A testing system and method for a photodetector chip

Abstract

The application discloses a photoelectric detection chip testing system and method. The system comprises a light source assembly, a power supply assembly, a fiber assembly, a conversion assembly, a coupling assembly and a testing assembly. The light source assembly is used for providing a test light signal. The power supply assembly provides a bias voltage for a to-be-tested photoelectric detection chip. The fiber assembly is used for receiving the test light signal and transmitting the test light signal to the to-be-tested photoelectric detection chip. The conversion assembly is used for receiving a photoelectric current signal output by the to-be-tested photoelectric detection chip, converting the photoelectric current signal into a voltage signal and providing the voltage signal to the coupling assembly. The coupling assembly is used for controlling the fiber assembly to move based on the voltage signal provided by the conversion assembly, so that the to-be-tested photoelectric detection chip is coupled to the most test light signals. The testing assembly is used for testing the performance of the to-be-tested photoelectric detection chip in the case that the to-be-tested photoelectric detection chip is coupled to the most test light signals.

Description

Technical Field

[0001] This invention relates to the field of testing optoelectronic integrated chips and devices, and more particularly to a testing system and method for photoelectric detection chips. Background Technology

[0002] Optoelectronic detection chips are sensors that convert light radiation signals into electrical signals using materials with photoelectric effects. The greater the light intensity, the greater the photocurrent; in the absence of light, they are almost insulators. They are currently widely used in various fields such as industrial automation, smart wearables, missile guidance, optical measurement and detection, flame detection, and communications. Currently, the coupling process in the testing phase of optoelectronic detection chips cannot be directly and automatically coupled. For the mass production of optoelectronic detection chips, there is an urgent need for a fast, directly coupled testing system for use in the testing phase. Summary of the Invention

[0003] In view of this, the main objective of the present invention is to provide a testing system and method for photoelectric detection chips, which can directly realize automatic coupling in the testing stage of photoelectric detection chips, and has a low cost for modifying existing testing systems, and can realize wafer-level automated testing of photoelectric detection chips.

[0004] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0005] In a first aspect, the present invention provides a testing system for a photoelectric detection chip, the system comprising a light source assembly, a power supply assembly, an optical fiber assembly, a conversion assembly, a coupling assembly, and a testing assembly, wherein;

[0006] The light source assembly is used to provide test light signals; the power supply assembly provides bias voltage to the photodetector chip under test.

[0007] The optical fiber assembly is used to receive the test optical signal and transmit the test optical signal to the photoelectric detector chip under test.

[0008] The conversion component is used to receive the photocurrent signal output by the photodetector chip under test, convert the photocurrent signal into a voltage signal, and provide the voltage signal to the coupling component; the photocurrent signal is obtained by the photodetector chip under test based on the received test light signal and the bias voltage;

[0009] The coupling component is used to control the movement of the optical fiber component based on the voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the maximum amount of the test optical signal.

[0010] The test component is used to test the performance of the photodetector chip under test when the photodetector chip under test is coupled to the maximum amount of the test optical signal.

[0011] In the above scheme, when the optical fiber assembly includes a first optical fiber that is a polarization-maintaining fiber, one end of the first optical fiber is connected to the light source assembly to receive the test optical signal;

[0012] Correspondingly, the coupling component is specifically used to: control the other end of the first optical fiber to move based on the voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the maximum amount of the test optical signal transmitted through the first optical fiber.

[0013] In the above scheme, the system further includes: a polarization controller, connected to the other end of the first optical fiber, for receiving the test optical signal transmitted by the first optical fiber, and adjusting the polarization controller so that the test optical signal meets the polarization conditions.

[0014] In the above scheme, the optical fiber assembly further includes a second optical fiber, one end of which is connected to the polarization controller; used to receive the test optical signal that meets the polarization conditions output by the polarization controller, and transmit the test optical signal to the photodetector chip under test;

[0015] Correspondingly, the coupling component is further configured to: before adjusting the polarization controller, control the other end of the second optical fiber to move based on a first voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the second optical fiber to transmit the test optical signal that has not been adjusted by the polarization controller; and after adjusting the polarization controller, control the other end of the second optical fiber to move based on a second voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the second optical fiber to transmit the test optical signal that meets the polarization conditions.

[0016] Wherein, the first voltage signal is obtained by the conversion component based on the first photocurrent signal; the second voltage signal is obtained by the conversion component based on the second photocurrent signal; the first photocurrent is the current signal output by the photodetector chip under test based on the test light signal that has not been adjusted by the polarization controller; and the second photocurrent is the current signal output by the photodetector chip under test based on the test light signal that meets the polarization conditions.

[0017] In the above scheme, the conversion component is a resistor module, and the photocurrent signal output by the photodetector chip under test is obtained through a DC probe.

[0018] In the above scheme, the resistor module is a parallel resistor or a parallel transimpedance amplifier.

[0019] In the above scheme, the coupling method used in the coupling component is at least one of the following: spiral method, hill climbing method, and simulated annealing method.

[0020] Secondly, the present invention also provides a testing method for a photoelectric detection chip, applied to a testing system for the photoelectric detection chip, the system comprising a light source component, a power supply component, an optical fiber component, a conversion component, a coupling component, and a testing component; the method comprising:

[0021] The light source assembly provides the test light signal; the power supply assembly provides the bias voltage to the photoelectric detection chip under test.

[0022] The optical fiber assembly receives the test optical signal and transmits the test optical signal to the photoelectric detector chip under test;

[0023] The conversion component receives the photocurrent signal output by the photodetector chip under test, converts the photocurrent signal into a voltage signal, and provides the voltage signal to the coupling component; the photocurrent signal is obtained by the photodetector chip under test based on the received test light signal and the bias voltage;

[0024] The coupling component controls the movement of the optical fiber component based on the voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the maximum amount of the test optical signal;

[0025] The test component tests the performance of the photodetector chip under test when the chip is coupled to the maximum amount of the test light signal.

[0026] In the above scheme, when the optical fiber assembly includes a first optical fiber that is a polarization-maintaining fiber, one end of the first optical fiber is connected to the light source assembly to receive the test optical signal;

[0027] Correspondingly, the coupling component controls the other end of the first optical fiber to move based on the voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the maximum amount of the test optical signal transmitted through the first optical fiber.

[0028] In the above scheme, the system further includes: a polarization controller, connected to the other end of the first optical fiber, for receiving the test optical signal transmitted by the first optical fiber, and adjusting the polarization controller so that the test optical signal meets the polarization conditions.

[0029] In the above scheme, the optical fiber assembly further includes a second optical fiber, one end of which is connected to the polarization controller; it receives the test optical signal that meets the polarization conditions output by the polarization controller and transmits the test optical signal to the photodetector chip under test;

[0030] Correspondingly, before adjusting the polarization controller, the coupling component controls the other end of the second optical fiber to move based on a first voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the second optical fiber to transmit the test optical signal that has not been adjusted by the polarization controller; and after adjusting the polarization controller, the coupling component controls the other end of the second optical fiber to move based on a second voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the second optical fiber to transmit the test optical signal that meets the polarization conditions.

[0031] Wherein, the first voltage signal is obtained by the conversion component based on the first photocurrent signal; the second voltage signal is obtained by the conversion component based on the second photocurrent signal; the first photocurrent is the current signal output by the photodetector chip under test based on the test light signal that has not been adjusted by the polarization controller; and the second photocurrent is the current signal output by the photodetector chip under test based on the test light signal that meets the polarization conditions.

[0032] This invention provides a testing system and method for a photodetector chip. The system includes a light source component, a power supply component, an optical fiber component, a conversion component, a coupling component, and a testing component. The light source component provides a test optical signal. The power supply component provides a bias voltage to the photodetector chip under test. The optical fiber component receives the test optical signal and transmits it to the photodetector chip. The conversion component receives a photocurrent signal output by the photodetector chip, converts it into a voltage signal, and provides the voltage signal to the coupling component. The photocurrent signal is obtained by the photodetector chip based on the received test optical signal and the bias voltage. The coupling component controls the movement of the optical fiber component based on the voltage signal provided by the conversion component, so that the photodetector chip is coupled with the maximum amount of test optical signal. The testing component tests the performance of the photodetector chip under test when it is coupled with the maximum amount of test optical signal. The testing system and method for photoelectric detector chips provided in this invention are not only simple to set up and highly efficient, but also highly automated, making them suitable for mass production testing. Furthermore, by converting the current signal output by the photoelectric detector chip into a voltage signal using a parallel resistor, existing coupling systems that achieve automatic coupling via voltage signals can be directly used, resulting in low modification costs and facilitating commercialization. This testing system enables automated testing of photoelectric detector chips at the wafer level. Attached Figure Description

[0033] Figure 1 A schematic diagram of the structure of a test system for a photoelectric detection chip provided in an embodiment of the present invention;

[0034] Figure 2 A schematic diagram illustrating the working principle of a test system for a photoelectric detection chip including a polarization controller, provided in an embodiment of the present invention.

[0035] Figure 3 Provided for embodiments of the present invention Figure 2 A flowchart illustrating the workflow of the testing system in the document;

[0036] Figure 4 This is a flowchart illustrating the testing method for the photoelectric detection chip provided in an embodiment of the present invention. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the specific technical solutions of the invention will be further described in detail below with reference to the accompanying drawings of the embodiments of the present invention. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0038] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0039] Figure 1 This is a schematic diagram of a test system for a photoelectric detection chip provided in an embodiment of the present invention. Figure 1 In the system 10, the system includes: a light source assembly 101, a power supply assembly 102, an optical fiber assembly 103, a conversion assembly 104, a coupling assembly 105, and a testing assembly 106, wherein;

[0040] The light source assembly 101 is used to provide test light signals; the power supply assembly 102 provides bias voltage to the photoelectric detection chip under test.

[0041] The optical fiber assembly 103 is used to receive the test optical signal and transmit the test optical signal to the photoelectric detector chip under test.

[0042] The conversion component 104 is used to receive the photocurrent signal output by the photodetector chip under test, convert the photocurrent signal into a voltage signal, and provide the voltage signal to the coupling component 105; the photocurrent signal is obtained by the photodetector chip under test based on the received test light signal and the bias voltage.

[0043] The coupling component 105 is used to control the movement of the optical fiber component 103 based on the voltage signal provided by the conversion component 104, so that the photodetector chip under test is coupled to the maximum amount of the test optical signal.

[0044] The test component 106 is used to test the performance of the photodetector chip under test when the photodetector chip under test is coupled to the maximum amount of the test optical signal.

[0045] It should be noted that this test system is built for testing photodetector chips. The light source component 101 is related to the type of photodetector chip under test. When the photodetector chip under test is an ultraviolet photodetector chip, an ultraviolet LED light source is used; when the photodetector chip under test is an infrared photodetector chip, an infrared LED light source is used. Regardless of the light source, its specific structure may include: a ring-shaped base and an ultraviolet LED or infrared LED placed on the ring-shaped base, etc. The power supply component 102 provides a stable bias voltage to the photodetector chip under test, for example, a stable bias voltage of 5 volts (V).

[0046] In some embodiments, when the optical fiber assembly includes a first optical fiber that is a polarization-maintaining fiber, one end of the first optical fiber is connected to the light source assembly for receiving the test optical signal;

[0047] Correspondingly, the coupling component is specifically used to: control the other end of the first optical fiber to move based on the voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the maximum amount of the test optical signal transmitted through the first optical fiber.

[0048] In practical applications, the first optical fiber is a polarization-maintaining fiber to ensure that the polarization of the test light signal emitted by the light source component remains unchanged. When only the first optical fiber is present, the coupling component needs to control the movement of the other end of the first optical fiber to couple the photodetector chip under test to the maximum amount of the test light signal transmitted from the first optical fiber.

[0049] In other embodiments, the system further includes a polarization controller connected to the other end of the first optical fiber, for receiving the test optical signal transmitted through the first optical fiber and adjusting the polarization controller so that the test optical signal meets polarization conditions.

[0050] Here, the polarization controller can be an on-chip integrated polarization controller, a passive discrete polarization controller, an instrument polarization controller, etc., and its material can be a polymer composed of elements such as silicon dioxide, silicon nitride, silicon, group III-V, and germanium. The polarization condition mentioned by the polarization controller can refer to obtaining a test optical signal with maximum optical power. In one feasible embodiment, when the polarization controller can be composed of waveplates of λ / 4, λ / 2, and λ / 4, a test optical signal satisfying the polarization condition can be obtained by rotating the waveplates. Here, λ is the wavelength of the test optical signal.

[0051] Based on the aforementioned system, in some embodiments, the optical fiber assembly further includes a second optical fiber, one end of which is connected to the polarization controller; used to receive the test optical signal output by the polarization controller that meets the polarization conditions, and to transmit the test optical signal to the photodetector chip under test;

[0052] Correspondingly, the coupling component is further configured to: before adjusting the polarization controller, control the other end of the second optical fiber to move based on a first voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the second optical fiber to transmit the test optical signal that has not been adjusted by the polarization controller; and after adjusting the polarization controller, control the other end of the second optical fiber to move based on a second voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the second optical fiber to transmit the test optical signal that meets the polarization conditions.

[0053] Wherein, the first voltage signal is obtained by the conversion component based on the first photocurrent signal; the second voltage signal is obtained by the conversion component based on the second photocurrent signal; the first photocurrent is the current signal output by the photodetector chip under test based on the test light signal that has not been adjusted by the polarization controller; and the second photocurrent is the current signal output by the photodetector chip under test based on the test light signal that meets the polarization conditions.

[0054] This describes a coupling operation performed both before and after adjusting the polarization controller. The initial coupling operation uses a test light signal that has not been adjusted by the polarization controller, which can also be understood as a test light signal that does not meet the polarization conditions. The subsequent coupling operation uses a test light signal adjusted by the polarization controller, i.e., a test light signal that meets the polarization conditions. The specific coupling process is described below. In some embodiments, the coupling component 105 employs at least one of the following coupling methods: spiral coupling, hill-climbing coupling, and simulated annealing coupling.

[0055] In some embodiments, the conversion component 104 can be a resistor module that obtains the photocurrent signal output by the photodetector chip under test via a DC probe. In some embodiments, the resistor module can be a parallel resistor or a parallel transimpedance amplifier as the conversion component 104. For example, in some embodiments, the parallel resistor can be composed of two 100-ohm resistors connected in parallel. The specific function of the conversion component 104 can be: receiving the photocurrent signal output by the photodetector chip under test, converting the photocurrent signal into a voltage signal, and providing the voltage signal to the coupling component 105; the photocurrent signal can be obtained by the photodetector chip under test based on the received test light signal and the bias voltage.

[0056] The aforementioned testing of the performance of the photodetector chip under test can refer to testing its current-voltage (V / V) characteristics. These V / V characteristics can refer to the relationship between the bias voltage and photocurrent of the photodetector chip under test, or the relationship between the bias voltage and dark current. The specific testing process can involve scanning the bias voltage within a certain range, such as from -2V to 3V, according to the design specifications of the photodetector. The scanning step size can be determined based on the actual situation. The bias voltage corresponds one-to-one with the photocurrent or dark current, thereby obtaining the photocurrent V / V characteristic curve and / or dark current V / V characteristic curve. Testing the performance of the photodetector chip under test can also refer to testing its radio frequency (RF) performance, which can include parameters such as bandwidth. This can be specifically tested using an optical component analyzer. Finally, testing the performance of the photodetector chip under test can also refer to testing its responsivity. The responsivity can be the ratio of the photocurrent output by the photodetector chip under test to the aforementioned photopower when the light source component emits a fixed light power and the power supply component provides a fixed bias voltage.

[0057] To understand the present invention, as Figure 2 The diagram illustrates the working principle structure of a test system for a photoelectric detection chip including a polarization controller, provided in an embodiment of the present invention. Figure 3 As shown, it illustrates the embodiment of the present invention. Figure 2 The diagram illustrates the workflow of the testing system. It should be noted that test component 106... Figure 2 Not shown in the image.

[0058] The following is in conjunction with the appendix Figure 1 Appendix Figure 2 and attached Figure 3 The working principle of the test system for the photoelectric detection chip provided in the embodiments of the present invention is introduced.

[0059] Specifically, such as Figure 2As shown, the light source assembly 101 can provide a test optical signal with a fixed wavelength (preferably 1550 nanometers (nm) for the C-band) and power; the power supply assembly 102 provides a stable bias voltage to the photodetector chip under test (PDT) to enable it to operate normally. After this, two couplings and one polarization adjustment are required. The first coupling is performed before adjusting the polarization controller. In this coupling, the light source assembly provides a test optical signal of a certain wavelength within the operating wavelength range. The coupling assembly controls the other end of the second optical fiber to move to a position where the PDT can receive the maximum amount of that specific wavelength of test optical signal; this position is only approximate. The second coupling is performed after adjusting the polarization controller. The light source assembly provides a test optical signal that meets the polarization conditions. The wavelength of this test optical signal is the optimal wavelength for the PDT to operate at. Under this optimal wavelength test optical signal, the coupling assembly controls the other end of the second optical fiber to move to a position where the PDT can receive the maximum amount of that optimal wavelength of test optical signal. The polarization adjustment involves adjusting the aforementioned polarization controller to achieve the optimal polarization state of the test optical signal to obtain the aforementioned optimal wavelength test optical signal. In summary, the first and second coupling processes are identical, both involving the control of the second optical fiber. The first coupling is used to move the fiber to a better position. Then, the polarization controller is adjusted to maximize the voltage, and the entire wavelength range is scanned. For example, in the C-band, the wavelength of the test light signal emitted by the light source component ranges from 1530nm to 1565nm until the wavelength corresponding to the voltage is found; this wavelength is the optimal wavelength. Subsequently, the second optical fiber is controlled for a second coupling, as the optimal coupling position may differ for different wavelengths. It should be noted that the execution order of the aforementioned three processes can be: first coupling, polarization adjustment, and second coupling.

[0060] Specifically, the first coupling process can be as follows: When the light source component and the power supply component are closed and in the working state, the coupling component 105 calls its stored coupling control program to perform the first automatic coupling. The specific process includes: firstly, using the spiral method for coarse coupling, and then using the simulated annealing method for fine coupling. The spiral method can refer to randomly selecting a point O1 in the photosensitive area of ​​the photodetector chip under test, using O1 as the center and radius R1, controlling the first optical fiber to rotate in the XY plane to obtain the point O2 where the coupling component receives the maximum voltage signal. Then, using O2 as the center and radius R2 (R2 is less than R1), controlling the first optical fiber to rotate in the XY plane to obtain the point O3 where the coupling component receives the maximum voltage signal. This process is repeated until the minimum controllable accuracy of coarse coupling is reached, and the point O where the coupling component receives the maximum voltage signal is obtained, thus completing the coarse coupling. The simulated annealing method can be as follows: Let the initial temperature be T, the rate of temperature change be ΔT, and the initial point be P. The voltage signal received by the corresponding coupling component is V0. Randomly move the optical fiber to P1, where the voltage signal received by the corresponding coupling component is V1. If V1 is greater than V0, then accept P1. Otherwise, proceed with the process with probability e. ((V1-V0) / T) The process continues until P1 is received, and the voltage signal received by the coupling component reaches its maximum when T approaches 0. At this point, the other end of the second optical fiber is stopped, and the second optical fiber is fixed in that position. It should be understood that, based on the aforementioned schematic diagram of the test system 10, since the conversion component has resistive properties, the photocurrent signal output by the photodetector chip under test is positively correlated with the voltage signal. Therefore, when the aforementioned voltage signal is at its maximum, the photocurrent signal output by the photodetector chip under test is also at its maximum. At this time, the test light signal emitted by the light source component coupled to the maximum extent in the first optical fiber is at this point. Here, the XY plane refers to a plane parallel to the ground.

[0061] In some embodiments, the polarization controller can be composed of waveplates with wavelengths of λ / 4, λ / 2, and λ / 4. By rotating the waveplates, the desired polarized light, i.e., the polarized light signal that meets the set conditions, can be obtained. In practical applications, after the first optical fiber is fixed, only the polarization controller is adjusted, and the waveplate position of the polarization controller is recorded when the photocurrent signal output by the photodetector is at its maximum. At this point, the polarized light signal output by the polarization controller meets the set conditions. Here, λ is the wavelength of the test light signal.

[0062] Then, a second coupling is performed, which is the coupling between the second optical fiber and the photodetector chip under test. The specific process is similar to the first coupling, and its specific process will not be described in detail here.

[0063] After completing the aforementioned three adjustment processes, the photoelectric detection chip is tested. Subsequently, the photoelectric detection chips are tested in large quantities following the same three adjustment processes. For the same batch of photoelectric detection chips of the same type, the aforementioned polarization controller only needs to be adjusted once.

[0064] The photoelectric detector chip testing system provided in this invention is not only simple to set up and highly efficient, but also highly automated, making it suitable for mass production testing. Furthermore, by converting the current signal output by the photoelectric detector chip into a voltage signal using a parallel resistor, it can directly utilize existing coupling systems that achieve automatic coupling via voltage signals, resulting in low modification costs and facilitating commercialization. This testing system enables automated testing of photoelectric detector chips at the wafer level.

[0065] Based on the same inventive concept, embodiments of the present invention also provide a testing method for a photoelectric detection chip. Figure 4 The diagram shown illustrates a flowchart of a testing method for a photoelectric detection chip provided in an embodiment of the present invention. Figure 4 In this context, the method is applied to a testing system for the photoelectric detection chip, the system comprising a light source assembly, a power supply assembly, an optical fiber assembly, a conversion assembly, a coupling assembly, and a testing assembly; specifically, the method may include:

[0066] S101: The light source assembly provides a test light signal; the power supply assembly provides a bias voltage to the photodetector chip under test;

[0067] S102: The optical fiber assembly receives the test optical signal and transmits the test optical signal to the photoelectric detection chip under test;

[0068] S103: The conversion component receives the photocurrent signal output by the photodetector chip under test, converts the photocurrent signal into a voltage signal, and provides the voltage signal to the coupling component; the photocurrent signal is obtained by the photodetector chip under test based on the received test light signal and the bias voltage;

[0069] S104: The coupling component controls the movement of the optical fiber component based on the voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the maximum amount of the test optical signal;

[0070] S105: The test component tests the performance of the photodetector chip under test when the photodetector chip under test is coupled to the maximum amount of the test light signal.

[0071] In some embodiments, when the optical fiber assembly includes a first optical fiber that is a polarization-maintaining fiber, one end of the first optical fiber is connected to the light source assembly to receive the test optical signal;

[0072] Correspondingly, the coupling component controls the other end of the first optical fiber to move based on the voltage signal provided by the conversion component, so that the photodetector chip under test is coupled to the maximum amount of the test optical signal transmitted through the first optical fiber.

[0073] In some embodiments, the system further includes: a polarization controller connected to the other end of the first optical fiber, for receiving the test optical signal transmitted through the first optical fiber, and adjusting the polarization controller so that the test optical signal meets polarization conditions.

[0074] In some embodiments, the optical fiber assembly further includes a second optical fiber, one end of which is connected to the polarization controller; it receives the test optical signal that meets the polarization conditions output by the polarization controller and transmits the test optical signal to the photodetector chip under test;

[0075] Correspondingly, before adjusting the polarization controller, the coupling component controls the other end of the second optical fiber to move based on a first voltage signal provided by the conversion component, so that the photodetector chip under test couples to the second optical fiber with the maximum amount of test optical signals that have not been adjusted by the polarization controller; and after adjusting the polarization controller, it controls the other end of the second optical fiber to move based on a second voltage signal provided by the conversion component, so that the photodetector chip under test couples to the second optical fiber with the maximum amount of test optical signals that meet the polarization conditions; wherein, the first voltage signal is obtained by the conversion component based on a first photocurrent signal; the second voltage signal is obtained by the conversion component based on a second photocurrent signal; the first photocurrent is the current signal output by the photodetector chip under test based on the test optical signals that have not been adjusted by the polarization controller; and the second photocurrent is the current signal output by the photodetector chip under test based on the test optical signals that meet the polarization conditions.

[0076] The testing method for the photoelectric detection chip provided in this embodiment of the invention and the testing system for the photoelectric detection chip provided in this embodiment of the invention belong to the same inventive concept. Therefore, the terms used herein have been described in detail above and will not be repeated here.

[0077] In the several embodiments provided by this invention, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms. The units described above as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units; some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs. In addition, all functional units in the various embodiments of this invention can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the integrated unit can be implemented in hardware or in the form of hardware plus software functional units.

[0078] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention.

Claims

1. A testing system of a photodetection chip, characterized in that, The system comprises a light source assembly, a power supply assembly, a polarization controller, a fiber assembly, a conversion assembly, a coupling assembly and a test assembly, wherein The light source assembly is configured to provide a test light signal; The power supply assembly is configured to provide a bias voltage for the to-be-tested photodetector chip; The polarization controller is configured to make the test light signal satisfy a polarization condition, and the polarization condition is maximum optical power; The fiber assembly comprises a first fiber which is a polarization maintaining fiber, one end of the first fiber is connected with the light source assembly and configured to receive the test light signal, and the other end of the first fiber is connected with the polarization controller and configured to transmit the test light signal to the polarization controller; The fiber assembly further comprises a second fiber, one end of the second fiber is connected with the polarization controller and configured to receive the test light signal output by the polarization controller and satisfying the polarization condition, and transmit the test light signal to the to-be-tested photodetector chip; The conversion assembly is configured to receive a photocurrent signal output by the to-be-tested photodetector chip, convert the photocurrent signal into a voltage signal, and provide the voltage signal to the coupling assembly; The photocurrent signal is obtained by the to-be-tested photodetector chip based on the received test light signal and the bias voltage; The coupling assembly is configured to control the movement of the other end of the first fiber based on the voltage signal provided by the conversion assembly, so that the to-be-tested photodetector chip is coupled to the most test light signal transmitted by the first fiber; The coupling assembly is further configured to control the movement of the other end of the second fiber based on a first voltage signal provided by the conversion assembly before adjusting the polarization controller, so that the to-be-tested photodetector chip is coupled to the most test light signal transmitted by the second fiber and not adjusted by the polarization controller; And control the movement of the other end of the second fiber based on a second voltage signal provided by the conversion assembly after adjusting the polarization controller, so that the to-be-tested photodetector chip is coupled to the most test light signal satisfying the polarization condition transmitted by the second fiber; The first voltage signal is obtained by the conversion assembly based on a first photocurrent signal, and the second voltage signal is obtained by the conversion assembly based on a second photocurrent signal, the first photocurrent is a current signal output by the to-be-tested photodetector chip based on the test light signal not adjusted by the polarization controller, and the second photocurrent is a current signal output by the to-be-tested photodetector chip based on the test light signal satisfying the polarization condition; The test assembly is configured to test the performance of the to-be-tested photodetector chip when the to-be-tested photodetector chip is coupled to the most test light signal.

2. The system of claim 1, wherein, The conversion assembly is a resistance module, and the photocurrent signal output by the to-be-tested photodetector chip is obtained through a direct current probe.

3. The system of claim 2, wherein, The resistance module is a parallel resistance or a parallel trans-impedance amplifier.

4. The system according to any one of claims 1 to 3, characterized in that, The coupling assembly adopts at least one of the following coupling modes: a spiral mode, a mountain climbing mode and an analog annealing mode.

5. A method of testing a photodetection chip, the method comprising: applying a test signal to the photodetection chip; and measuring a response of the photodetection chip to the test signal. The application is applied to a test system of the photoelectric detection chip, and the system comprises a light source assembly, a power supply assembly, a polarization controller, a fiber assembly, a conversion assembly, a coupling assembly and a test assembly. The light source assembly provides a test light signal; the power supply assembly provides a bias voltage for the photoelectric detection chip to be tested; the polarization controller makes the test light signal meet a polarization condition, and the polarization condition is that the optical power is maximum. The fiber assembly comprises a first fiber which is a polarization maintaining fiber, one end of the first fiber is connected with the light source assembly to receive the test light signal, and the other end of the first fiber is connected with the polarization controller to transmit the test light signal to the polarization controller. The fiber assembly further comprises a second fiber, one end of the second fiber is connected with the polarization controller to receive the test light signal meeting the polarization condition output by the polarization controller and transmit the test light signal to the photoelectric detection chip to be tested. The conversion assembly receives a photoelectric current signal output by the photoelectric detection chip to be tested, converts the photoelectric current signal into a voltage signal, and provides the voltage signal to the coupling assembly; the photoelectric current signal is obtained by the photoelectric detection chip to be tested based on the received test light signal and the bias voltage; The coupling assembly controls the movement of the other end of the first fiber based on the voltage signal provided by the conversion assembly, so that the photoelectric detection chip to be tested is coupled to the most test light signals transmitted by the first fiber; before adjusting the polarization controller, the coupling assembly controls the movement of the other end of the second fiber based on the first voltage signal provided by the conversion assembly, so that the photoelectric detection chip to be tested is coupled to the most test light signals transmitted by the second fiber without adjustment of the polarization controller; and after adjusting the polarization controller, the coupling assembly controls the movement of the other end of the second fiber based on the second voltage signal provided by the conversion assembly, so that the photoelectric detection chip to be tested is coupled to the most test light signals meeting the polarization condition transmitted by the second fiber; The first voltage signal is obtained by the conversion assembly based on a first photoelectric current signal; the second voltage signal is obtained by the conversion assembly based on a second photoelectric current signal; the first photoelectric current is a current signal output by the photoelectric detection chip to be tested based on the test light signal without adjustment of the polarization controller; and the second photoelectric current is a current signal output by the photoelectric detection chip to be tested based on the test light signal meeting the polarization condition; The test assembly tests the performance of the photoelectric detection chip to be tested when the photoelectric detection chip to be tested is coupled to the most test light signals.

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