power supply 51 and the second power supply 52 are switched off accordingly.
FIG. 6 is an experimental layout for proof of principle of 50W output power; the experimental device mainly comprises an optical part, a circuit part and two high-voltage power supplies.
A Nd-YAG Q-switched laser with the full width at half maximum of 1.7ns and the wavelength of 532nm is used for generating optical pulses, and a mirror and a beam splitter are used for constructing a first laser pulse 81 and a second laser pulse 82 which are complementary in a beam splitting and time delay mode. The first laser pulse 81 and the second laser pulse 82 each comprise two light pulses, both of gaussian type, with a peak light power of 80kW and a pulse rise time of 1ns.
According to the propagation speed of light in air of about 3 × 10 8 m/s, adjusting the position of the mirror can change the length of the delay between the first laser pulse 81 and the second laser pulse 82, the length of the delay between two light pulses contained in the first laser pulse 81, and the length of the delay between two light pulses contained in the second laser pulse 82. The waveforms of the first laser pulse 81 and the second laser pulse 82 obtained by the experiment are shown in fig. 7, with the ordinate being the laser fluence (which may be in arbitrary units, and here only the relative magnitude is shown, regardless of what is actually the case), the abscissa being the time (in nanoseconds), the solid line representing the first input pulse 81 (odd-numbered series of pulses, including pulse 1 and pulse 3), and the dotted line representing the second input pulse 82 (even-numbered series of pulses, including pulse 2 and pulse 4). The time delay between the first laser pulse 81 and the second laser pulse 82 (i.e., the time delay between pulse 1 and pulse 2) is 3.7ns, the time delay between two light pulses contained in the first laser pulse 81 (i.e., the time delay between pulse 1 and pulse 3) is 7.4ns, and the time delay between two light pulses contained in the second laser pulse 82 (i.e., the time delay between pulse 2 and pulse 4) is also 7.4ns.
The first power supply 51 and the second power supply 52 are both high voltage dc power supplies. The first pulse forming line 61 adopts a first capacitor C 1 Instead, the second pulse forming line uses a second capacitor C 2 Instead of, C 1 And C 2 Both at 4nF and a load resistance 93 of 25 Ω. Measuring the current through a load resistor 93 by means of a current sensing resistor (CVR) 94, i.e. amplificationThe output current of the circuit. Load resistor 93 is connected to ground terminal 10.
The first wide bandgap semiconductor device 71 and the second wide bandgap semiconductor device 72 each employ a circular 6H — SiC substrate having a side of 1cm and a thickness of 200 μm.
The results of the experiment are shown in table 1: (1) The first laser pulse 81 and the second laser pulse 82 both have a power of P 0 ，P 0 =80kW; (2) Consuming electric power P HV =1.84kW; (3) Output power P of load resistor 93 out ＝I(t) 2 R load =0.047kW; (4) Push-pull amplifier circuit efficiency Eff. = P out /P HV =2.5%. It can be seen that the output power P of the load resistor 93 out And the push-pull amplifier circuit efficiency eff. Are low because of the low quantum efficiency of the first wide band gap semiconductor device 71 and the second wide band gap semiconductor device 72 at present. Theory and simulation show that higher quantum efficiency will reduce the on-resistance of the first wide bandgap semiconductor device 71 and the second wide bandgap semiconductor device 72 to below 10 Ω, which will greatly increase the photocurrent and voltage across the load resistor 93, improving the output power and efficiency up to 78.5%.
The first table is a part of typical simulation results, the second row in the table is the actual result of the experimental quantum efficiency, the quantum efficiency eta is lower and about 0.002, and the third row and the fourth row are the results obtained by simulation, wherein the quantum efficiency eta and the bias voltage V HV The output power P of the push-pull amplifying circuit can be improved in the future only by greatly improving out And efficiency eff. Wherein the fourth line outputs power P out The power reaches 1100kW (namely 1.1 MW), which indicates that the photoelectric microwave amplifying circuit designed in the first step of the invention has the potential of realizing megawatt output power. The experiment and simulation results show that the current low amplification efficiency is caused by the low quantum efficiency eta of the current semiconductor material, and the low quantum efficiency eta is mainly related to doping, light absorption and other non-circuit factors. The microwave amplification method proposed by the present invention is relatively superior only in terms of the amplification circuit designed in the first step of the present invention. As long as the quantum efficiency eta of the wide-band-gap semiconductor device material is improved, photoelectric microwave amplification is carried out according to the push-pull amplification circuit after the quantum efficiency eta is improvedSignificantly higher efficiency and power can be achieved. At present, there are two methods for improving quantum efficiency eta: one is to improve the external quantum efficiency (light absorption efficiency). The structure of the wide band gap semiconductor device (such as changing the configuration of a wafer, arranging a resonant cavity and plating an antireflection film) is improved by selecting a proper transmission medium (optical fiber or optical waveguide) and an incident mode, so that modulated laser output by a pulse light source is coupled into the wide band gap semiconductor as much as possible and absorbed by the wide band gap semiconductor. And the internal quantum efficiency is improved. The material properties of the wide band gap semiconductor are improved, including controlling reasonable doping concentration and proportion, reducing defect energy level introduced in the preparation process and the like, so as to change the carrier characteristics (such as carrier service life and material light absorption coefficient). The effect of the present invention in terms of improving efficiency and power is therefore remarkable.
TABLE 1 microwave amplification efficiency under different parameters
Claims (14)
1. A photoelectric high-power microwave amplification method based on a wide-bandgap semiconductor device is characterized by comprising the following steps:
the method comprises the following steps that firstly, a class B push-pull type amplifying circuit based on a wide band gap semiconductor device is constructed, and the class B push-pull type amplifying circuit based on the wide band gap semiconductor device consists of two power supplies, namely a first power supply (51) and a second power supply (52), two pulse forming devices, namely a first pulse forming device (61) and a second pulse forming device (62), two wide band gap semiconductor devices, namely a first wide band gap semiconductor device (71) and a second wide band gap semiconductor device (72), two current limiting resistors, namely a first current limiting resistor (91) and a second current limiting resistor (92), a load resistor (93) and a grounding terminal (10);
the first power supply (51) is connected with the first pulse forming device (61) through a high-voltage-resistant lead, and the first pulse forming device (61) is connected with the anode end of the first wide bandgap semiconductor device (71) through a high-voltage-resistant lead; the first wide band gap semiconductor device (71) is excited by a first path of input laser pulse (81), and the cathode end of the first wide band gap semiconductor device (71) is connected with a first current limiting resistor (91) through a high-voltage-resistant wire to form a first branch path;
the second power supply (52) is connected with the second pulse forming device (62) through a high-voltage-resistant lead, and the second pulse forming device (62) is connected with the anode end of the second wide-bandgap semiconductor device (72) through a high-voltage-resistant lead; the second wide band gap semiconductor device (72) is excited by the second path of input laser pulse (82), and the cathode end of the second wide band gap semiconductor device (72) is connected with a second current limiting resistor (92) through a high-voltage-resistant wire to form a second shunt;
the first shunt circuit and the second shunt circuit are connected in parallel and then are connected in series with a load resistor (93), and the load resistor (93) is connected with a grounding terminal (10);
the first power supply (51) and the second power supply (52) are both high-voltage direct-current power supplies, except that the output voltage polarity is opposite, the other electrical parameters are the same, and a positive direct-current voltage signal, a negative direct-current voltage signal and a positive direct-current voltage signal are respectively output, wherein the positive direct-current voltage signal and the negative direct-current voltage signal have the same amplitude;
the first pulse forming device (61) and the second pulse forming device (62) are the same pulse forming line or the same pulse forming network, and the characteristic impedance of the first pulse forming device (61) and the second pulse forming device (62) is the same as the minimum resistance of the on-state of the wide band gap semiconductor device in the shunt where the first pulse forming device and the second pulse forming device are positioned under the laser irradiation;
the first wide band gap semiconductor device (71) and the second wide band gap semiconductor device (72) are identical in structure and are composed of a semiconductor wafer (300), a hollow metal electrode (201), a solid metal electrode (202), a filling material (100) and a supporting structure (101); the semiconductor wafer (300), the hollow metal electrode (201) and the solid metal electrode (202) are connected to form an opposite incident light type high-power wide-band gap semiconductor device; the semiconductor wafer (300) adopts a multi-layer electrode structure, and the semiconductor wafer (300) is composed of a high-voltage resistant passivation layer (1), a metal ring (2), N layers of same semiconductor substrates (31, 32, \8230;, 3N), N layers of same transparent conductive layers (41, 42, \8230;, 4N) and a silver-plated layer (5); the method comprises the following steps that N layers of semiconductor substrates (31, 32, \ 8230; 3N, \ 8230; 3N) in a semiconductor wafer (300) use high-resistance semiconductors as substrate materials, a first transparent conductive layer (41) is prepared on the front surface of the first semiconductor substrate (31), a high-voltage-resistant passivation layer (1) is prepared on the first transparent conductive layer (41), a metal ring (2) is arranged on the periphery of the high-voltage-resistant passivation layer (1) and clings to the first transparent conductive layer (41), and a hollow metal electrode (201) is clinged to the upper surface of the metal ring (2); n-layer semiconductor substrates (31, 32, \8230;, 3N, \8230;, 3N) are connected by N-layer transparent conductive layers (41, 42, \8230;, 4N, \8230;, 4N); a silver plating layer (5) with high reflectivity is prepared on the back of the Nth layer of semiconductor substrate (3N), and the silver plating layer (5) is connected with the solid metal electrode (202); the areas of the front surface and the back surface of the nth transparent conducting layer (4 n) and the nth semiconductor wafer (3 n) are the same;
the hollow metal electrode (201) and the solid metal electrode (202) are cylindrical and made of stainless steel or brass; the diameter of the hollow metal electrode (201) is D2, and the diameter of the solid metal electrode (202 = D2; the hollow metal electrode (201) and the solid metal electrode (202) are bonded with the semiconductor wafer (300) by adopting conductive silver adhesive;
the supporting structure (101) is a rectangular uncovered bottomless box processed by polytetrafluoroethylene materials; the hollow metal electrode (201) penetrates through the first side face (102) of the supporting structure (101), one end of the hollow metal electrode is bonded with the metal ring (2) on the front face of the first layer of semiconductor substrate (31) in the semiconductor wafer (300), and the other end of the hollow metal electrode is connected with the output end of the first pulse forming device (61) or the second pulse forming device (62); one end of the solid metal electrode (202) is adhered to the back silver coating (5) of the Nth layer of semiconductor substrate (3N) in the semiconductor wafer (300), and the other end passes through the second side surface (103) of the supporting structure (101); the support structure (101) of the first wide band gap semiconductor device (71) is connected to the input of a first current limiting resistor (91), and the support structure (101) of the second wide band gap semiconductor device (72) is connected to the input of a second current limiting resistor (92); a filling material (100) is arranged among the semiconductor wafer (300), the hollow metal electrode (201), the solid metal electrode (202) and the supporting structure (101), and the filling material (100) is required to completely cover the semiconductor wafer (300), the hollow metal electrode (201) and the solid metal electrode (202);
the first laser pulse (81) and the second laser pulse (82) acting on the first wide band gap semiconductor device (71) and the second wide band gap semiconductor device (72) are two laser pulses, are a pair of laser pulses with a phase difference of 180 degrees, have adjustable laser frequency, and are free space output or optical fiber output;
the first current limiting resistor (91) and the second current limiting resistor (92) have the same resistance value;
the resistance value of the load resistor (93) is the same as the equivalent impedance formed by the first shunt circuit and the second shunt circuit which are connected in parallel;
in a second step, the first laser pulse (81) and the second laser pulse (82) are applied simultaneously with a dc voltage to a first wide band gap semiconductor device (71) and a second wide band gap semiconductor device (72) in a class B push-pull amplification circuit based on wide band gap semiconductor devices by:
2.1, starting a laser power supply, debugging and preheating to obtain a laser pulse signal with stable output; after being output by a laser, laser pulses are transmitted through air or an optical fiber, pass through the hollow metal electrode (201), and irradiate on the high-voltage-resistant passivation layer (1) of the semiconductor wafer (300); odd-numbered sequential pulses as first laser pulses (81) applied to the first wide bandgap semiconductor device (71), and even-numbered sequential pulses as second laser pulses (82) applied to the second wide bandgap semiconductor device (72); the initial time delay between the odd-numbered sequence pulses and the even-numbered sequence pulses is fixed;
2.2 setting output electrical parameters of the first power supply (51) and the second power supply (52) to enable the output current amplitudes of the first power supply and the second power supply to be the same, and simultaneously starting the first power supply (51) and the second power supply (52); a direct current voltage generated by a first power supply (51) is rectified into a square wave voltage with the same pulse characteristic after passing through a first pulse forming device (61), the pulse width of the square wave voltage is tens to hundreds of ns, and the square wave voltage acts on a first wide band gap semiconductor device (71); the direct current voltage generated by the second power supply (52) is rectified into square wave voltage with the same pulse characteristic after passing through the second pulse forming device (62), the pulse width is dozens to hundreds of ns, and the square wave voltage acts on the second wide-band gap semiconductor device (72);
thirdly, the class B push-pull amplifying circuit based on the wide band gap semiconductor device carries out photoelectric microwave amplification under the excitation of photoelectric signals, and the method comprises the following steps:
3.1 a first laser pulse (81) and a second laser pulse (82) are sequentially incident to a first transparent conducting layer (41), a first layer of semiconductor substrate (31), a second transparent conducting layer (42), a second layer of semiconductor substrate (32), \8230;, an N-th transparent conducting layer (4N), an N-th layer of semiconductor substrate (3N), a first wide band gap semiconductor device (71) and a second wide band gap semiconductor device (72) work as light-operated variable resistors, the on-resistances of the first wide band gap semiconductor device (71) and the second wide band gap semiconductor device (72) are linearly changed along with the light intensity of high-energy pulse cluster laser, namely, one photon is incident into the N-layer semiconductor substrate (31, 32, \8230; 3N, \\ 8230; 3N, 3N) to generate a pair of hole electrons, and the electrons move under the action of an electric field generated by external voltage, thereby generating current; the current I1 output by the first wide band gap semiconductor device (71) and the light intensity are changed in direct proportion, and the current I2 output by the second wide band gap semiconductor device (72) and the light intensity are also changed in direct proportion;
3.2 the first laser pulse (81) and the second laser pulse (82) have complementary laser times and opposite applied voltages, so that the first wide band gap semiconductor device (71) and the second wide band gap semiconductor device (72) are turned on within one laser signal period; the single conduction time of the first wide band gap semiconductor device (71) or the second wide band gap semiconductor device (72) is equivalent to the duration of a single pulse of the laser, namely, the current I1 output by the first wide band gap semiconductor device (71) and the current I2 output by the second wide band gap semiconductor device (72) are both currents which change periodically, and the period of the current change is approximately equal to the period of the laser signal;
3.3 the current I1 output by the first wide band gap semiconductor device (71) passes through the first current limiting resistor (91), and the current I2 output by the second wide band gap semiconductor device (72) passes through the second current limiting resistor (92) and then is merged to obtain merged current;
3.4 the converged current flows through a load resistor (93) to obtain a high-frequency electric signal modulated to be twice the frequency of the laser pulse modulation, and the high-frequency electric signal on the load resistor (93) has high-power characteristics under the excitation of external direct current electric power;
3.5 the first laser pulse (81) and the second laser pulse (82) end the irradiation, the first power supply (51) and the second power supply (52) being switched off.
2. An opto-electronic high power microwave amplification method based on wide bandgap semiconductor devices according to claim 1 characterized in that said first power supply (51) and said second power supply (52) have a maximum output voltage not lower than 20kV and are tunable.
3. The photoelectric high-power microwave amplification method based on wide-bandgap semiconductor device according to claim 1, wherein the first pulse forming device (61) and the second pulse forming device (62) are solid-state pulse forming lines or solid-state pulse forming networks, and are required to output square-wave pulses, the pulse width is tens or hundreds of ns, the trigger jitter, the delay jitter and the rise time jitter are all in sub-ns order, and the breakdown voltage is higher than 30kV.
4. The method according to claim 3, wherein the first pulse forming device (61) and the second pulse forming device (62) are solid-state pulse forming lines of coaxial type or slab type, or solid-state pulse forming networks.
5. The photoelectric high-power microwave amplification method based on wide bandgap semiconductor device according to claim 1, wherein said semiconductor substrate (31, 32, \8230;, 3N) is a square or circular sheet with a thickness h ranging from 0.01mm to 0.1mm, a side length a ranging from 1mm to 50mm in the case of square sheet, and a diameter D1 ranging from 1mm to 50mm in the case of circular sheet; the semiconductor substrate (31, 32, \8230;, 3N) is made of wide band gap semiconductor, the withstand voltage is required to be 3-4MV/cm, and the recombination time of crystal carriers is less than 1ns.
6. A method of opto-electronic high power microwave amplification based on wide band gap semiconductor devices according to claim 5 characterized in that the material of the semiconductor substrate (31, 32; 8230; 3N; 8230; 3N) is 4H-SiC or 6H-SiC or 2H-GaN.
7. The photoelectric high-power microwave amplification method based on wide bandgap semiconductor device of claim 1, wherein the ratio of the side length a or diameter D1 of the semiconductor wafer (300) to the diameter D2 of the hollow metal electrode (201) is between 1 and 1.5.
8. The photoelectric high-power microwave amplification method based on wide bandgap semiconductor device of claim 1, wherein the average withstanding field strength of the filling material (100) is required to be greater than or equal to 40kV/mm, and the transmittance of light is greater than 99% when the wavelength of light is 200 nm-1200 nm.
9. The method for optoelectronic high power microwave amplification based on wide bandgap semiconductor device as claimed in claim 8, wherein said filling material (100) is epoxy resin.
10. The optoelectronic high power microwave amplification method based on wide bandgap semiconductor device as claimed in claim 1, characterized in that said first laser pulse (81) and second laser pulse (82) are sinusoidal or triangular or gaussian laser pulses with laser frequency in the range of 0.1GHz to 10 GHz.
11. The photoelectric high-power microwave amplification method based on wide bandgap semiconductor device of claim 1, wherein said first current limiting resistor (91) and said second current limiting resistor (92) are gold aluminum shell resistors with resistance greater than 10k Ω and power capacity greater than 50W.
12. The method of claim 1, wherein 2.1 steps of the initial time delay between the odd-numbered sequence of pulses and the even-numbered sequence of pulses is set in the range of 10ps to 10 ns.
13. The method for optoelectronic high power microwave amplification based on wide bandgap semiconductor device as claimed in claim 12, wherein said method for setting initial time delay between odd numbered sequence of pulses and even numbered sequence of pulses is by laser itself setting or by method of constructing time delay and time division optical path or by electro-optical modulation method.
14. The photoelectric high-power microwave amplification method based on the wide bandgap semiconductor device of claim 1, wherein a radiation output module is connected between the load resistor (93) and the ground terminal (10), and the high-frequency electrical signal obtained in the step 3.4 is radiated to the outside to output a microwave signal.
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| 半导体激光器驱动电路的计算机仿真分析;张晶等;《计算机仿真》;20091215(第12期);全文 * |
| 基于光电导开关的高功率超宽带微波脉冲产生技术;张同意等;《微波学报》;20021030(第03期);全文 * |
| 张晶等.半导体激光器驱动电路的计算机仿真分析.《计算机仿真》.2009,(第12期), * |
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