Testing device of silicon-based photoelectric integrated chip, silicon-based photoelectric integrated chip and testing method of silicon-based photoelectric integrated chip

Abstract

The embodiment of the invention provides a testing device of a silicon-based photoelectric integrated chip, the silicon-based photoelectric integrated chip and a testing method of the silicon-based photoelectric integrated chip, and belongs to the technical field of chip testing. The test device comprises a tunable polarization-maintaining light source configured to output polarization-maintaining light; the first optical coupling link comprises a first polarization-maintaining optical splitter allowing polarization-maintaining light to pass through, an optical power meter, a single-channel array and an input port of a silicon-based photoelectric integrated chip; the second optical coupling link comprises a second polarization-maintaining optical splitter allowing polarization-maintaining light to pass through, at least two polarization-maintaining optical circulators, an optical power meter, a multi-channel array and at least two polarization-maintaining light output ports of a silicon-based photoelectric integrated chip; and the 1 * 2 polarization-maintaining optical switch is configured to switch polarization-maintaining light between the first optical coupling link and the second optical coupling link. According to the testing device, time domain multiplexing of optical path coupling and parameter measurement in the same optical path system is achieved, and alignment of a chip port and an optical fiber array and evaluation of chip performance parameters are completed at a time.

Description

Technical Field

[0001] The present invention belongs to the technical field of chip testing, and in particular relates to a testing device for a silicon-based optoelectronic integrated chip, a silicon-based optoelectronic integrated chip and a testing method thereof. Background Art

[0002] Silicon-based photonics integrated circuit (PIC) is an integrated chip formed by monolithically integrating several basic devices such as light emitting integrated chip, light receiving integrated chip, light transceiver integrated chip, and array integrated chip of devices with the same function (detector array chip, modulator array chip).

[0003] Compared with traditional optical devices, PIC chips have the advantages of small size, fast response speed, low power consumption, high integration and low cost. They are important optical components in the fields of optical communication, optical interconnection, optical computing, etc., and are widely used in advanced fields such as data centers, cloud computing, 5G / 6G communications, and autonomous driving. With the rapid development of new technologies such as artificial intelligence and the Internet of Things, the market demand for PIC chips has further expanded. The number of array channels integrated in PIC chips is proportional to the communication transmission rate. As the communication transmission rate develops from 100Gbps to 400Gbps, 800Gbps and 1.6Tbps, the number of channels in PIC chips has also expanded from single channel to 4 channels and 8 channels. There are also more and more monolithic integrated silicon optical devices, which brings great challenges to the evaluation of PIC chips.

[0004] The current evaluation method is to establish an optical coupling system and a measurement system separately. As the number of channels increases, the input and output ends of the PIC chip need to be optically coupled separately; as the integration level increases, different measurement systems need to be established for different parameters. This further increases the complexity of the evaluation system. If the above method is still used, it will not be able to meet the mass production and manufacturing needs of PIC chips.

[0005] In view of this, it is indeed necessary to provide a new type of PIC chip testing device, PIC chip and testing method thereof. Summary of the invention

[0006] In order to solve at least one aspect of the above problems and defects in the prior art, the embodiments of the present invention provide a test device for a silicon-based optoelectronic integrated chip, a silicon-based optoelectronic integrated chip and a test method thereof, which multiplexes the coupling optical path and the measurement optical path in the time domain, thereby achieving the coupling alignment between the silicon-based optoelectronic integrated chip port and the optical fiber channel array and the evaluation of the performance parameters of the silicon-based optoelectronic integrated chip in one optical link at one time. The technical solution is as follows:

[0007] According to one aspect of the present invention, a testing device for a silicon-based optoelectronic integrated chip is provided, the testing device comprising:

[0008] A tunable polarization-maintaining light source, configured to output polarization-maintaining light;

[0009] A first optical coupling link includes a first polarization-maintaining optical splitter that allows the polarization-maintaining light to pass through, a single-channel array, and an input port of a silicon-based optoelectronic integrated chip;

[0010] The second optical coupling link includes a second polarization-maintaining optical splitter that allows the polarization-maintaining light to pass through, at least two polarization-maintaining optical circulators, a multi-channel array, and at least two polarization-maintaining optical output ports of a silicon-based optoelectronic integrated chip;

[0011] The 1×2-way polarization-maintaining optical switch is configured to switch the polarization-maintaining light between the first optical coupling link and the second optical coupling link.

[0012] Furthermore, the test device also includes an optical parameter measurement link formed by time domain multiplexing of the first optical coupling link and the second optical coupling link; in the optical parameter measurement link, the polarization-maintaining light is sequentially input to the input port of the silicon-based optoelectronic integrated chip through the 1×2 polarization-maintaining optical switch, the first polarization-maintaining optical splitter and the single-channel array; thereafter, the polarization-maintaining light is output from all output ports of the silicon-based optoelectronic integrated chip to the corresponding channels of the multi-channel optical power meter.

[0013] In some embodiments, the number of output ports of the first polarization-maintaining optical splitter and the second polarization-maintaining optical splitter is at least two; when the number of output ports of the first polarization-maintaining optical splitter and the second polarization-maintaining optical splitter is two, and the number of all output ports of the silicon-based optoelectronic integrated chip is N, then:

[0014] The at least two polarization-maintaining circulators are two in number and include a first polarization-maintaining circulator and a second polarization-maintaining circulator;

[0015] The number of channels of the multi-channel array is N, and corresponds one-to-one to the N output ports of the silicon-based optoelectronic integrated chip, where N is an integer;

[0016] The two outermost output ports of the N output ports of the silicon-based optoelectronic integrated chip are respectively set as the first polarization-maintaining light receiving port and the second polarization-maintaining light receiving port, and the remaining N-2 output ports are other polarization-maintaining light output ports;

[0017] The number of channels of a multi-channel optical power meter is N+2.

[0018] Furthermore, among the N+2 channels of the multi-channel optical power meter, channel 1 is configured to receive one of the polarization-maintaining lights output by the first polarization-maintaining light splitter; the N channels from channel 2 to channel N+1 are configured to correspondingly receive output lights of the N output ports of the silicon-based optoelectronic integrated chip; and channel N+2 is configured to receive the other polarization-maintaining light output by the first polarization-maintaining light splitter.

[0019] In some embodiments, a first polarization-maintaining circulator includes a first port, a second port, and a third port; wherein light input through the first port can only be output through the second port; light input through the second port can only be output through the third port; one of the polarization-maintaining lights output by the second polarization-maintaining light splitter enters the first port of the first polarization-maintaining circulator and then passes through the second port and the corresponding channel of the multi-channel array to enter the first polarization-maintaining light receiving port of the silicon-based optoelectronic integrated chip; the polarization-maintaining light output from the first polarization-maintaining light receiving port of the silicon-based optoelectronic integrated chip passes through the corresponding channel of the multi-channel array to enter the second port of the first polarization-maintaining circulator and is output from the third port to the corresponding channel of the multi-channel optical power meter.

[0020] In some embodiments, the second polarization-maintaining circulator includes a fourth port, a fifth port and a sixth port; wherein light input through the fourth port can only be output through the fifth port; light input through the fifth port can only be output through the sixth port; another path of polarization-maintaining light output by the second polarization-maintaining light splitter enters the fourth port of the second polarization-maintaining circulator and then passes through the fifth port through the corresponding channel of the multi-channel array to enter the second polarization-maintaining light receiving port of the silicon-based optoelectronic integrated chip; the polarization-maintaining light output from the second polarization-maintaining light receiving port of the silicon-based optoelectronic integrated chip enters the fifth port of the second polarization-maintaining circulator through the corresponding channel of the multi-channel array and is output from the sixth port to the corresponding channel of the multi-channel optical power meter.

[0021] In some embodiments, polarization-maintaining lights outputted from N-2 other polarization-maintaining light output ports of the silicon-based optoelectronic integrated chip are outputted from non-polarization-maintaining optical fibers to corresponding channels of the multi-channel optical power meter through corresponding channels of the multi-channel array.

[0022] In some embodiments, the testing device also includes an electrical parameter measurement link electrically connected by a control module, a multi-channel digital source meter and a probe card; wherein the control module is integrated with a computer control program and is configured to control the multi-channel digital source meter to output electrical signals or measure electrical signals through the computer control program; the probes on the probe card are crimped one-to-one onto the electrodes of the silicon-based optoelectronic integrated chip for transmission of electrical signals.

[0023] In some embodiments, the output wavelength of the tunable polarization-maintaining light source is continuously adjusted within the wavelength range of a preset band; the preset band is an O band or a C band; the tunable polarization-maintaining light source outputs polarization-maintaining light of a single wavelength or outputs polarization-maintaining light of a swept wavelength; the polarization-maintaining light is connected to a 1×2-way polarization-maintaining optical switch through a polarization-maintaining optical fiber, and the polarization state is kept unchanged.

[0024] In some embodiments, the operating wavelength range of the 1×2-way polarization-maintaining optical switch, the first polarization-maintaining optical splitter, the second polarization-maintaining optical splitter, at least two polarization-maintaining optical circulators and the multi-channel optical power meter at least includes the wavelength range of a preset band; the polarization state of the polarization-maintaining light passing through the 1×2-way polarization-maintaining optical switch, the first polarization-maintaining optical splitter, the second polarization-maintaining optical splitter, and at least two polarization-maintaining optical circulators remains unchanged.

[0025] According to another aspect of the present invention, a silicon-based optoelectronic integrated chip is provided. The optical parameters of the silicon-based optoelectronic integrated chip are measured after the silicon-based optoelectronic integrated chip is connected to the testing device of the silicon-based optoelectronic integrated chip described in the above aspect. The silicon-based optoelectronic integrated chip comprises:

[0026] An input port, one in number, configured to be aligned with a channel of the single-channel array and receive polarization-maintaining light from the first optical coupling link;

[0027] A light splitting monitoring module is configured to receive polarization-maintaining light passing through an input port, and to split the polarization-maintaining light into N light paths, and then monitor the input optical power of each light path through an input monitoring detector;

[0028] The optical modulation module is configured to receive N optical beams from the optical splitting monitoring module and output them after dimming;

[0029] An output monitoring module is configured to receive N light paths after dimming from the optical modulation module and monitor the output optical power of each light path through an output monitoring detector;

[0030] The output ports, which are N in number, are arranged to be aligned one by one with the N channels of the multi-channel array, and input polarization-maintaining light into the second optical coupling link through the multi-channel array and input non-polarization-maintaining light into the corresponding channel of the multi-channel optical power meter.

[0031] In some embodiments, the spectroscopic monitoring module of the silicon-based optoelectronic integrated chip includes: a cascaded first optical splitter, configured to split a beam of polarization-maintaining light received by the input port of the silicon-based optoelectronic integrated chip into N optical paths; N input monitoring detectors arranged on the N optical paths, configured to monitor the input optical power of each corresponding optical path.

[0032] In some embodiments, the optical modulation module of the silicon-based optoelectronic integrated chip includes: N second optical splitters, configured to split each of the N optical paths into two optical paths to obtain 2N optical paths; 2N silicon optical modulators arranged on the 2N optical paths, configured to dim each optical path; N phase shifters are correspondingly arranged on one of the two optical paths after dimming; N optical combiners are arranged after the N phase shifters, configured to combine every two optical paths to obtain N modulated optical paths.

[0033] According to another aspect of the present invention, a method for testing a silicon-based optoelectronic integrated chip is provided, wherein the optical parameters of the silicon-based optoelectronic integrated chip described in the above aspects are tested using the testing device described in the above aspects, and the testing method comprises the following steps:

[0034] Use the first optical coupling link to build an optical power ratio measurement link to obtain the optical power splitting ratio of the polarization-maintaining light output by the tunable polarization-maintaining light source at the output end and at the monitoring end;

[0035] Connect the electrical parameter measurement link, use a multi-channel digital source meter to provide operating voltage to the silicon-based optoelectronic integrated chip through the probe card and measure the current;

[0036] Using the first optical coupling link to calibrate the position of the single-channel array so that its channel is aligned with the input port of the silicon-based optoelectronic integrated chip;

[0037] Using a second optical coupling link to calibrate the position of the multi-channel array so that its N channels are respectively aligned with the N output ports of the corresponding silicon-based optoelectronic integrated chip;

[0038] Control the tunable light source to output polarization-maintaining light of a fixed wavelength, and use the optical parameter measurement link and the electrical parameter measurement link to test the minimum optical loss and phase shifter voltage operating point of the N channels of the silicon-based optoelectronic integrated chip;

[0039] The tunable light source is controlled to output polarization-maintaining light with swept wavelength, and the optical parameter measurement link and the electrical parameter measurement link are used to test the light response of the silicon-based optoelectronic integrated chip.

[0040] In some embodiments, the step of using the first optical coupling link to construct an optical power ratio measurement link specifically includes:

[0041] Connect one of the polarization-maintaining lights output by the first polarization-maintaining light splitter to channel 1 of the multi-channel optical power meter as a monitoring end optical path;

[0042] Connect another polarization-maintaining light output by the first polarization-maintaining light splitter to channel N+2 of the multi-channel optical power meter as an output end optical path;

[0043] When the tunable polarization-maintaining light source outputs swept wavelength polarization-maintaining light, the optical power ratio of the output end optical path and the monitoring end optical path is measured at each wavelength point within the swept wavelength range.

[0044] In some embodiments, the steps of connecting the electrical parameter measurement link and using a multi-channel digital source meter to provide an operating voltage to the silicon-based optoelectronic integrated chip through a probe card and measure the current specifically include:

[0045] Turn off the tunable polarization-maintaining light source through the control module;

[0046] The control module controls the multi-channel digital source meter to apply a working voltage signal to all input monitoring detectors and output monitoring detectors in the silicon-based optoelectronic integrated chip through the probe card;

[0047] Measure the dark current corresponding to all input monitoring detectors and output monitoring detectors.

[0048] In some embodiments, in the above-mentioned step of calibrating the position of the single-channel array using the first optical coupling link, the position of the single-channel array is adjusted according to the change of the photocurrent of any input monitoring detector of the spectroscopic monitoring module in the silicon-based optoelectronic integrated chip; when the photocurrent of any input monitoring detector is monitored to reach a maximum value, the single-channel array is aligned with the input port of the silicon-based optoelectronic integrated chip.

[0049] In some embodiments, in the above-mentioned step of calibrating the position of the multi-channel array using the second optical coupling link, the position of the multi-channel array is adjusted according to the change of the photocurrent of the output monitoring detector corresponding to the first polarization-maintaining light receiving port and the second polarization-maintaining light receiving port in the output monitoring module within the silicon-based optoelectronic integrated chip; when the photocurrent of the first polarization-maintaining light receiving port and the second polarization-maintaining light receiving port is monitored to reach a balanced maximum value, the multi-channel array is aligned with the output port of the silicon-based optoelectronic integrated chip.

[0050] In some embodiments, the steps of controlling the tunable light source to output polarization-maintaining light of a fixed wavelength and using an optical parameter measurement link and an electrical parameter measurement link to test the minimum optical loss and phase shifter voltage operating point of N channels of the silicon-based optoelectronic integrated chip specifically include:

[0051] Controlling the tunable light source to output polarization-maintaining light of a corresponding preset optical power at a preset wavelength point;

[0052] Control the multi-channel digital source meter to apply the working voltage to N phase shifters in the silicon-based optoelectronic integrated chip through the probe card and measure the working current corresponding to the N phase shifters to obtain the voltage and current characteristics of the phase shifters;

[0053] Collecting the variation curves of the photocurrents of N output monitoring detectors corresponding to the N phase shifters and the thermal powers of the N phase shifters;

[0054] Collect and record the optical powers corresponding to the N output ports of the silicon-based optoelectronic integrated chip under the thermal powers of the N phase shifters in the corresponding channels of the multi-channel optical power meter, and obtain the variation curve of the on-chip loss of the N output ports of the silicon-based optoelectronic integrated chip with the thermal powers of the N phase shifters;

[0055] The maximum optical power on the curve of on-chip loss of each output port of the silicon-based optoelectronic integrated chip varying with the thermal power of the corresponding phase shifter is the minimum loss of the output port at a preset wavelength point, and the phase shifter voltage corresponding to the minimum loss is the phase shifter voltage operating point.

[0056] In some embodiments, the steps of controlling the tunable light source to output polarization-maintaining light of swept wavelength and using an optical parameter measurement link and an electrical parameter measurement link to test the light responsivity of the silicon-based optoelectronic integrated chip specifically include:

[0057] The operating voltages of the N phase shifters in the silicon-based optoelectronic integrated chip are respectively set to the voltages applied to the corresponding N channels when the minimum loss on the chip is obtained at a preset wavelength point;

[0058] Controlling the tunable light source to output wavelength-swept polarization-maintaining light within a preset wavelength band;

[0059] Control the multi-channel digital source meter to measure the photocurrent of all input monitoring detectors and output monitoring detectors in the silicon-based optoelectronic integrated chip through the probe card;

[0060] Calculate the photoresponsivity curve of each input monitoring detector through the photocurrent and dark current corresponding to each input monitoring detector;

[0061] The photoresponsivity curve of each output monitoring detector is calculated by the photocurrent and dark current corresponding to each output monitoring detector.

[0062] The testing device for silicon-based optoelectronic integrated chip, silicon-based optoelectronic integrated chip and testing method thereof provided by the embodiments of the present invention have at least one or part of the following advantages:

[0063] (1) The test device and test method of the silicon-based optoelectronic integrated chip provided by the embodiments of the present invention realizes the simultaneous completion of the coupling alignment between the silicon-based optoelectronic integrated chip and the optical fiber array and the measurement of its optical performance parameters by multiplexing the optical coupling link and the optical parameter measurement link in the time domain, thereby greatly simplifying the optical path design of the test system;

[0064] (2) The testing device and testing method of the silicon-based optoelectronic integrated chip provided in the embodiment of the present invention switches and splits two optical coupling links through a 1×2-way polarization-maintaining optical switch and a polarization-maintaining optical splitter, and only one polarization-maintaining light source is used to achieve the coupling alignment of the optical fiber arrays at the input and output ends of the silicon-based optoelectronic integrated chip respectively;

[0065] (3) The testing device and testing method of the silicon-based optoelectronic integrated chip provided in the embodiment of the present invention switches and splits two coupled optical paths through a 1×2-way polarization-maintaining optical switch and a polarization-maintaining optical splitter to form different optical measurement optical paths. Only one polarization-maintaining light source is used in combination with wavelength adjustment to measure the optical performance parameters of various silicon-based optoelectronic integrated chips, thereby simplifying the design of the coupled test optical path, reducing the use of coupling or measurement devices, and reducing the test cost.

[0066] (4) The testing device and testing method of the silicon-based optoelectronic integrated chip provided in the embodiment of the present invention realizes the time domain multiplexing of the output light from the silicon-based optoelectronic integrated chip and the polarization-maintaining light from the testing device on the second optical coupling link through the multi-port unidirectional transmission characteristics of the polarization-maintaining optical circulator, which greatly simplifies the optical path design in the evaluation process of the silicon-based optoelectronic integrated chip;

[0067] (5) The silicon-based optoelectronic integrated chip provided by the embodiment of the present invention has input and output monitoring detectors arranged inside it, which helps the testing device of the present invention to directly obtain the internal optoelectronic parameters of the silicon-based optoelectronic integrated chip through the electrical measurement link, further simplifies the testing method and testing operation flow of the silicon-based optoelectronic integrated chip, and improves the testing efficiency of the silicon-based optoelectronic integrated chip;

[0068] (6) The testing method of the silicon-based optoelectronic integrated chip provided in the embodiment of the present invention uses a beam of tunable polarization-maintaining light to realize two optical coupling links in a set of optical links to respectively align the input and output ends of the silicon-based optoelectronic integrated chip with the optical fiber array and combines an optical measurement link to measure the optical performance parameters of the silicon-based optoelectronic integrated chip, thereby greatly improving the testing speed and efficiency of the silicon-based optoelectronic integrated chip and reducing the manufacturing cost of mass production of silicon-based optoelectronic integrated chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] These and / or other aspects and advantages of the present invention will become apparent and readily understood from the following description of the preferred embodiments in conjunction with the accompanying drawings, in which:

[0070] Figure 1 A schematic structural diagram of a testing device for a silicon-based optoelectronic integrated chip according to an embodiment of the present invention;

[0071] Figure 2 A schematic diagram of the internal structure of a silicon-based optoelectronic integrated chip according to another embodiment of the present invention;

[0072] Figure 3 for Figure 1 A schematic diagram of a single channel of a single channel array in a test device is shown;

[0073] Figure 4 for Figure 1 A schematic diagram of N channels of a multi-channel array in the test device shown;

[0074] Figure 5 for Figure 1 The structure and optical path diagram of the polarization-maintaining circulator in the test device shown;

[0075] Figure 6 A flowchart of a method for testing a silicon-based optoelectronic integrated chip according to another embodiment of the present invention;

[0076] Figure 7 For Figure 1 The test setup shown is being performed Figure 6 The optical path connection schematic diagram in step S100 is shown;

[0077] Figure 8 For use Figure 1 The test setup shown is for Figure 2 The photocurrent curve diagram of the output monitoring detector of the corresponding output port of the silicon-based optoelectronic integrated chip when the output port is positionally calibrated with the multi-channel array. DETAILED DESCRIPTION

[0078] The technical solution of the present invention is further specifically described below by examples and in conjunction with the accompanying drawings. In the specification, the same or similar reference numerals indicate the same or similar components. The following description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the overall inventive concept of the present invention and should not be construed as a limitation of the present invention.

[0079] It should also be understood that, although the terms "first", "second", etc. or sequence numbers "1, 2, ..., N-1, N", etc. may be used to describe components or device ports in the following embodiments of the present invention, these components or device ports should not be limited to these terms. These terms are only used to distinguish components or device ports from each other.

[0080] Silicon photonics is a new generation of technology that uses metal oxide semiconductor (CMOS) technology to develop and integrate optical devices on silicon and silicon-based substrate materials (such as silicon, silicon-on-insulator substrate SOI, etc.). Silicon photonics devices manufactured by silicon photonics technology include active devices (such as lasers, modulators, photodetectors, etc.) and passive devices (planar waveguides, gratings, edge couplers, etc.), forming basic units that can realize various functions. Based on these basic units, light emitting / light receiving integrated chips are constructed, and array applications are carried out, such as silicon-based photonic integrated circuits (Photonics Integrated Circuit), or PIC chips.

[0081] Take a single-channel optical transmitter PIC chip as an example. Generally, it integrates 1 input edge coupler and 1 output edge coupler, 2 3dB couplers, 2 monitoring detectors (MPD) (including 1 input InMPD and 1 output OutMPD), 2 silicon photonic modulators (MOD), and 1 phase shifter (Heater). When the performance parameters of the PIC chip need to be evaluated, multiple parameters need to be evaluated, including but not limited to the following evaluation items:

[0082] (1) Regarding the dark current of the monitoring detectors InMPD and OutMPD;

[0083] (2) Voltage and current IV characteristics of the phase shifter;

[0084] (3) Monitor the change curve of the photocurrent of the detector OutMPD with the thermal power of the phase shifter;

[0085] (4) Determine the in-phase voltage operating point (Inphase operating point) by the curve of the change of the port on-chip loss with the thermal power of the phase shifter;

[0086] (5) monitoring the photoresponsivity curves of the detector InMPD and OutMPD in a specific wavelength band;

[0087] (6) Minimum on-chip loss (Inphase Loss) corresponding to a specific band, etc.

[0088] Usually, the measurement of each of the above parameter items requires the construction of a corresponding measurement system and the use of a corresponding measurement method. For each additional channel of the PIC chip, the number of devices on it will double, and a splitter (BS) will be added at the optical input end. In this way, it is often necessary to build multiple measurement systems to complete the performance evaluation of a PIC chip, which is not only time-consuming and labor-intensive, but also has a low evaluation efficiency.

[0089] On the other hand, the prerequisite for the evaluation of PIC chips is to first complete the optical alignment of the fiber array (FA fiberarray) and the edge coupler (EC). Therefore, the optical coupling system for achieving optical alignment also needs to be built separately. For multi-channel light-emitting PIC chips, due to the long spatial distance between the EC at the input end and the EC at the output end, and limited by the processing tolerance of the fiber array, it will be very difficult to use a large-scale multi-channel fiber array to complete all optical path couplings. Usually, at least two fiber arrays are used to complete the input optical path coupling and the output optical path coupling respectively.

[0090] For the chip research and development stage, the above-mentioned discrete optical coupling measurement system and multi-parameter measurement system are applicable. However, when the chip enters the product production stage, the method of first building a coupling system to complete the optical coupling and then building a test system to evaluate parameters one by one is far from meeting the needs. An integrated coupling measurement system is urgently needed to efficiently and quickly complete the coupling of the PIC chip and the optical fiber array and the measurement of all its performance parameters at one time.

[0091] According to the edge coupler and fiber array coupling alignment schemes considered during the design of the PIC chip, there are two types: one is to deploy an optical loopback structure and complete the coupling by monitoring the changes in optical loopback loss; the other is to use the existing monitoring detector (MPD) on the PIC chip and complete the coupling by monitoring the changes in the photocurrent of the MPD.

[0092] Therefore, the embodiments of the present invention propose a new test device and test method for evaluating the performance parameters of PIC chips based on multi-channel light emission designed based on monitoring detector coupling. Only one set of optical path system is built, and time domain multiplexing is performed by converting optical paths with different functions to achieve the one-time completion of the optical path coupling of the optical fiber array and the evaluation of many performance parameter items.

[0093] See also Figure 1 , shows a test device 100 for a silicon-based optoelectronic integrated chip (hereinafter referred to as a PIC chip) according to an embodiment of the present invention. The test device 100 includes the following main components along the light output path:

[0094] A tunable polarization-maintaining light source 10 configured to output polarization-maintaining light;

[0095] A 1×2-way polarization-maintaining optical switch 20, a polarization-maintaining optical splitter 30 (including a first polarization-maintaining optical splitter 31 and a second polarization-maintaining optical splitter 32), a polarization-maintaining optical circulator 40, a single-channel array 60 and a multi-channel array 70 for completing the coupling alignment between the optical fiber array and the output port and input port of the PIC chip; and a multi-channel optical power meter 50 for completing the optical and electrical parameter measurement and an electronic control unit 80 composed of a control module 81, a multi-channel digital source meter 82 and a probe card 83 electrically connected.

[0096] like Figure 1 As shown, by connecting the above-mentioned main components through electrical wires and optical fibers, a first optical coupling link L1, a second optical coupling link L2, an optical parameter measurement link (including L3-1 and L3-2) and an electrical parameter measurement link (including L4-1, L4-2, L4-3, L4-4 and L4-5) can be formed.

[0097] The first optical coupling link L1 includes a first polarization-maintaining optical splitter 31 that allows polarization-maintaining light emitted by the tunable polarization-maintaining light source 10 to pass through, a single-channel array 60 and an input port Lo of the PIC chip 200 , ie, an optical path L1 - 1 .

[0098] The second optical coupling link L2 includes a second polarization-maintaining optical splitter 32 that allows the polarization-maintaining light to pass through, at least two polarization-maintaining optical circulators 40, a multi-channel array 70, and at least two polarization-maintaining light output ports Txn of the PIC chip 200, where n is an integer greater than or equal to 2; when two polarization-maintaining optical circulators 40 are used, two corresponding branches are formed, namely L2-1 and L2-2.

[0099] The 1×2-way polarization-maintaining optical switch 20 is configured to switch polarization-maintaining light from the tunable polarization-maintaining light source 10 between the first optical coupling link L1 and the second optical coupling link L2 .

[0100] The optical parameter measurement link is formed by time domain multiplexing of the first optical coupling link L1 and the second optical coupling link L2. In the optical parameter measurement link, the polarization-maintaining light is sequentially input to the input port Lo of the PIC chip 200 through the 1×2 polarization-maintaining optical switch 20, the first polarization-maintaining optical splitter 31 and the single-channel array 60, that is, the optical path L3-1, which is time domain multiplexed with the optical path L1-1; thereafter, the polarization-maintaining light is output from all the output ports Txn (where n is an integer greater than or equal to 2) of the PIC chip 200 through the corresponding channels of the multi-channel array 70 to the corresponding channels of the multi-channel optical power meter 50, that is, the optical path L3-2, where some channels of the multi-channel array 70 (for example Figure 1 Channel 1 and channel N) of the multi-channel array 70 are shown to be time-domain multiplexed with a portion of L2-1 and L2-2, respectively.

[0101] The electrical parameter measurement link includes control links L4-1, L4-2, L4-3 and L4-4, which respectively use the control module 81 to perform circuit control on the tunable polarization-maintaining light source 10, the 1×2-way polarization-maintaining optical switch 20, the multi-channel digital source meter 82 and the multi-channel optical power meter 50 through the control lines; at the same time, the control module 81 is integrated with a computer control program and is configured to control, for example, the output wavelength (including a certain wavelength and a swept wavelength) of the tunable polarization-maintaining light source 10, the optical path switching of the 1×2-way polarization-maintaining optical switch 20, the collection of optical power measurement data by the multi-channel optical power meter 50, the output of electrical signals or the measurement of electrical signals by the multi-channel digital source meter 82, and the collection, processing, drawing, and storage of measurement data through the computer control program.

[0102] The electrical parameter measurement link also includes an electrical signal transmission link L4-5, which connects the multi-channel digital source meter 82 and the probe card 83 through a circuit line, and the probes of the probe card 83 are crimped one-to-one on the electrodes of the PIC chip 200, for example, the probes are electrically connected to the input or output monitoring detector (MPD) in the PIC chip 200, or to the phase shifter (Heater), etc., to realize the electrical signal transmission between the PIC chip 200 and the multi-channel digital source meter 82.

[0103] In one example, alternatively, instead of integrating the above-mentioned first optical coupling link, the second optical coupling link and the optical parameter measurement link into the same optical path system, the optical coupling link and the optical parameter measurement link can also be separated. For example, first build the optical coupling link part to complete the alignment of the multi-channel optical fiber array and the output and input ports of the PIC chip; then build the measurement system of each parameter of the PIC chip in turn, and complete the measurement of each parameter respectively. The advantage of this solution is that only one or several specified parameters need to be measured, and all parameters do not need to be measured at one time, but in the actual chip production process, there are still disadvantages such as slow measurement speed, low efficiency, and high testing cost.

[0104] As mentioned above, there are generally two solutions for coupling and aligning the edge coupler EC and the optical fiber array FA used in the design process of the PIC chip: one is to deploy an optical loopback structure and complete the coupling alignment by monitoring the change of the optical loopback loss; the other is to use the monitoring detector (MPD) originally existing on the PIC chip to complete the coupling alignment by monitoring its photocurrent change. The test device 100 proposed in the embodiment of the present invention is based on monitoring the monitoring detector inside the PIC chip to achieve coupling alignment between the optical fiber array and the multiple ports of the input port and output port of the PIC chip. The specific coupling alignment process is described below.

[0105] In order to clearly explain how this embodiment realizes the alignment of the optical fiber array and the input and output ports of the PIC chip and the measurement of all optical parameters in the same optical path system by switching between different optical coupling links, the subsequent description is based on the PIC chip 200 provided by another embodiment of the present invention. Figure 2 , shows the internal structure of the PIC chip 200 of this embodiment, and a spectroscopic monitoring module 210, an optical modulation module 220 and an output monitoring module 230 are sequentially arranged along the optical path direction between the input port Lo and the output port Txn of the PIC chip 200.

[0106] The number of the input port Lo is set to one, and the input port Lo is configured to be aligned with a single channel of the single channel array 60 in the first optical coupling link L1 of the test device 100 .

[0107] The optical splitting monitoring module 210 is configured to receive polarization-maintaining light passing through the input port Lo, split the polarization-maintaining light into n optical paths, and then monitor the input optical power of each optical path through the input monitoring detector 212 (MPD).

[0108] In one example, the optical splitting monitoring module 210 specifically includes: a cascaded first optical splitter 211 (BS), configured to split a beam of polarization-maintaining light received by the input port Lo into n optical paths, which actually correspond to the final output port Txn. For example, when n=8, that is, there are 8 output ports, 7 first optical splitters 211 need to be cascaded to sequentially split one optical path into two optical paths through one BS, and then split the two optical paths into four optical paths through one BS respectively, and finally split the four optical paths into eight optical paths through one BS respectively; and n input monitoring detectors 212 (MPD) arranged on the n optical paths, configured to monitor the input optical power of each corresponding optical path.

[0109] The optical modulation module 220 is configured to receive n light beams from the optical splitting monitoring module 210 and output them after dimming.

[0110] In one example, the optical modulation module 220 specifically includes: n second optical splitters 221 (BS), configured to split each of the n optical paths from the optical splitting monitoring module 210 into two optical paths, to obtain 2n optical paths; 2n silicon optical modulators 222 (MOD) arranged on the 2n optical paths, configured to dim each optical path; n phase shifters 223 (Heater) are arranged on one of the two optical paths after dimming; n optical combiners 224 (BC) are arranged after the n phase shifters 223, configured to combine each two optical paths, to obtain n modulated optical paths. Figure 2As shown, after each light beam passes through each corresponding second optical splitter 221, each light beam is divided into two beams again, one of which is connected to the silicon light modulator 222 and the phase shifter 223 in sequence, and the other light is only connected to the silicon light modulator 222. Afterwards, the two light beams are combined and output through a corresponding optical combiner 224.

[0111] The output monitoring module 230 is configured to receive the n light paths after dimming from the optical modulation module 220 and monitor the output optical power of each light path through an output monitoring detector 231 (MPD).

[0112] The number of output ports Txn is set to N, that is, n=N, and the order is output ports Tx1, Tx2, Tx3, ..., Tx(N-2), Tx(N-1), TxN, where N is an integer greater than or equal to 2. At the same time, in the PIC chip 200, the optical splitting monitoring module 210 divides the polarization-maintaining light received by the input port Lo into N beams, and then in the optical modulation module 220, the N beams are first divided into 2N beams by the second optical splitter 221, and then every two beams of the 2N beams are combined by the optical combiner 224 to finally form N beams of light as output light to enter the corresponding output port Txn. The N output ports Txn are configured to be aligned one by one with the N channels of the multi-channel array 70 in the second optical coupling link L2 of the test device 100.

[0113] The PIC chip 200 is used as the chip to be tested 200. The test device 100 of this embodiment is used to first calibrate the alignment between the optical fiber array and the input and output ports of the chip to be tested 200, and then the optical performance parameters of the chip to be tested 200 are measured. Figure 1 As shown, the specific configuration of the testing device 100 is as follows.

[0114] In one example, according to the chip under test 200 having N output ports Txn, the number of channels of the multi-channel array 70 is N, and the sequence numbers are channel 1, channel 2, channel 3, ..., channel N-2, channel N-1, channel N, and the N channels correspond one to one with the N output ports Txn of the chip under test 200. For example, the output port Tx1 corresponds to channel 1, Tx2 corresponds to channel 2... or Tx1 corresponds to channel N, Tx2 corresponds to channel N-1... and so on. The sequence numbering and the correspondence between the sequence numbers are only used to distinguish different channels or ports and their corresponding positions. The arrangement rules of the sequence numbers and the correspondence rules between the sequence numbers can be freely set according to the usage habits, and those skilled in the art should not be understood as a limitation of the present invention. In order to facilitate the clear description of the technical solution, this embodiment selects the corresponding rule that the output port Tx1 of the chip under test 200 corresponds to channel 1 of the multi-channel array 70, Tx2 corresponds to channel 2... and so on.

[0115] In one example, theoretically, the number of output ports of the first polarization-maintaining optical splitter 31 and the second polarization-maintaining optical splitter 32 is at least two, and the number of optical paths to be split can be set to have two, three or more output ports according to the required number of optical paths.

[0116] In one example, combining Figure 1 and Figure 3 As shown, for the first polarization-maintaining optical splitter 31, it is set on the first optical coupling link L1, and is used to calibrate the alignment position of a single channel of the single-channel array 60 and an input port Lo of the chip to be tested 200. Then, the first polarization-maintaining optical splitter 31 only needs two output ports to split the input polarization-maintaining light into two paths (L1-1 and L1-2). When the single channel is aligned with the input port Lo, the polarization-maintaining light on the optical path L1-1 enters the input port Lo of the chip to be tested 200 through the single-channel array 60, and the polarization-maintaining light on the optical path L1-2 enters the corresponding channel of the multi-channel optical power meter 50.

[0117] In one example, combining Figure 1 and Figure 4 As shown, for the second polarization-maintaining optical splitter 32, it is set on the second optical coupling link L2, and is used to calibrate the alignment position of the N channels of the multi-channel array 70 and the N output ports Txn of the chip under test 200. It can be foreseen that if the two outermost output ports (Tx1 and TxN) of the N output ports Txn and the two outermost channels (channel 1 and channel N) of the N channels of the multi-channel array 70 are calibrated through optical path coupling, then it can be determined that the N output ports Txn and the N channels have completed the one-to-one alignment of the positions. Accordingly, the second polarization-maintaining optical splitter 32 also only needs two output ports to split the input polarization-maintaining light into two paths (L2-1 and L2-2), which are respectively used to align the channel 1 of the multi-channel array 70 with the output port Tx1 of the chip under test 200 and the alignment of the channel N with the output port TxN.

[0118] In one example, corresponding to the above-mentioned alignment of only the two outermost channels of the multi-channel array 70 with the two outermost output ports of the chip to be tested 200, the output ports Tx1 and TxN of the chip to be tested 200 are set to receive polarization-maintaining light from the second optical coupling link, that is, the corresponding output port Tx1 is set to the first polarization-maintaining light receiving port, and the corresponding output port TxN is the second polarization-maintaining light receiving port. The output ports of the remaining N-2 chips to be tested 200 are not limited or additionally set. For silicon-based optoelectronic integrated chips, their output ports output polarization-maintaining light. After N beams of polarization-maintaining light are output, whether their polarization state remains unchanged will no longer be limited, that is, transmission can be achieved through polarization-maintaining optical fiber or non-polarization-maintaining optical fiber. Specifically in this example, since the output ports Tx1 and TxN need to receive polarization-maintaining light from the second optical coupling link for alignment with the optical fiber array, the polarization state must be kept unchanged. Correspondingly, the remaining N-2 output ports Tx2 to TxN-1 located in the middle maintain the setting of outputting other polarization-maintaining lights when there is light input, corresponding to N-2 other polarization-maintaining light output ports, and the polarization state of the other polarization-maintaining lights outputted therefrom will no longer be limited.

[0119] In one example, if Figure 1 As shown, a multi-channel optical power meter 50 is used to collect different optical power data of each channel under different monitoring conditions as basic data for performance evaluation of the chip under test 200. Therefore, corresponding to the settings of the above-mentioned components and their ports, the multi-channel optical power meter 50 is set with N+2 channels.

[0120] In one example, among the N+2 channels of the above-mentioned multi-channel optical power meter 50, channel 1' is configured to receive one of the polarization-maintaining lights L1-2 output by the first polarization-maintaining light splitter 31; the N channels from channel 2' to channel N+1 are configured to receive the output lights of the N output ports Txn of the chip under test 200 correspondingly; and channel N+2 is configured to receive the other polarization-maintaining light L1-1 output by the first polarization-maintaining light splitter 31 during the optical parameter measurement process.

[0121] In one example, the polarization-maintaining light output by the N-2 other polarization-maintaining light output ports (output ports Tx2 to TxN-1) of the chip under test 200 is output by the non-polarization-maintaining optical fiber through the corresponding channels (channel 2 to channel N-1) of the multi-channel array 70 to the corresponding channels (channel 3' to channel N) of the multi-channel optical power meter 50.

[0122] In one example, corresponding to the two output ports and two polarization-maintaining optical paths provided by the second polarization-maintaining optical splitter 32, a polarization-maintaining optical circulator 40 is connected to each polarization-maintaining optical path. Figure 1 As shown, a first polarization-maintaining optical circulator 41 is connected to the optical path L2 - 1 , and a second polarization-maintaining optical circulator 42 is connected to the optical path L2 - 2 .

[0123] In one example, according to the characteristic that the polarization-maintaining circulator 40 has a single-channel transmission of the input light, see Figure 5 Alternatively, the polarization-maintaining circulator 40 of this embodiment has three ports for transmitting polarization-maintaining light. Taking the first polarization-maintaining circulator 41 as an example, it includes a first port A1, a second port B1 and a third port C1 that are separately arranged along the annular structure. Among them, when polarization-maintaining light enters the first port A1, the beam of polarization-maintaining light can only be output by the second port B1, and will not pass through the third port C1; when polarization-maintaining light enters the second port B1, the beam of polarization-maintaining light can only be output by the third port C1, and will not pass through the first port A1. Similarly, the second polarization-maintaining circulator 42 is set, that is, the fourth port A2, the fifth port B2 and the sixth port C2 are separately arranged along the annular structure.

[0124] In one example, after adding a polarization-maintaining optical circulator 40 to the second optical coupling link L2, time domain multiplexing of the optical path can be formed by connecting and transmitting through polarization-maintaining optical fibers. Figure 1 and Figure 5 , the specific light path is described as follows:

[0125] When aligning the optical fiber array, one of the polarization-maintaining lights L2-1 outputted from the second polarization-maintaining light splitter 32 enters the first port A1 of the first polarization-maintaining light circulator 41, passes through the second port B1 and the channel 1 of the multi-channel array 70 to enter the first polarization-maintaining light receiving port (output port Tx1) of the chip under test 200;

[0126] When the optical performance parameter test is performed after the alignment of the optical fiber array is completed, the polarization-maintaining light outputted from the first polarization-maintaining light receiving port (output port Tx1) of the chip to be tested 200 enters the second port B1 of the first polarization-maintaining circulator 41 through the channel 1 of the multi-channel array 70 and is outputted from the third port C1 to the corresponding channel (channel 2') of the multi-channel optical power meter 50;

[0127] During the above optical path coupling and optical testing process, time domain multiplexing is implemented in the optical path between the second port B1 of the first polarization-maintaining circulator 41 and the channel 1 of the multi-channel array 70 .

[0128] Similarly, when the optical fiber array is aligned, the polarization-maintaining light L2-2 outputted by the second polarization-maintaining light splitter 32 enters the fourth port A2 of the second polarization-maintaining light circulator 42, passes through the fifth port B2 and the channel N of the multi-channel array 70 to enter the second polarization-maintaining light receiving port (output port TxN) of the chip under test 200;

[0129] When the optical performance parameter test is performed after the optical fiber array alignment is completed, the polarization-maintaining light outputted from the second polarization-maintaining light receiving port (output port TxN) of the chip to be tested 200 enters the fifth port B2 of the second polarization-maintaining circulator 42 through the channel N of the multi-channel array 70 and is outputted from the sixth port C2 to the corresponding channel (channel N+1) of the multi-channel optical power meter 50;

[0130] During the above optical path coupling and optical testing process, time domain multiplexing is implemented in the optical path from the fifth port B2 of the second polarization-maintaining circulator 42 to the channel N of the multi-channel array 70 .

[0131] In one example, in order to facilitate the efficient determination of the full performance parameters of the chip 200 to be tested by the test device 100, the working band range of the test device 100 needs to be designed in advance. For the tunable polarization-maintaining light source 10 as the test light source, its output wavelength can be continuously adjusted within the wavelength range of the preset band; the specific preset band can be determined according to the actual working performance requirements of the chip 200 to be tested, such as the O band (wavelength range: 1260nm~1340nm), C band (wavelength range: 1527nm~1567nm) and the like that are generally adapted to multi-channel PIC chips today; it can also be other communication wavelength ranges required by test conditions such as the E band, S band, L band, and U band. The enumeration of the preset bands here is only an illustrative example, and those skilled in the art should not be understood as a limitation of the present invention.

[0132] In one example, according to different performance evaluation requirements, the tunable polarization-maintaining light source 10 can output polarization-maintaining light of a single wavelength at a certain point in a specified preset band, or can output polarization-maintaining light of swept wavelength in the specified preset band.

[0133] In one example, the polarization-maintaining light output by the tunable polarization-maintaining light source 10 is transmitted in the first optical coupling link L1 and the second optical coupling link L2 through the polarization-maintaining optical fiber, and the polarization state is always kept unchanged during the transmission process. In other words, the polarization state of the polarization-maintaining light passing through the 1×2-way polarization-maintaining optical switch 20, the first polarization-maintaining optical splitter 31, the second polarization-maintaining optical splitter 32, the first polarization-maintaining optical circulator 41 and the second polarization-maintaining optical circulator 42 always remains unchanged.

[0134] In one example, correspondingly, non-polarization-maintaining light in the optical path, such as polarization-maintaining light from other N-2 output ports of the chip under test 200, no longer maintains the polarization state after leaving the chip under test 200 and can be transmitted using non-polarization-maintaining optical fiber.

[0135] In one example, after determining the preset band (i.e., the operating band) of the tunable polarization-maintaining light source 10, the operating wavelength range of the 1×2-way polarization-maintaining optical switch 20, the first polarization-maintaining optical splitter 31, the second polarization-maintaining optical splitter 32, the first polarization-maintaining optical circulator 41, the second polarization-maintaining optical circulator 42 and the multi-channel optical power meter 50 should at least include the wavelength range of the preset band.

[0136] Another embodiment of the present invention further provides a testing method for evaluating the optical parameters of the PIC chip 200 based on the above-mentioned testing device 100. Figure 6 , the test method mainly includes the following steps:

[0137] Step S100: using the first optical coupling link L1 to construct an optical power ratio measurement link, and obtaining an optical power splitting ratio of the polarization-maintaining light output by the tunable polarization-maintaining light source 10 at the output end and at the monitoring end.

[0138] Specifically, see Figure 7 , shows the optical path connection and layout of the measuring device 100 when performing step S100, and the steps of using the first optical coupling link L1 to construct an optical power ratio measurement link include:

[0139] S11, connect one of the polarization-maintaining light L1-2 outputted from the first polarization-maintaining light splitter 31 to the channel 1' of the multi-channel optical power meter 50 as a monitoring end optical path M;

[0140] S12, connect the other polarization-maintaining light L1-1 output by the first polarization-maintaining optical splitter 31 to the channel N+2 of the multi-channel optical power meter 50 as the output optical path X, that is, at this time, the branch optical path L1-1 of the first optical coupling link L1 changes from being connected to the single-channel array 60 to being connected to the multi-channel optical power meter 50 to form a power measurement branch L3-1;

[0141] S13, when the tunable polarization-maintaining light source 10 outputs swept wavelength polarization-maintaining light, measuring the optical power ratio of the output end optical path X and the monitoring end optical path M at each wavelength point within the swept wavelength range.

[0142] In one example, the computer control program in the control module 81 controls the 1×2-way polarization-maintaining optical switch 20 to switch the output optical path to the first optical coupling link adjusted by step S11 and step S12, i.e., the optical power ratio measurement link. The computer control program continues to control the tunable polarization-maintaining light source 10 to scan the wavelength within the measurement wavelength range to output the optical power (in dBm as the optical power value unit). At this time, the multi-channel optical power meter 50 measures the access optical power values ​​p1 of its channel 1 and channel N+2 at each wavelength point i. i and P(N+2) i , we can get the optical power splitting ratio θ between the output optical path X and the monitoring terminal optical path M within the measurement wavelength range.i =P(N+2) i -P1 i Thus, in the measurement process of any parameter, when the tunable polarization-maintaining light source 10 outputs optical power, as long as the value of the received optical power of the monitoring terminal optical path M is paid attention to or recorded, the optical power splitting ratio θ can be used to obtain the optical power splitting ratio θ. i The formula is used to calculate the value of the optical power output from the corresponding output optical path X to the chip under test 200.

[0143] Step S200: connecting an electrical parameter measurement link, using a multi-channel digital source meter 82 to provide a working voltage to the chip under test 200 through a probe card 81 and measure the current.

[0144] Specifically, first, the tunable polarization-maintaining light source 10 is turned off through the control module 81 to suspend the optical path transmission; then, the control module 81 controls the multi-channel digital source meter 82 to apply the working voltage signal to all the input monitoring detectors 212 (located in the spectroscopic monitoring module 210) and the output monitoring detectors 231 (located in the output monitoring module 230) in the chip to be tested 200 through the probe card 83; and measures the dark current corresponding to all the input monitoring detectors 212 and the output monitoring detectors 231.

[0145] Step S300 : using the first optical coupling link L1 to calibrate the position of the single channel array 60 so that its single channel is aligned with the input port Lo of the chip under test 200 .

[0146] Specifically, the position of the single-channel array is adjusted according to the change of the photocurrent of any input monitoring detector 212 (MPD) in the spectroscopic monitoring module 210 within the chip under test 200; when the photocurrent of any input monitoring detector 212 is monitored to reach a maximum value, it indicates that a single channel in the single-channel array 60 is aligned with the input port Lo of the chip under test 200.

[0147] In one example, the control module 81 controls the tunable polarization-maintaining light source 10 to output a specified optical power Pa at a fixed wavelength (e.g., 1310 nm) through a computer control program; thereafter, the computer control program continues to control the 1×2-way polarization-maintaining optical switch 20 to switch the output optical path to the first optical coupling link L1, monitors the photocurrent change of any input monitoring detector 212 (MPD) in the optical splitting monitoring module 210 on the input end side of the chip under test 200, and adjusts the position of the single-channel array 60 accordingly. When any of the above-mentioned input monitoring detectors 212 (MPD) monitors the maximum photocurrent, the single channel of the single-channel array 60 is aligned with the input port Lo of the chip under test 200 to the optimal position.

[0148] Step S400 : using the second optical coupling link L2 to calibrate the position of the multi-channel array 70 so that its N channels are respectively aligned with the corresponding N output ports Txn of the chip 200 under test.

[0149] Specifically, the calibration principle is the same as that of step S300, and the position of the multi-channel array 70 is adjusted according to the change of the photocurrent of the output monitoring detector 231 (MPD) corresponding to the first polarization-maintaining light receiving port (output port Tx1) and the second polarization-maintaining light receiving port (output port TxN) in the output monitoring module 230 of the chip under test 200.

[0150] Furthermore, since the number of channels and output ports to be calibrated is greater than 1, it is necessary to perform a balanced adjustment on the position of the multi-channel array 70. Figure 8 , showing that when the photocurrents of the first polarization-maintaining light receiving port (output port Tx1) and the second polarization-maintaining light receiving port (output port TxN) reach a balanced maximum value, the multi-channel array 70 is aligned one by one with the output ports Txn of the chip under test 200.

[0151] In one example, the control module 81 controls the tunable polarization-maintaining light source 10 to output a specified optical power Pa at a fixed wavelength (such as 1310 nm) through a computer control program; thereafter, the computer control program continues to control the 1×2-way polarization-maintaining optical switch 20 to switch the output optical path to the second optical coupling link L2, monitors the photocurrent changes of the output monitoring detectors 231 (MPD) corresponding to the output ports Tx1 and TxN in the output monitoring module 230 of the chip under test 200, and adjusts the position of the multi-channel array 70 accordingly. When the two output monitoring detectors 231 detect that the photocurrent balance is the maximum, the N channels of the multi-channel array 70 are aligned with the N output ports Txn of the chip under test 200 to the optimal position. Figure 8 As shown, the dotted line is the monitoring photocurrent change curve of the position of the multi-channel array 70 and the output monitoring detector 231 at the output port Tx1, and the solid line is the monitoring photocurrent change curve of the position of the multi-channel array 70 and the output monitoring detector 231 at the output port TxN. The position Q of the multi-channel array 70 corresponding to the point P is the optimal position for aligning the N channels of the multi-channel array 70 with the N output ports Txn of the chip 200 to be tested.

[0152] Step S500: Control the tunable light source 10 to output polarization-maintaining light of a fixed wavelength, and use the optical parameter measurement link and the electrical parameter measurement link to test the minimum optical loss of the N channels of the chip 200 to be tested and the voltage operating point of the phase shifter 223. Specifically, the following steps are included:

[0153] S51, controlling the tunable light source 10 to output polarization-maintaining light of a preset optical power corresponding to a preset wavelength point;

[0154] S52, controlling the multi-channel digital source meter 82 to apply a working voltage to the N phase shifters 223 (heaters) in the chip under test 200 through the probe card 83 and measuring the working currents corresponding to the N phase shifters 223 to obtain the voltage-current IV characteristics of the phase shifters 223;

[0155] S53, collecting the variation curves of the photocurrents of the N output monitoring detectors 231 (MPD) corresponding to the N phase shifters 223 (Heater) and the heat powers of the N phase shifters 223;

[0156] S54, collecting and recording the optical powers corresponding to the N output ports Txn of the chip under test 200 in the corresponding channels of the multi-channel optical power meter 50 under the heat powers of the N phase shifters 223 (heaters), and obtaining a variation curve of the on-chip loss of the N output ports Txn of the chip under test 200 with the heat powers of the N phase shifters 223;

[0157] The maximum optical power on the curve of the on-chip loss of each output port Txn of the chip under test 200 varying with the thermal power of the corresponding phase shifter 223 is the minimum loss (InphaseLoss) of the output port at the preset wavelength point, and the voltage of the phase shifter 223 corresponding to the minimum loss is the voltage operating point of the phase shifter 223.

[0158] In one example, the control module 81 controls the tunable polarization-maintaining light source 10 to output a specified optical power Pa at a fixed wavelength (e.g., 1310 nm) through a computer control program, and continues to control the 1×2-way polarization-maintaining optical switch 20 to switch the output optical path to the first optical coupling link L1 to control the multi-channel digital source meter 82 to apply a working voltage VN to the phase shifters 223 (heaters) of the N channels on the output side of the chip under test 200 through the probe card 83. j (j=1, 2...D, D is the number of voltage points), measure the working current IN of the phase shifter 223 j , the voltage-current IV characteristic of the phase shifter 223 is obtained. At the same time, at each operating voltage point VN of the phase shifter 223 j The photocurrent IPN of the output monitoring detector 231 (MPD) connected to the corresponding output optical path is collected. j (IP represents photocurrent, N represents channel number, and j represents working voltage point). In this way, the photocurrent IPN of the output monitoring detector 231 is measured. j The corresponding thermal power of the phase shifter 223 (thermal power: HN j =VN j *IN jAt the same time, in the multi-channel optical power meter 50 of the channel 2 'to channel N + 1 record each thermal power point HN j The output optical power PN of the N output ports Txn of the chip under test 200 under the condition j , thus measuring the on-chip losses (P a -PN j ) with the phase shifter 223 thermal power HN j The output optical power PN is found on the curve. j Maximum point PN max , which is the in-phase operating point (Inphase operating point) of the N channels of the chip under test 200. At this time, the optical path loss is the smallest, and the output power PN is recorded. max The corresponding voltage VN max , which is the voltage operating point of the phase shifter 223. The above measurement process is performed simultaneously on N channels.

[0159] Step S600: Control the tunable light source 10 to output polarization-maintaining light with a swept wavelength, and use the optical parameter measurement link and the electrical parameter measurement link to test the optical responsivity of the chip 200 to be tested. Specifically, the following steps are included:

[0160] S61, setting the operating voltages of the N phase shifters 223 in the chip under test 200 to the voltages applied to the corresponding N channels when the minimum on-chip loss is obtained at the preset wavelength point in step S500;

[0161] S62, controlling the tunable light source 10 to output wavelength-swept polarization-maintaining light within a preset wavelength range;

[0162] S63, controlling the multi-channel digital source meter 82 to measure the photocurrents of all the input monitoring detectors 212 (MPD) and the output monitoring detectors 231 (MPD) in the chip under test 200 through the probe card 83;

[0163] S64, calculating the photoresponsivity curve of each input monitoring detector 212 by using the photocurrent and dark current corresponding to each input monitoring detector 212 (MPD);

[0164] S65 , calculating the photoresponsivity curve of each output monitoring detector 231 through the photocurrent and dark current corresponding to each output monitoring detector 231 (MPD).

[0165] In one example, the control module 81 controls the multi-channel digital source meter 82 through the computer control program to apply the maximum working voltage VN to the phase shifter 223 (heater) on the N channels of the output side of the chip under test 200 through the probe card 83. maxThe computer control program continues to control the tunable polarization-maintaining light source 10 to start and scan the wavelength output optical power within the measurement wavelength range; at the same time, the multi-channel optical power meter 50 measures the access optical power value P1 of channel 1' at each wavelength point i i , the optical power splitting ratio θ obtained by step S100 i The calculation formula can be used to calculate the output optical power P of the output terminal optical path X i =P1 i +θ i At this time, the computer control program continues to control the multi-channel digital source meter 82 to collect the photocurrent IPN of all input monitoring detectors 212 and all output monitoring detectors 231 on the chip under test 200 at each wavelength point i through the probe card 83. ii and IPN oi (Where IP represents photocurrent, N represents the number of channels, i and o represent input and output respectively, and the last i represents the optical wavelength variable), according to the photoresponsivity calculation formula R i =(Photocurrent IP i -Dark current Id) / P i , where i represents the optical wavelength variable, the optical responsivity curves of all input monitoring detectors 212 and all output monitoring detectors 231 in the measurement band can be calculated:

[0166] In the spectroscopic monitoring module 210 on the input side of the chip under test 200, the light responsivity R of the input monitoring detector 212 corresponding to a certain k channel (k=1, 2, 3, . . . , N) under the condition of light wavelength i ii =(IPk ii -Idk i ) / (P1 i +θ i );

[0167] In the output monitoring module 230 at the output side of the chip under test 200, the light response R of the output monitoring detector 231 corresponding to the k channel under the light wavelength i is io =(IPk oi -Idk o ) / (P1 i +θ i ).

[0168] In one example, if it is necessary to further obtain the channel loss of the chip under test 200, the computer control program of the control module 81 can continue to control the multi-channel optical power meter 50 to collect the measured optical power Pk from channel 2' to channel N+1 at each wavelength point i. i (When k = 1, Pk i The optical power collected for channel 2', when k = 2, Pk iWhen k = N, Pk is the optical power collected for channel 3'. i The optical power of channel N+1 is collected); the loss of channel k in the chip under test 200 is obtained as:

[0169] The loss of N-2 other polarization-maintaining light channels (i.e., channel 2 to channel N-1) is ILk=P1 i +θ i -Pk i ,(k=2、3……、N-1);

[0170] The loss of two polarization-maintaining optical channels (i.e., channel 1 and channel N) is ILk = P1 i +θ i -Pk i -ILc, (k = 1 and N);

[0171] Among them, ILc is the insertion loss of the port of the polarization-maintaining circulator 40 when transmitting the polarization-maintaining light at the output end of the chip under test 200 to the corresponding channel of the multi-channel optical power meter 50; that is, when k=1, it corresponds to the first polarization-maintaining light receiving port (output port Tx1), and at this time, ILc is the insertion loss from the second port B1 to the third port C1 of the first polarization-maintaining circulator 41; when k=N, it corresponds to the second polarization-maintaining light receiving port (output port TxN), and at this time, ILc is the insertion loss from the fifth port B2 to the sixth port C2 of the second polarization-maintaining circulator 42.

[0172] The testing device for silicon-based optoelectronic integrated chip, silicon-based optoelectronic integrated chip and testing method thereof provided by the embodiments of the present invention have at least one or part of the following advantages:

[0173] (1) The test device and test method of the silicon-based optoelectronic integrated chip provided by the embodiments of the present invention realizes the simultaneous completion of the coupling alignment between the silicon-based optoelectronic integrated chip and the optical fiber array and the measurement of its optical performance parameters by multiplexing the optical coupling link and the optical parameter measurement link in the time domain, thereby greatly simplifying the optical path design of the test system;

[0174] (2) The testing device and testing method of the silicon-based optoelectronic integrated chip provided in the embodiment of the present invention switches and splits two optical coupling links through a 1×2-way polarization-maintaining optical switch and a polarization-maintaining optical splitter, and only one polarization-maintaining light source is used to achieve the coupling alignment of the optical fiber arrays at the input and output ends of the silicon-based optoelectronic integrated chip respectively;

[0175] (3) The testing device and testing method of the silicon-based optoelectronic integrated chip provided in the embodiment of the present invention switches and splits two coupled optical paths through a 1×2-way polarization-maintaining optical switch and a polarization-maintaining optical splitter to form different optical measurement optical paths. Only one polarization-maintaining light source is used in combination with wavelength adjustment to measure the optical performance parameters of various silicon-based optoelectronic integrated chips, thereby simplifying the design of the coupled test optical path, reducing the use of coupling or measurement devices, and reducing the test cost.

[0176] (4) The testing device and testing method of the silicon-based optoelectronic integrated chip provided in the embodiment of the present invention realizes the time domain multiplexing of the output light from the silicon-based optoelectronic integrated chip and the polarization-maintaining light from the testing device on the second optical coupling link through the multi-port unidirectional transmission characteristics of the polarization-maintaining optical circulator, which greatly simplifies the optical path design in the evaluation process of the silicon-based optoelectronic integrated chip;

[0177] (5) The silicon-based optoelectronic integrated chip provided by the embodiment of the present invention has input and output monitoring detectors arranged inside it, which helps the testing device of the present invention to directly obtain the internal optoelectronic parameters of the silicon-based optoelectronic integrated chip through the electrical measurement link, further simplifies the testing method and testing operation flow of the silicon-based optoelectronic integrated chip, and improves the testing efficiency of the silicon-based optoelectronic integrated chip;

[0178] (6) The testing method of the silicon-based optoelectronic integrated chip provided in the embodiment of the present invention uses a beam of tunable polarization-maintaining light to realize two optical coupling links in a set of optical links to respectively align the input and output ends of the silicon-based optoelectronic integrated chip with the optical fiber array and combines an optical measurement link to measure the optical performance parameters of the silicon-based optoelectronic integrated chip, thereby greatly improving the testing speed and efficiency of the silicon-based optoelectronic integrated chip and reducing the manufacturing cost of mass production of silicon-based optoelectronic integrated chips.

[0179] Although some embodiments of the present general inventive concept have been shown and described, it will be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the present general inventive concept, the scope of which is defined by the claims and their equivalents.

Claims

1. A testing device for silicon-based optoelectronic integrated chips, It is characterized in that The testing device comprises: A tunable polarization-maintaining light source, configured to output polarization-maintaining light; A first optical coupling link includes a first polarization-maintaining optical splitter that allows the polarization-maintaining light to pass through, a single-channel array, and an input port of a silicon-based optoelectronic integrated chip; A second optical coupling link comprises a second polarization-maintaining optical splitter allowing the polarization-maintaining light to pass through, at least two polarization-maintaining optical circulators, a multi-channel array, and at least two polarization-maintaining light output ports of the silicon-based optoelectronic integrated chip; A 1×2-way polarization-maintaining optical switch is configured to switch the polarization-maintaining light between the first optical coupling link and the second optical coupling link.

2. The testing device according to claim 1, It is characterized in that The test device also includes an optical parameter measurement link formed by time domain multiplexing of the first optical coupling link and the second optical coupling link; In the optical parameter measurement link, the polarization-maintaining light is sequentially input to the input port of the silicon-based optoelectronic integrated chip through the 1×2 polarization-maintaining optical switch, the first polarization-maintaining optical splitter and the single-channel array; thereafter, the polarization-maintaining light is output from all output ports of the silicon-based optoelectronic integrated chip to the corresponding channels of the multi-channel optical power meter.

3. The testing device according to claim 2, It is characterized in that The number of output ports of each of the first polarization-maintaining optical splitter and the second polarization-maintaining optical splitter is at least two; When the number of output ports of the first polarization-maintaining optical splitter and the second polarization-maintaining optical splitter is two, and the number of all output ports of the silicon-based optoelectronic integrated chip is N, The at least two polarization-maintaining circulators are two in number and include a first polarization-maintaining circulator and a second polarization-maintaining circulator; The number of channels of the multi-channel array is N, and corresponds one-to-one to the N output ports of the silicon-based optoelectronic integrated chip, where N is an integer; The two outermost output ports of the N output ports of the silicon-based optoelectronic integrated chip are respectively set as a first polarization-maintaining light receiving port and a second polarization-maintaining light receiving port, and the remaining N-2 output ports are other polarization-maintaining light output ports; The number of channels of the multi-channel optical power meter is N+2.

4. The testing device according to claim 3, It is characterized in that In the N+2 channels of the multi-channel optical power meter, Channel 1 is configured to receive one of the polarization-maintaining lights output by the first polarization-maintaining light splitter; The N channels from channel 2 to channel N+1 are configured to correspondingly receive output light of the N output ports of the silicon-based optoelectronic integrated chip; Channel N+2 is configured to receive another path of polarization-maintaining light output by the first polarization-maintaining light splitter.

5. The testing device according to claim 4, It is characterized in that The first polarization-maintaining circulator comprises a first port, a second port and a third port; wherein, Light input through the first port can only be output through the second port; Light input through the second port can only be output through the third port; One of the polarization-maintaining lights output by the second polarization-maintaining light splitter enters the first port and then passes through the second port and the corresponding channel of the multi-channel array to enter the first polarization-maintaining light receiving port of the silicon-based optoelectronic integrated chip; The polarization-maintaining light outputted from the first polarization-maintaining light receiving port of the silicon-based optoelectronic integrated chip enters the second port through the corresponding channel of the multi-channel array and is outputted from the third port to the corresponding channel of the multi-channel optical power meter.

6. The testing device according to claim 5, It is characterized in that The second polarization-maintaining circulator comprises a fourth port, a fifth port and a sixth port; wherein, Light input through the fourth port can only be output through the fifth port; Light input through the fifth port can only be output through the sixth port; The polarization-maintaining light of another path output by the second polarization-maintaining light splitter enters the fourth port and then passes through the fifth port and the corresponding channel of the multi-channel array to enter the second polarization-maintaining light receiving port of the silicon-based optoelectronic integrated chip; The polarization-maintaining light outputted from the second polarization-maintaining light receiving port of the silicon-based optoelectronic integrated chip enters the fifth port through the corresponding channel of the multi-channel array and is outputted from the sixth port to the corresponding channel of the multi-channel optical power meter.

7. The testing device according to claim 6, It is characterized in that The polarization-maintaining light outputted from the N-2 other polarization-maintaining light output ports of the silicon-based optoelectronic integrated chip passes through the corresponding channels of the multi-channel array and is outputted from the non-polarization-maintaining optical fiber to the corresponding channels of the multi-channel optical power meter.

8. The testing device according to any one of claims 1 to 7, It is characterized in that The test device also includes an electrical parameter measurement link electrically connected by a control module, a multi-channel digital source meter and a probe card; wherein, The control module is integrated with a computer control program and is configured to control the multi-channel digital source meter to output an electrical signal or measure an electrical signal through the computer control program; The probes on the probe card are pressed one-to-one on the electrodes of the silicon-based optoelectronic integrated chip for transmission of electrical signals.

9. The testing device according to claim 8, It is characterized in that The output wavelength of the tunable polarization-maintaining light source is continuously adjusted within the wavelength range of a preset band; The preset band is O band or C band; The tunable polarization-maintaining light source outputs polarization-maintaining light of a single wavelength or outputs polarization-maintaining light of a swept wavelength; The polarization-maintaining light is connected to the 1×2-way polarization-maintaining optical switch through a polarization-maintaining optical fiber, and the polarization state is kept unchanged.

10. The testing device according to claim 9, It is characterized in that The operating wavelength range of the 1×2 polarization-maintaining optical switch, the first polarization-maintaining optical splitter, the second polarization-maintaining optical splitter, the at least two polarization-maintaining optical circulators and the multi-channel optical power meter at least includes the wavelength range of the preset band; The polarization state of the polarization-maintaining light passing through the 1×2 polarization-maintaining optical switch, the first polarization-maintaining optical splitter, the second polarization-maintaining optical splitter, and at least two polarization-maintaining optical circulators remains unchanged.

11. A silicon-based optoelectronic integrated chip, wherein the silicon-based optoelectronic integrated chip is connected to a testing device according to any one of claims 1 to 10 to measure optical parameters. It is characterized in that The silicon-based optoelectronic integrated chip comprises: An input port, the number of the input port is one, configured to be aligned with the channel of the single-channel array and receive polarization-maintaining light from the first optical coupling link; A light splitting monitoring module is configured to receive the polarization-maintaining light passing through the input port, and to split the polarization-maintaining light into N light paths and then monitor the input optical power of each light path through an input monitoring detector; An optical modulation module, configured to receive N optical beams from the optical splitting monitoring module and output them after dimming; An output monitoring module is configured to receive N light paths after dimming from the optical modulation module and monitor the output optical power of each light path through an output monitoring detector; The output ports are N in number and are configured to be aligned one-to-one with the N channels of the multi-channel array, and to input polarization-maintaining light into the second optical coupling link and non-polarization-maintaining light into the corresponding channels of the multi-channel optical power meter through the multi-channel array.

12. The silicon-based optoelectronic integrated chip according to claim 11, It is characterized in that The spectroscopic monitoring module comprises: A cascaded first optical splitter configured to split a beam of polarization-maintaining light received by the input port into N optical paths; The N input monitoring detectors arranged on the N light paths are configured to monitor the input optical power of each corresponding light path.

13. The silicon-based optoelectronic integrated chip according to claim 12, It is characterized in that The optical modulation module comprises: N second optical splitters, configured to split each of the N optical paths into two optical paths, to obtain 2N optical paths; 2N silicon optical modulators disposed on the 2N optical paths, configured to dim each optical path; N phase shifters are correspondingly arranged on one of the light paths of every two light paths after dimming; N optical combiners are arranged after the N phase shifters, and are configured to combine every two light paths to obtain N modulated light paths.

14. A method for testing a silicon-based optoelectronic integrated chip, comprising: using a testing device according to any one of claims 1 to 10 to test the optical parameters of the silicon-based optoelectronic integrated chip according to any one of claims 11 to 13, wherein the testing method The following steps are involved: Use the first optical coupling link to build an optical power ratio measurement link to obtain the optical power splitting ratio of the polarization-maintaining light output by the tunable polarization-maintaining light source at the output end and at the monitoring end; Connect the electrical parameter measurement link, use a multi-channel digital source meter to provide operating voltage to the silicon-based optoelectronic integrated chip through the probe card and measure the current; Using the first optical coupling link to calibrate the position of the single-channel array so that its channel is aligned with the input port of the silicon-based optoelectronic integrated chip; Using a second optical coupling link to calibrate the position of the multi-channel array so that its N channels are respectively aligned with the N output ports of the corresponding silicon-based optoelectronic integrated chip; Control the tunable light source to output polarization-maintaining light of a fixed wavelength, and use the optical parameter measurement link and the electrical parameter measurement link to test the minimum optical loss and phase shifter voltage operating point of the N channels of the silicon-based optoelectronic integrated chip; The tunable light source is controlled to output polarization-maintaining light with swept wavelength, and the optical parameter measurement link and the electrical parameter measurement link are used to test the light response of the silicon-based optoelectronic integrated chip.

15. The test method according to claim 14, It is characterized in that The step of using the first optical coupling link to construct an optical power ratio measurement link specifically includes: Connect one of the polarization-maintaining lights output by the first polarization-maintaining light splitter to channel 1 of the multi-channel optical power meter as a monitoring end optical path; Connect another polarization-maintaining light output by the first polarization-maintaining light splitter to channel N+2 of the multi-channel optical power meter as an output end optical path; When the tunable polarization-maintaining light source outputs swept wavelength polarization-maintaining light, the optical power ratio of the output end optical path and the monitoring end optical path is measured at each wavelength point within the swept wavelength range.

16. The test method according to claim 14, It is characterized in that The steps of connecting the electrical parameter measurement link and using a multi-channel digital source meter to provide an operating voltage to the silicon-based optoelectronic integrated chip through a probe card and measure the current specifically include: Turn off the tunable polarization-maintaining light source through the control module; The control module controls the multi-channel digital source meter to apply a working voltage signal to all input monitoring detectors and output monitoring detectors in the silicon-based optoelectronic integrated chip through the probe card; Measure the dark current corresponding to all input monitoring detectors and output monitoring detectors.

17. The testing method according to claim 14, It is characterized in that In the step of calibrating the position of the single-channel array using the first optical coupling link, the position of the single-channel array is adjusted according to the change of the photocurrent of any input monitoring detector of the optical splitting monitoring module in the silicon-based optoelectronic integrated chip; When the photocurrent of any input monitoring detector reaches a maximum value, the single-channel array is aligned with the input port of the silicon-based optoelectronic integrated chip.

18. The testing method according to claim 14, It is characterized in that In the step of calibrating the position of the multi-channel array using the second optical coupling link, the position of the multi-channel array is adjusted according to changes in photocurrents of output monitoring detectors corresponding to the first polarization-maintaining light receiving port and the second polarization-maintaining light receiving port in the output monitoring module in the silicon-based optoelectronic integrated chip; When it is monitored that the photocurrents of the first polarization-maintaining light receiving port and the second polarization-maintaining light receiving port reach a balanced maximum value, the multi-channel array is aligned with the output port of the silicon-based optoelectronic integrated chip.

19. The test method according to any one of claims 14 to 18, It is characterized in that The steps of controlling the tunable light source to output polarization-maintaining light of a fixed wavelength and using an optical parameter measurement link and an electrical parameter measurement link to test the minimum optical loss and the phase shifter voltage operating point of N channels of the silicon-based optoelectronic integrated chip specifically include: Controlling the tunable light source to output polarization-maintaining light of a corresponding preset optical power at a preset wavelength point; Control the multi-channel digital source meter to apply the working voltage to N phase shifters in the silicon-based optoelectronic integrated chip through the probe card and measure the working current corresponding to the N phase shifters to obtain the voltage and current characteristics of the phase shifters; Collecting the variation curves of the photocurrents of N output monitoring detectors corresponding to the N phase shifters and the thermal powers of the N phase shifters; Collect and record the optical powers corresponding to the N output ports of the silicon-based optoelectronic integrated chip under the thermal powers of the N phase shifters in the corresponding channels of the multi-channel optical power meter, and obtain the variation curve of the on-chip loss of the N output ports of the silicon-based optoelectronic integrated chip with the thermal powers of the N phase shifters; The maximum optical power on the curve of on-chip loss of each output port of the silicon-based optoelectronic integrated chip varying with the thermal power of the corresponding phase shifter is the minimum loss of the output port at the preset wavelength point, and the phase shifter voltage corresponding to the minimum loss is the phase shifter voltage operating point.

20. The test method according to claim 19, It is characterized in that The steps of controlling the tunable light source to output polarization-maintaining light with a swept wavelength and using an optical parameter measurement link and an electrical parameter measurement link to test the light responsivity of the silicon-based optoelectronic integrated chip specifically include: The operating voltages of the N phase shifters in the silicon-based optoelectronic integrated chip are respectively set to the voltages applied to the corresponding N channels when the minimum on-chip loss is obtained at the preset wavelength point; Controlling the tunable light source to output wavelength-swept polarization-maintaining light within a preset wavelength band; Control the multi-channel digital source meter to measure the photocurrent of all input monitoring detectors and output monitoring detectors in the silicon-based optoelectronic integrated chip through the probe card; Calculate the photoresponsivity curve of each input monitoring detector through the photocurrent and dark current corresponding to each input monitoring detector; The photoresponsivity curve of each output monitoring detector is calculated by the photocurrent and dark current corresponding to each output monitoring detector.

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