A photoconductive antenna chip rapid testing device and a testing method thereof

Abstract

The application relates to the technical field of photoconductive antenna chip testing, and provides a photoconductive antenna chip rapid testing device and a testing method thereof, which comprises a light source, a first testing light path, a second testing light path, a coupling trigger module, a to-be-tested module, a data acquisition module and a data processing module. Two light sources with a frequency difference are used in combination with a laser scanning galvanometer and a laser lens to respectively excite a close-to-mounted transmitting chip and a detecting chip, and a bias voltage is applied to the transmitting chip; the transmitting chip generates a terahertz wave under the joint action of the laser and the bias voltage; the terahertz wave is radiated to the detecting chip, so that the detecting chip generates an electric signal; the quality of the chip is judged by detecting and analyzing the electric signal; the pipeline rapid testing of the chip is realized; and the testing efficiency of the chip is significantly improved.

Description

Technical Field

[0001] This invention relates to the field of photoconductive antenna chip testing technology, and provides a rapid testing device and method for photoconductive antenna chips. Background Technology

[0002] In the field of terahertz technology, photo-excited photoconductive antennas are indispensable key components of terahertz spectral analysis instruments, used for measuring and analyzing the parameters and characteristics of materials in the terahertz band. However, because antenna chip fabrication is still a cutting-edge technology, the related crystal growth and chip processing technologies are not yet mature. Chips produced can vary in quality between different batches, and even within the same batch. Users are often unsure whether the chips they purchase are of good quality. Therefore, in actual production and use, it is necessary to first build a system to test the performance of the photoconductive antenna chips. Currently, there is a lack of dedicated rapid testing methods for terahertz photoconductive antenna chips. They are usually delivered directly to users, who then have to build complex debugging devices for testing during use. This testing process is slow, and if a chip malfunctions, it needs to be re-tuned, which is time-consuming, labor-intensive, and extremely inefficient.

[0003] Specific devices such as Figure 1 As shown, laser excitation of the transmitting and detecting chips is achieved by splitting the beam of a single laser. Terahertz signal scanning and testing are performed using a traditional optical delayer. Alignment between the excitation laser and the chip is achieved by adjusting a laser lens mounted on a multi-dimensional displacement stage. Alignment of the terahertz beam between the transmitting and detecting chips is achieved by adjusting a hemispherical lens and a terahertz lens mounted on the multi-dimensional displacement stage. In specific debugging, firstly, at the laser excitation end, the photoconductive antenna chip and the excitation laser need to be aligned and debugged. During debugging, a traditional optical delayer is typically used for scanning. Due to the limited scanning range of the optical delayer, the optical paths of the transmitting and detecting lasers need to be precisely adjusted to achieve the optical path length for coherent detection. Then, mechanical delay scanning is performed near the coherence peak. This method requires adjusting the optical path, and the mechanical delay scanning speed is slow. Prolonged scanning and debugging can cause wear on the delay line, requiring readjustment of the optical path after replacement. Secondly, at the terahertz radiation and terahertz detection ends, further adjustments to the focusing and collimation of the terahertz beam are needed using a hemispherical lens and a terahertz lens to achieve terahertz signal testing. The slow scanning speed of optical retarder means that adjustments in each dimension cannot be made in real time. Furthermore, since many dimensions need adjustment, this method is extremely time-consuming. After debugging one pair of chips, complex optical path adjustments are required again before testing the next pair. If the chip's performance is poor or it is damaged, all of the above work is wasted, resulting in extremely low efficiency. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a rapid testing device for photoconductive antenna chips, comprising:

[0005] A light source that emits laser M and laser S with a locked repetition frequency, wherein there is a repetition frequency difference between laser M and laser S;

[0006] The first test optical path includes a first coupler, a first laser scanning galvanometer, and a first laser lens. The first coupler splits and distributes the laser beam M, which is split into laser M1 and laser M2. Laser M1 is output to the first laser scanning galvanometer, which controls the deflection of the laser beam. The first laser lens focuses the laser beam.

[0007] The second test optical path includes a second coupler, a second laser scanning galvanometer, and a second laser lens. The second coupler splits and distributes the laser S, which is split into laser S1 and laser S2. Laser S1 is output to the second laser scanning galvanometer, which controls the deflection of the laser beam. The second laser lens focuses the laser.

[0008] The coupling triggering module includes a third coupler and a triggering module. The third coupler is a parallel beam coupler. The laser M2 and laser S2 are output to the third coupler and then combined into a single beam. The triggering module collects the parallel beam laser that generates coherent interaction and generates a triggering signal.

[0009] The module under test includes a mounting bracket, a bias voltage module, and a transmitting chip and a detecting chip mounted in the mounting bracket. The bias voltage module applies a bias voltage to the transmitting chip, the laser M1 excites the transmitting chip to generate a terahertz wave, and the laser S1 excites the detecting chip to generate an electrical signal under the radiation of the terahertz wave.

[0010] A data acquisition module that receives trigger signals and electrical signals from the detection chip;

[0011] The data processing module processes the test results.

[0012] Specifically, the module under test is mounted on the conveying device, and through holes are provided on the mounting sides of the transmitting chip and the detection chip in the mounting bracket and at the bottom of the conveyor belt. The laser passes through the through holes and is focused onto the chip under test.

[0013] Specifically, the mounting bracket is provided with a transmitter chip electrode holder and a detector chip electrode holder. The transmitter chip electrode holder is electrically connected to the bias voltage module, and the detector chip electrode holder is communicatively connected to the data acquisition module.

[0014] Specifically, the electrode holders of the transmitting chip and the detector chip are movable, and the electrical input position of the bias voltage and the electrical output position from the detector chip to the data acquisition module can be periodically moved by a transmission device as the detection process progresses.

[0015] Specifically, the transmitting chip and the detecting chip are arranged close to each other, with a spacing of 1mm-5mm between them. A standard etalon device is arranged between the transmitting chip and the detecting chip to evaluate the quality of the tested terahertz signal.

[0016] Specifically, the data acquisition module includes two channels: a trigger signal channel and an electrical signal acquisition channel. The trigger signal channel acquires the trigger signal generated by the trigger module to control the starting position of the data acquisition module. The electrical signal acquisition channel acquires multiple reflected pulse signals obtained from the electrical signals of the detection chip.

[0017] Specifically, the data processing module transforms the multiple reflected pulses of the terahertz signal in the time domain into continuous sinusoidal pulses in the frequency domain through Fourier transform, and judges the signal quality of the terahertz pulse by counting the number of sinusoidal periods measured in the frequency domain.

[0018] This invention also provides a rapid testing method for photoconductive antenna chips, comprising:

[0019] S1: Two beams with a repetition frequency difference Δf are emitted towards the module under test mounted at the test location on the transmission device. R Laser M and laser S are split into laser M1 and laser M2, and laser S is split into laser S1 and laser S2.

[0020] S2: The parallel laser M2 and laser S2 form a periodic spike signal due to coherence, which activates the trigger module to generate a trigger signal. The trigger signal triggers the acquisition module to acquire the electrical signal.

[0021] S3: Laser M1 and laser S1 are rapidly scanned and excited by the laser scanning galvanometer and the laser lens. At the same time, a bias voltage is applied to the transmitting chip, and the transmitting chip emits a terahertz signal. After passing through the etalon device, multiple reflection pulses appear in the time domain. The detection chip generates an electrical signal under the radiation of the terahertz wave and outputs it to the data acquisition module.

[0022] S4: The trigger signal channel in the data acquisition module acquires the trigger signal generated by the trigger module to control the starting position of the data acquisition module; the electrical signal acquisition channel acquires multiple reflected pulse signals obtained from the electrical signal of the detection chip.

[0023] S5: The data processing module processes multiple reflected pulse signals, transforms them into continuous sinusoidal pulses in the frequency domain after Fourier transform, counts the number of sinusoidal periods measured in the frequency domain, and determines whether the chip quality in the module under test is qualified by judging whether the number of sinusoidal periods is greater than the expected number.

[0024] S6: The conveying device moves the next module under test to the test point and repeats the above steps;

[0025] S7: Record and filter the modules under test that failed the test, take out the transmitter and detector chips that failed the test, and combine the transmitter and detector chips that failed the test with the transmitter and detector chips that passed the test respectively and retest them to identify the problematic chips.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] (1) The present invention provides a rapid testing device for a photoconductive antenna chip pipeline. Two light sources with locked repetition frequencies are combined with a laser scanning galvanometer and a laser lens to excite a closely mounted transmitting chip and a detector chip respectively. A bias voltage is applied to the transmitting chip. The transmitting chip generates a terahertz wave under the combined action of the laser and the bias voltage. The terahertz wave radiates onto the detector chip, causing the detector chip to generate an electrical signal. The chip quality is judged by detecting and analyzing the electrical signal.

[0028] (2) The test frequency of the present invention is the repetition frequency difference between two laser beams, which can reach tens of kilohertz. It can complete the chip test in a short time, and the test time only takes a few seconds. It can avoid the complicated debugging process and realize the rapid testing of the chip in a pipeline, which significantly improves the chip testing efficiency. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of an existing chip testing device;

[0030] Figure 2 This is a schematic diagram of the test structure of the present invention;

[0031] Figure 3 This is a schematic diagram of the module under test.

[0032] Reference numerals: 1. Light source; 2. First coupler; 3. Second coupler; 4. Third coupler; 5. Trigger module; 6. First laser scanning galvanometer; 7. Second laser scanning galvanometer; 8. First laser lens; 9. Second laser lens; 10. Module under test; 11. Data acquisition module; 12. Bias voltage module; 13. Data processing module; 14. Transmission device; 15. Mounting bracket; 16. Transmitting chip; 17. Detecting chip; 18. Ether device; 19. Transmitting chip electrode holder; 20. Detecting chip electrode holder. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0034] like Figure 2 and Figure 3 As shown, the present invention provides a rapid testing device for photoconductive antenna chips, including a light source 1, a first test optical path, a second test optical path, a coupling trigger module, a module under test 10, a data acquisition module 11, and a data processing module 13. The module under test 10 is provided with a transmitting chip 16 and a detector chip 17. The first test optical path and the bias voltage excite the transmitting chip 16 to generate a terahertz wave, and the second test optical path and the terahertz wave excite the detector chip 17 to generate an electrical signal. The transmitting chip 16 and the detector chip 17 are rapidly tested by detecting the electrical signal.

[0035] The light source 1 can be a single light source 1 or two independent light sources 1, preferably a dual femtosecond laser with repetitive frequency locking. The dual femtosecond laser can emit two laser beams: laser M and laser S. The repetition frequency of the two laser beams is stably controlled by internal devices of the dual femtosecond laser, and there is a repetition frequency difference Δf between the two laser beams. R The repetition frequency difference is the scanning frequency of the two lasers, which can typically reach tens of kilohertz, and can replace the traditional mechanical delay unit to achieve fast scanning sampling.

[0036] Laser M and laser S enter the first test optical path and the second test optical path, respectively. The first test optical path includes a first coupler 2, a first laser scanning mirror 6, and a first laser lens 8. The second test optical path includes a second coupler 3, a second laser scanning mirror 7, and a second laser lens 9. The first coupler 2 and the second coupler 3 are beam splitters, splitting a laser beam into two beams. The first coupler 2 and the second coupler 3 split and distribute laser M and laser S, respectively. The first coupler 2 splits laser M into laser M1 and laser M2, and the second coupler 3 splits laser S into laser S1 and laser S2. Laser M1 and laser S1 are output to the first laser scanning mirror 6 and the second laser scanning mirror 7, respectively. Laser M2 and laser S2 are output to the coupling trigger module for beam combining.

[0037] The laser scanning galvanometer consists of a pair of laser scanning galvanometers, enabling rapid scanning of the laser within a certain area and controlling its deflection. The first laser lens 8 and the second laser lens 9 are used to focus the laser. The first laser scanning galvanometer 6 deflects laser M1 and, through the first laser lens 8, focuses laser M1 onto the emitting chip 16, exciting the emitting chip 16. The second laser scanning galvanometer 7 deflects laser S1 and, through the second laser lens 9, focuses laser S1 onto the detector chip 17, exciting the detector chip 17. Traditional debugging methods use a multi-dimensional displacement device to adjust the laser lens and chip positions, combined with adjustments to the positions of the hemispherical lens and terahertz lens at the rear end to optimize the terahertz signal. During debugging, each position change requires continuous movement of the traditional optical delay unit to scan the terahertz signal. Laser scanning galvanometers move the laser spot point by point within a certain area of ​​the chip, replacing the debugging process of multi-dimensional displacement devices. Each parameter test during the laser spot movement process can be quickly achieved by sampling with dual femtosecond lasers with repetition frequency locked. The sampling frequency is the difference in repetition frequency between the two laser beams, which can reach tens of kilohertz. This allows for chip testing to be completed in a short time, with a test duration of only a few seconds. This avoids the complex debugging process and enables rapid, pipelined testing of the chip.

[0038] A coupling trigger module is provided between the first test optical path and the second test optical path. This coupling trigger module includes a third coupler 4 and a trigger module 5. The third coupler 4 is a beam-splitting coupler. Laser M2 and laser S2, split by the first coupler 2, are injected into the third coupler 4 and then coupled together before being injected into the trigger module 5. Because there is a repetition frequency difference Δf between laser M2 and laser S2... R When two laser beams are coupled, they form periodic spike signals due to coherence. A signal acquisition threshold is set in the data acquisition module 11. When the spike signal exceeds the threshold, the data acquisition module 11 starts acquiring data. The data acquisition module 11 is communicatively connected to the trigger module 5. A trigger signal is output to one channel of the data acquisition module 11, triggering the acquisition module to start acquiring data.

[0039] The module under test (DUT) 10 includes a mounting bracket 15, in which a transmitter chip 16 and a detector chip 17 are disposed. The transmitter side of the transmitter chip 16 and the detector side of the detector chip 17 are positioned close to each other, with a spacing of 1mm-5mm between them, and are fixed by a mounting fixture. An etalon device 18 is disposed between the transmitter chip 16 and the detector chip 17. This etalon device 18 can be a thin silicon wafer with a thickness ranging from 0.2mm to 0.5mm and high resistivity, exhibiting good surface flatness and parallelism. When the terahertz signal passes through the thin silicon wafer, it is affected by the wafer thickness, refractive index, and absorption coefficient, causing multiple reflection pulses in the time domain, which are used to evaluate the quality of the tested terahertz signal.

[0040] The module under test 10 is mounted on a conveyor device 14, which may be a conveyor belt or the like. Test points are set in the conveyor device 14. A first laser scanning galvanometer 6 and a first laser lens 8 are set on the side where the transmitting chip 16 is located, and a second laser scanning galvanometer 7 and a second laser lens 9 are set on the side where the detector chip 17 is located. The module under test 10 passes through the test points in sequence to test whether the transmitting chip 16 and the detector chip 17 are qualified.

[0041] Through holes are provided on the mounting sides of the transmitting chip 16 and the detecting chip 17 in the mounting bracket 15, as well as at the bottom of the conveyor belt. The laser passes through the through holes and is focused onto the chip under test. Lasers M1 and S1 move point by point to excite the chip via the rotation of the laser scanning galvanometer. After the test is completed, the conveyor device 14 moves the next pair of photoconductive antenna chips to the measurement position to start the next test, realizing the pipeline testing of photoconductive antenna chips.

[0042] The mounting bracket 15 is provided with a transmitter chip electrode holder 19 and a detector chip electrode holder 20. The transmitter chip electrode holder 19 is electrically connected to the bias voltage module 12 and can output a bias voltage to the transmitter chip 16. The detector chip electrode holder 20 is communicatively connected to the data acquisition module 11 and transmits the electrical signals acquired by the detector chip 17.

[0043] The transmitting chip 16 generates a terahertz wave that radiates outward in a divergent manner under the combined action of laser M1 and bias voltage. The installation of a standard etalon device 18 between the transmitting and detecting will cause the terahertz signal to have multiple reflected pulses in the time domain. Laser S1 excites the detection chip 17, and the detection chip 17 generates an electrical signal under the radiation of the terahertz wave and outputs it to the data acquisition module 11.

[0044] The transmitter chip electrode holder 19 and the detector chip electrode holder 20 are movable and can be equipped with retractable electrodes, etc. The electrical input position of the bias voltage and the electrical output position from the detector chip 17 to the data acquisition module 11 can be periodically changed by the transmission device as the detection process progresses.

[0045] Traditional testing methods employ multi-dimensional displacement devices to adjust hemispherical lenses and terahertz lenses for beam transformation, ensuring that most of the energy is incident on the terahertz detection chip 17. However, this patent directly mounts the terahertz emitting chip 16 and the detection chip 17 close together. This allows the terahertz wave to be received by the detection chip 17 as soon as it begins to diverge in space, significantly reducing terahertz energy loss and eliminating the need for complex adjustments to the hemispherical lenses and terahertz lenses used at the terahertz radiating end.

[0046] The data acquisition module 11 includes two channels: a trigger signal channel and an electrical signal acquisition channel. The trigger signal channel acquires the trigger signal generated by the trigger module 5 to control the starting position of the data acquisition module 11. The electrical signal acquisition channel acquires multiple reflected pulse signals obtained from the electrical signal of the detector chip 17. The independent acquisition of data avoids the data processing module 13 from being stuck due to the large amount of data during the acquisition process.

[0047] The data acquisition module 11 is communicatively connected to the data processing module 13. The data processing module 13 is used to control the testing process and process the test results. The data processing module 13 transforms the multiple reflected pulses of the terahertz signal in the time domain into continuous sinusoidal pulses in the frequency domain using Fourier transform. Since the thickness of the etalon is fixed, the period length of the sinusoidal pulses in the frequency domain is also fixed. The number of sinusoidal periods measured in the frequency domain is counted and compared with the expected number of sinusoidal periods that should be measured within the preset minimum acceptable frequency range. By determining whether the number of sinusoidal periods is greater than the expected number, the signal quality of the terahertz pulse is judged. If the number of sinusoidal periods measured in the test frequency domain is not greater than the expected number, meaning that at least one of the tested transmitting chip 16 and detecting chip 17 is defective, the potentially defective transmitting chip 16 and detecting chip 17 are removed, combined with known good chips, and retested to determine which chip has a problem.

[0048] By mounting photoconductive antenna chips in pairs on the transmission device 14, pipeline testing of photoconductive antenna chips can be achieved. This technical solution can complete the testing of a pair of photoconductive antenna chips in just a few seconds, which can greatly improve chip testing efficiency and yield.

[0049] The testing method for photoconductive antenna chips is as follows:

[0050] S1: Two beams with a repetition frequency difference Δf are emitted to the test module 10 mounted at the test position on the transmission device 14. R Laser M and laser S are given. Laser M is split into laser M1 and laser M2, and laser S is split into laser S1 and laser S2.

[0051] S2: The parallel laser M2 and laser S2 form a periodic spike signal due to coherence, which activates the trigger module 5 to generate a trigger signal. The trigger signal triggers the acquisition module to acquire the electrical signal.

[0052] S3: Laser M1 and laser S1 are rapidly scanned and excited by the laser scanning galvanometer and the laser lens. At the same time, a bias voltage is applied to the transmitting chip 16, which emits a terahertz signal. After passing through the etalon device 18, multiple reflection pulses appear in the time domain. The detection chip 17 generates an electrical signal under the radiation of the terahertz wave and outputs it to the data acquisition module 11.

[0053] S4: The trigger signal channel in the data acquisition module 11 acquires the trigger signal generated by the trigger module 5 to control the starting position of the data acquisition module 11. The electrical signal acquisition channel acquires multiple reflected pulse signals obtained from the electrical signal of the detector chip 17.

[0054] S5: The data processing module 13 processes multiple reflected pulse signals, transforms them into continuous sinusoidal pulses in the frequency domain after Fourier transform, counts the number of sinusoidal periods measured in the frequency domain, and determines whether the chip quality in the module under test 10 is qualified by judging whether the number of sinusoidal periods is greater than the expected number.

[0055] S6: The conveying device 14 moves the next module under test 10 to the test point and repeats the above steps.

[0056] S7: Record and filter the modules under test 10 that failed the test, take out the transmitter chip 16 and detector chip 17 that failed the test, and combine the transmitter chip 16 and detector chip 17 that failed the test with the transmitter chip 16 and detector chip 17 that passed the test respectively and retest them to identify the problematic chip.

[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A rapid testing device for photoconductive antenna chips, characterized in that, include: A light source (1) emits laser M and laser S with a locked repetition frequency, wherein there is a repetition frequency difference between laser M and laser S; The first test optical path includes a first coupler (2), a first laser scanning galvanometer (6) and a first laser lens (8). The first coupler (2) splits and distributes the laser M. The laser M is split into laser M1 and laser M2. The laser M1 is output to the first laser scanning galvanometer (6). The first laser scanning galvanometer (6) controls the deflection of the laser beam. The first laser lens (8) focuses the laser. The second test optical path includes a second coupler (3), a second laser scanning galvanometer (7), and a second laser lens (9). The second coupler (3) splits and distributes the laser S, which is divided into laser S1 and laser S2. Laser S1 is output to the second laser scanning galvanometer (7). The second laser scanning galvanometer (7) controls the deflection of the laser beam, and the second laser lens (9) focuses the laser. The coupling trigger module includes a third coupler (4) and a trigger module (5). The third coupler (4) is a parallel beam coupler. The laser M2 and laser S2 are output to the third coupler (4) to generate a parallel beam laser. The trigger module (5) collects the parallel beam laser that generates coherent interaction and generates a trigger signal. The module under test (10) includes a mounting bracket (15), a bias voltage module (12), and a transmitter chip (16) and a detector chip (17) mounted in the mounting bracket (15). The bias voltage module (12) applies a bias voltage to the transmitter chip (16), the laser M1 excites the transmitter chip (16) to generate a terahertz wave, and the laser S1 excites the detector chip (17) to generate an electrical signal under the radiation of the terahertz wave. The data acquisition module (11) receives the trigger signal and the electrical signal from the detection chip (17); The data processing module (13) processes the test results.

2. The rapid testing device for photoconductive antenna chips according to claim 1, characterized in that: The module under test (10) is set on the conveying device (14). The mounting side of the emitting chip (16) and the detector chip (17) in the mounting bracket (15) and the bottom of the conveyor belt are provided with through holes. The laser passes through the through holes and is focused onto the chip under test.

3. The rapid testing device for photoconductive antenna chips according to claim 1, characterized in that: The mounting bracket (15) is provided with a transmitter chip electrode holder (19) and a detector chip electrode holder (20). The transmitter chip electrode holder (19) is electrically connected to the bias voltage module (12), and the detector chip electrode holder (20) is communicatively connected to the data acquisition module (11).

4. The rapid testing device for photoconductive antenna chips according to claim 3, characterized in that: The transmitter chip electrode holder (19) and the detector chip electrode holder (20) are movable. The electrical input position of the bias voltage and the electrical output position of the detector chip (17) to the data acquisition module (11) can be periodically moved by the transmission device as the detection process progresses.

5. The rapid testing device for photoconductive antenna chips according to claim 1, characterized in that: The transmitting chip (16) and the detecting chip (17) are arranged close to each other, with a distance of 1mm-5mm between them. An etalon device (18) is provided between the transmitting chip (16) and the detecting chip (17) to evaluate the quality of the tested terahertz signal.

6. The rapid testing device for photoconductive antenna chips according to claim 5, characterized in that: The data acquisition module (11) includes two channels, namely a trigger signal channel and an electrical signal acquisition channel. The trigger signal channel acquires the trigger signal generated by the trigger module (5) to control the starting position of the data acquisition module (11) acquisition. The electrical signal acquisition channel acquires multiple reflected pulse signals obtained by the electrical signal of the detector chip (17).

7. The rapid testing device for photoconductive antenna chips according to claim 5, characterized in that: The data processing module (13) transforms the multiple reflected pulses of the terahertz signal in the time domain into continuous sinusoidal pulses in the frequency domain through Fourier transform, counts the number of sinusoidal periods measured in the frequency domain, and judges the signal quality of the terahertz pulse.

8. A rapid testing method for a photoconductive antenna chip, characterized in that, include: S1: Two beams with a repetition frequency difference Δf are emitted to the test module (10) mounted on the test position of the transmission device (14). R Laser M and laser S are split into laser M1 and laser M2, and laser S is split into laser S1 and laser S2. S2: The parallel laser M2 and laser S2 form a periodic spike signal due to coherence, which activates the trigger module (5) to generate a trigger signal. The trigger signal triggers the acquisition module to acquire electrical signals. S3: Laser M1 and laser S1 are rapidly scanned and excited by the laser scanning galvanometer and the laser lens. At the same time, a bias voltage is applied to the transmitting chip (16). The transmitting chip (16) emits a terahertz signal, which is reflected multiple times in the time domain by the etalon device (18). The detection chip (17) generates an electrical signal under the radiation of the terahertz wave and outputs it to the data acquisition module (11). S4: The trigger signal channel in the data acquisition module (11) acquires the trigger signal generated by the trigger module (5) to control the starting position of the data acquisition module (11) acquisition, and the electrical signal acquisition channel acquires the multiple reflected pulse signals obtained by the electrical signal of the detector chip (17); S5: The data processing module (13) processes multiple reflected pulse signals, transforms them into continuous sinusoidal pulses in the frequency domain after Fourier transformation, counts the number of sinusoidal periods measured in the frequency domain, and judges whether the chip quality in the module under test (10) is qualified by determining whether the number of sinusoidal periods is greater than the expected number. S6: The conveying device (14) moves the next module under test (10) to the test point and repeats the above steps; S7: Record and filter the modules under test (10) that failed the test, take out the transmitter chip (16) and detector chip (17) that failed the test, and combine the transmitter chip (16) and detector chip (17) that failed the test with the transmitter chip (16) and detector chip (17) that passed the test respectively and retest to identify the problematic chip.

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