Method and apparatus for measuring opto-electric s-parameters of an opto-electric converter

Abstract

The application relates to the technical field of measurement and provides a method and device for measuring photoelectric S parameters of a photoelectric converter. The method comprises the following steps: generating an input voltage signal by a vector network analyzer, and modulating an optical signal provided by a light source in an optical signal generation module according to the input voltage signal to obtain a modulated optical signal by the optical signal generation module; receiving the modulated optical signal by a to-be-measured photoelectric converter and providing an output voltage signal corresponding to the modulated optical signal; and comparing the input voltage signal and the output voltage signal by the vector network analyzer to obtain photoelectric S parameters of the to-be-measured photoelectric converter. Thus, the measurement process is simplified and the measurement precision is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of measurement, in particular to a method and device for measuring photoelectric S parameters of a photoelectric converter. BACKGROUND

[0002] In the application scenarios of optical communication and optoelectronic devices, it is often necessary to convert the received optical signal into a weak current signal through a photodiode (PD), and then convert the current signal into a voltage signal through a trans-impedance amplifier (TIA). Because it involves the conversion from an optical signal to an electrical signal, the joint response of the photodiode and the trans-impedance amplifier corresponds to the photoelectric scattering parameter. The scattering parameter is the scatter parameter, which can be referred to as the S parameter. The S parameter is generally used to describe the incidence, reflection and transmission characteristics of signals in a circuit, and provides a simplified circuit characterization method by analyzing the behavior of signals at different ports. Here, the S parameter measurement from the input of an optical signal to the output of an electrical signal corresponds to the photoelectric S parameter, which is used to describe the frequency response characteristics of an optoelectronic device, and can be realized by measuring the frequency-dependent transfer characteristics of an optoelectronic device from the input of an optical signal to the output of an electrical signal. However, the trans-impedance amplifier has the characteristics that the input signal is a current signal and the output signal is a voltage signal, so it cannot directly use the measurement method based on the voltage signal. In addition, the trans-impedance amplifier needs to meet the requirements of low input impedance, low noise and wide frequency band according to the design requirements, so it is applied in photoelectric detectors, sensor interfaces, weak current signal amplification (such as optical communication, medical equipment, particle detection, etc.). The existing measurement scheme of the photoelectric S parameter directly measures the electrical signal bandwidth and trans-impedance gain of the trans-impedance amplifier to obtain the electrical S parameter of the trans-impedance amplifier, and then simulates the electrical S parameter of the trans-impedance amplifier and the parasitic parameters extracted from the photodiode and the bond wire connected between the two to obtain the gain and bandwidth of the photoelectric conversion device including the photodiode, the bond wire and the trans-impedance amplifier. Here, the bond wire, also known as the wire, refers to the establishment of an electrical circuit connection for the transmission path of an electrical signal through a wire bounding process in integrated circuit packaging, such as the establishment of an electrical circuit connection between a die and a lead frame. Therefore, the existing measurement scheme of the photoelectric S parameter for the photoelectric converter (such as a photoelectric converter including a photodiode, a bond wire and a trans-impedance amplifier, an optical receiver, etc.) is relatively complex in terms of process, which needs to measure the electrical S parameter of the trans-impedance amplifier first, and then simulate the electrical S parameter of the trans-impedance amplifier and the parasitic parameters extracted from the photodiode and the bond wire connected between the two, and the measurement effect depends on the extraction and simulation effect of the parasitic parameters, which may result in low measurement accuracy.

[0003] To this end, the present application provides a method and device for measuring photoelectric S parameters of photoelectric converters, which are used to solve the technical problems in the prior art. SUMMARY

[0004] In a first aspect, the present application provides a method for measuring photoelectric S parameters of photoelectric converters. The method comprises: generating an input voltage signal by a vector network analyzer, and modulating an optical signal provided by a light source in an optical signal generation module according to the input voltage signal by the optical signal generation module, so as to obtain a modulated optical signal; receiving the modulated optical signal by a to-be-measured photoelectric converter and providing an output voltage signal corresponding to the modulated optical signal; and comparing the input voltage signal and the output voltage signal by the vector network analyzer, so as to obtain the photoelectric S parameters of the to-be-measured photoelectric converter. Wherein, the to-be-measured photoelectric converter comprises a photodiode and a trans-impedance amplifier, the photodiode is used to convert the modulated optical signal into an input current signal, the trans-impedance amplifier is used to convert the input current signal into the output voltage signal, the anode of the photodiode is connected to the input end of the trans-impedance amplifier through a first wire, the cathode of the photodiode is used to connect a power supply, and a capacitor array comprising at least one capacitor is connected in parallel between the cathode of the photodiode and the ground end of the trans-impedance amplifier, the optimal combination of the length and diameter of the first wire is determined based on the type of the photodiode and the circuit design of the trans-impedance amplifier, the total capacitance value of the capacitor array is adjusted to adapt to the current combination of the length and diameter of the first wire, so as to adjust the system response curve associated with the current combination of the length and diameter of the first wire to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire.

[0005] By the first aspect of the present application, a measurement scheme for measuring photoelectric S parameters of a to-be-measured photoelectric converter and directly measuring parameters such as bandwidth and gain is provided by using a vector network analyzer and an optical signal generation module, thereby saving the loss of joint simulation and parasitic parameter extraction; and the influence of wire bonding and parasitic parameters on the bandwidth of a transimpedance amplifier and the overall bandwidth of a photoelectric conversion device is considered, a coarse adjustment mode is provided by using the combination of the length and diameter of a first wire, a fine adjustment mode is provided by using the adjustability of the total capacitance value of a capacitance array, and the optimal combination of the length and diameter of the first wire is determined based on the type of the photodiode and the circuit design of the transimpedance amplifier, the system response curve associated with the current combination of the length and diameter of the first wire is adjusted so as to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire, the type of the photodiode and the circuit design of the transimpedance amplifier are adapted, the system response curve is optimized, the frequency domain response characteristics of high bandwidth and in-band gain flatness are realized, the influence of parasitic parameters on the measurement result is reduced, and the measurement accuracy is improved.

[0006] In a possible implementation manner of the first aspect of the present application, the first wire is used to provide a signal transmission path between the photodiode and the transimpedance amplifier, and the capacitance array is used to provide a coupling-to-ground path parallel to the signal transmission path.

[0007] In a possible implementation manner of the first aspect of the present application, the inductive coupling of the first wire is used to optimize the bandwidth of the to-be-measured photoelectric converter, and the capacitance array is used to optimize the flatness of the in-band gain of the to-be-measured photoelectric converter.

[0008] In a possible implementation manner of the first aspect of the present application, the capacitance array includes an adjustable capacitance, and the total capacitance value of the adjustable capacitance is adjusted to adjust the total capacitance value of the capacitance array.

[0009] In a possible implementation manner of the first aspect of the present application, the at least one capacitance is selectively connected to the capacitance array by a switchable switch, thereby adjusting the total capacitance value of the capacitance array.

[0010] In a possible implementation manner of the first aspect of the present application, the system response curve associated with the optimal combination of the length and diameter of the first wire indicates that when the current combination of the length and diameter of the first wire in the to-be-measured photoelectric converter adopts the optimal combination of the length and diameter of the first wire, the bandwidth and the flatness of the in-band gain of the to-be-measured photoelectric converter are optimized.

[0011] In a possible implementation form of the first aspect of the application, the adjustment direction of the total capacitance value of the capacitance array indicates an adjustment direction of the current combination of the length and diameter of the first wire with respect to an optimal combination of the length and diameter of the first wire.

[0012] In a possible implementation form of the first aspect of the application, the welding manner of the first wire is ball bonding or wedge bonding.

[0013] In a possible implementation form of the first aspect of the application, the total capacitance value of the capacitance array is adjusted so as to adjust a system response curve associated with the current combination of the length and diameter of the first wire, thereby improving the bandwidth and the flatness of the in-band gain of the photoelectric transducer under test.

[0014] In a possible implementation form of the first aspect of the application, the photoelectric S parameter of the photoelectric transducer under test is a photoelectric scattering parameter corresponding to a joint response of the photodiode and the transimpedance amplifier, the photoelectric S parameter of the photoelectric transducer under test before adjustment is used to determine a system response curve associated with the current combination of the length and diameter of the first wire before adjustment, and the photoelectric S parameter of the photoelectric transducer under test after adjustment is used to determine a system response curve associated with the current combination of the length and diameter of the first wire after adjustment.

[0015] In a possible implementation form of the first aspect of the application, the adjustability of the total capacitance value of the capacitance array is used together with the adjustability of the current combination of the length and diameter of the first wire to provide an adjustability of a bridge waveguide corresponding to the first wire, the adjustability of the bridge waveguide is utilized to determine a wire bonding scheme adapted to the type of the photodiode and the circuit design of the transimpedance amplifier, or the adjustability of the bridge waveguide is utilized to conduct a wire bonding scheme hybrid test together with the circuit design of the transimpedance amplifier.

[0016] In a second aspect, the present application provides a device for measuring opto-electric S-parameters of an opto-electric converter. The device comprises a vector network analyzer configured to generate an input voltage signal; and an optical signal generation module configured to modulate an optical signal provided by a light source in the optical signal generation module according to the input voltage signal, thereby obtaining a modulated optical signal, wherein the modulated optical signal is received by the opto-electric converter to be measured and an output voltage signal corresponding to the modulated optical signal is provided. The vector network analyzer is further configured to compare the input voltage signal and the output voltage signal, thereby obtaining the opto-electric S-parameters of the opto-electric converter to be measured. The opto-electric converter to be measured comprises a photodiode configured to convert the modulated optical signal into an input current signal, and a trans-impedance amplifier configured to convert the input current signal into the output voltage signal. An anode of the photodiode is connected to an input of the trans-impedance amplifier through a first wire, a cathode of the photodiode is configured to be connected to a power supply, and a capacitor array comprising at least one capacitor is connected in parallel between the cathode of the photodiode and a ground of the trans-impedance amplifier. An optimal combination of a length and a diameter of the first wire is determined based on a type of the photodiode and a circuit design of the trans-impedance amplifier, and a total capacitance value of the capacitor array is adjusted to adapt to a current combination of the length and the diameter of the first wire, thereby adjusting a system response curve associated with the current combination of the length and the diameter of the first wire to approximate a system response curve associated with the optimal combination of the length and the diameter of the first wire.

[0017] By the second aspect of the present application, the vector network analyzer and the optical signal generation module are used to provide a measurement scheme for measuring the opto-electric S-parameters of the opto-electric converter to be measured and directly measuring parameters such as bandwidth and gain, thereby saving the loss of joint simulation and parasitic parameter extraction. Moreover, the influence of the wire and the parasitic parameters on the bandwidth of the trans-impedance amplifier and the overall bandwidth of the opto-electric converter is considered, the combination of the length and the diameter of the first wire is used to provide a coarse adjustment mode, the adjustability of the total capacitance value of the capacitor array is used to provide a fine adjustment mode, the optimal combination of the length and the diameter of the first wire is determined based on the type of the photodiode and the circuit design of the trans-impedance amplifier, the system response curve associated with the current combination of the length and the diameter of the first wire is adjusted to approximate the system response curve associated with the optimal combination of the length and the diameter of the first wire, thereby adapting to the type of the photodiode and the circuit design of the trans-impedance amplifier, optimizing the system response curve, achieving the frequency domain response characteristics of high bandwidth and gain flatness within the bandwidth, reducing the influence of the parasitic parameters on the measurement results, and improving the measurement accuracy.

[0018] In a possible implementation manner of the second aspect of the present application, the system response curve related to the optimal combination of the length and diameter of the first wire indicates that the bandwidth and the flatness of the in-band gain of the to-be-tested photoelectric converter are optimized when the current combination of the length and diameter of the first wire in the to-be-tested photoelectric converter adopts the optimal combination of the length and diameter of the first wire.

[0019] In a possible implementation manner of the second aspect of the present application, the adjustment direction of the total capacitance value of the capacitance array indicates the adjustment direction of the current combination of the length and diameter of the first wire relative to the optimal combination of the length and diameter of the first wire.

[0020] In a possible implementation manner of the second aspect of the present application, the adjustability of the total capacitance value of the capacitance array and the adjustability of the current combination of the length and diameter of the first wire are used together to provide the adjustability of the bridge waveguide corresponding to the first wire, and the adjustability of the bridge waveguide is used to determine the wire scheme adapted to the type of the photodiode and the circuit design of the trans-impedance amplifier, or the adjustability of the bridge waveguide is used to perform the wire scheme mixed test together with the circuit design of the trans-impedance amplifier. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0022] Figure 1 A flowchart of a method for measuring photoelectric S parameters of a photoelectric converter provided by an embodiment of the present application;

[0023] Figure 2 A schematic diagram of a device for measuring photoelectric S parameters of a photoelectric converter provided by an embodiment of the present application;

[0024] Figure 3 A schematic diagram of multiple wire schemes provided by an embodiment of the present application. DETAILED DESCRIPTION

[0025] The embodiments of the present application will be further described in detail below with reference to the drawings.

[0026] It should be understood that in the description of the application, "at least one" means one or more, and "multiple" means two or more. In addition, the words "first", "second", and the like, unless otherwise specified, are only used to distinguish the description purpose, and cannot be understood as indicating or implying relative importance, nor can it be understood as indicating or implying order.

[0027] Figure 1 A flowchart of a measurement method for optoelectronic S parameters of an optoelectronic converter is provided for an embodiment of the present application. As shown in Figure 1 , the measurement method comprises the following steps.

[0028] Step S101: generating an input voltage signal by a vector network analyzer, and modulating an optical signal provided by a light source in an optical signal generation module according to the input voltage signal by the optical signal generation module, thereby obtaining a modulated optical signal.

[0029] Step S103: receiving the modulated optical signal by the to-be-measured optoelectronic converter and providing an output voltage signal corresponding to the modulated optical signal.

[0030] Step S105: comparing the input voltage signal and the output voltage signal by the vector network analyzer, thereby obtaining the optoelectronic S parameters of the to-be-measured optoelectronic converter.

[0031] Figure 1 As shown in the measurement method, the to-be-measured optoelectronic converter includes a photodiode and a transimpedance amplifier, the photodiode is used to convert the modulated optical signal into an input current signal, the transimpedance amplifier is used to convert the input current signal into the output voltage signal, the anode of the photodiode is connected to the input end of the transimpedance amplifier through a first wire, the cathode of the photodiode is used to connect a power supply, and a capacitor array including at least one capacitor is connected in parallel between the cathode of the photodiode and the ground end of the transimpedance amplifier, the optimal combination of the length and diameter of the first wire is determined based on the type of the photodiode and the circuit design of the transimpedance amplifier, the total capacitance value of the capacitor array is adjusted to adapt to the current combination of the length and diameter of the first wire, thereby adjusting the system response curve associated with the current combination of the length and diameter of the first wire to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire.

[0032] Referring to Figure 1At step S101, an input voltage signal is generated by a vector network analyzer, and an optical signal provided by a light source in an optical signal generation module is modulated according to the input voltage signal to obtain a modulated optical signal. At step S103, the modulated optical signal is received by a photoelectric converter under test, and an output voltage signal corresponding to the modulated optical signal is provided. At step S105, the input voltage signal and the output voltage signal are compared by the vector network analyzer to obtain photoelectric S parameters of the photoelectric converter under test. In this way, the vector network analyzer and the optical signal generation module constitute a hardware part for measuring photoelectric S parameters of the photoelectric converter under test. The vector network analyzer generates the input voltage signal and receives the output voltage signal, compares the input voltage signal and the output voltage signal, analyzes and calculates to obtain the photoelectric S parameters of the photoelectric converter under test, so as to evaluate and analyze the performance of the device. The vector network analyzer can be, for example, an instrument for measuring radio frequency and microwave signals, and can be used to measure S parameters of a device including amplitude and phase responses. The vector network analyzer can include a signal source for generating a radio frequency signal (corresponding to the input voltage signal) inside, a test port for connecting the device, a receiving port for receiving an output signal (corresponding to the output voltage signal) from the device, a processor for performing mathematical processing and network parameter calculation on the signal, and a display for displaying the measurement results or a display port for transmitting the measurement results. The light source in the optical signal generation module provides a stable optical signal, which can optionally match the working wavelength of the photoelectric converter under test. The light source can be, for example, a continuous wave (CW) laser, which can realize stable laser output through continuous excitation energy. Generally, the continuous wave laser has a lower peak power and a higher average power. It should be understood that any suitable light source or type of light source can be used as long as it meets the requirements of photoelectric S parameter measurement. The optical signal generation module can include a necessary driver and modulator. The driver, or driving unit, is used to drive the modulator from the outside, so that the light source provides an optical signal modulated by the modulator to contain a radio frequency signal. In some embodiments, the driver is used to receive a radio frequency signal and generate a modulation signal of the modulator based on the radio frequency signal, so that the modulator can modulate the optical signal based on the modulation signal to obtain a modulated optical signal. In this way, the optical signal provided by the light source in the optical signal generation module is modulated according to the input voltage signal to obtain a modulated optical signal. The modulator can be, for example, a Mach-Zehnder modulator (MZM).Here, the operating principle of the Mach-Zehnder modulator is generally to divide the input optical signal into two equal signals, which are respectively input into two optical branches, and an electro-optic material is used in the two optical branches, so that the refractive index changes with the size of the externally applied electrical signal (radio frequency signal). Thus, because the refractive index of the optical branch changes, the phase of the signal changes, so when the optical signals output by the two optical branches are combined together again, the combined optical signal will be an interference signal with varying intensity, which is equivalent to converting the change of the electrical signal into the change of the optical signal, thereby realizing the modulation of the optical intensity. By using a Mach-Zehnder modulator or other suitable optical signal modulation method, the change of the electrical signal can be loaded onto the optical signal, that is, the optical signal provided by the light source in the optical signal generating module is modulated according to the input voltage signal, thereby obtaining a modulated optical signal.

[0033] With reference to the accompanying drawings Figure 1The to-be-tested photoelectric converter includes a photodiode and a trans-impedance amplifier, the photodiode is configured to convert the modulated optical signal into an input current signal, and the trans-impedance amplifier is configured to convert the input current signal into the output voltage signal, the anode of the photodiode is connected to the input end of the trans-impedance amplifier through a first bond wire, and the cathode of the photodiode is configured to be connected to a power supply. In some embodiments, the power supply is inside the to-be-tested photoelectric converter; in other embodiments, the power supply can be outside the to-be-tested photoelectric converter, or the power supply can be provided separately, that is, not as part of the to-be-tested photoelectric converter. In addition, the power supply is configured to provide a working bias voltage for the photodiode, therefore, any circuit or device having a biasing function can replace the power supply, as long as the photodiode can work in a suitable bias state so that the photodiode is configured to convert the modulated optical signal into an input current signal. Thus, the to-be-tested photoelectric converter represents any photoelectric device or photoelectric system having a photoelectric conversion function. For example, in the application scenarios of optical communication and photoelectric devices, a photodiode (PD) is used to convert the received optical signal into a weak current signal, and then a trans-impedance amplifier (TIA) is used to convert the current signal into a voltage signal. Here, because the conversion from an optical signal to an electrical signal is involved, the S-parameter measurement from the optical signal input to the electrical signal output corresponds to the photoelectric S-parameter, which is used to describe the frequency response characteristics of the photoelectric device and can be realized by measuring the frequency-dependent transmission characteristics of the photoelectric device from the optical signal input to the electrical signal output. Considering that the trans-impedance amplifier has the characteristics that the input signal is a current signal and the output signal is a voltage signal, the measurement method based on the voltage signal cannot be directly used. In addition, the influence of parasitic parameters such as parasitic capacitance needs to be considered. Here, the anode of the photodiode is connected to the input end of the trans-impedance amplifier through a first bond wire. The first bond wire is a bond wire, also known as a bonding wire. The bond wire refers to the establishment of a circuit connection through a wire bounding process in an integrated circuit package for the transmission path of an electrical signal. By using the above hardware part for measuring the photoelectric S-parameter of the to-be-tested photoelectric converter, that is, the vector network analyzer and the optical signal generation module, the bandwidth and gain of the to-be-tested photoelectric converter can be determined by the vector network analyzer, without separately measuring the S-parameter of the trans-impedance amplifier, but by modulating the radio frequency signal onto the optical signal through a modulator such as an MZM, joint simulation is not required, and the bandwidth and gain of the to-be-tested photoelectric converter can be directly measured. For example, by using the characteristic that the refractive index can be changed according to the high-frequency electrical signal in the MZM, the high-frequency electrical signal is loaded onto the amplitude of the optical intensity, and high-speed modulation is realized.Further, in order to overcome the influence of the parasitic parameters, specifically, in order to overcome the influence of the parasitic parameters of the wire bonding and the front-stage photodiode on the bandwidth of the transimpedance amplifier and the overall bandwidth of the photoelectric conversion device, by using the parameters of the length and width (diameter) of the metal lead that can be set in the wire bonding technology, by selecting different wire bonding schemes, for example, by combining different lengths and widths (diameters), optimization is performed for specific photodiodes and specific transimpedance amplifiers, so that a high bandwidth and a gain flat frequency domain response characteristic within the bandwidth are achieved. In addition, for specific transimpedance amplifiers, a hybrid test of different photodiode types and different wire bonding schemes can be performed to select the optimal photodiode type and the corresponding optimal wire bonding scheme. In addition, when the transimpedance amplifier is also not specific, the optimal transimpedance amplifier, the optimal photodiode, and the corresponding optimal wire bonding scheme can be selected in combination with the application scenario and the bandwidth and gain requirements.

[0034] With reference to the accompanying drawings Figure 1, in order to simplify the measurement process and improve the measurement accuracy in measuring the optoelectronic S parameters of the to-be-measured optoelectronic converter, it is necessary to avoid the additional loss of joint simulation and parasitic parameter extraction, and to realize the direct measurement of the bandwidth and gain of the to-be-measured optoelectronic converter by utilizing the optimized design of the hardware part. Moreover, the influence of the wire and parasitic parameters on the bandwidth of the transimpedance amplifier and the overall bandwidth of the optoelectronic device needs to be considered. In order to achieve a high bandwidth and a flat gain within the bandwidth of the frequency domain response characteristics to improve the measurement effect, a coarse adjustment method is provided by the combination of the length and diameter (corresponding to the width) of the first wire, and a fine adjustment method is provided by the capacitance array. The type of photodiode and the circuit design of the transimpedance amplifier are adapted to optimize the system response curve, achieve a high bandwidth and a flat gain within the bandwidth of the frequency domain response characteristics, reduce the influence of parasitic parameters on the measurement results, and improve the measurement accuracy. Specifically, the capacitance array including at least one capacitor is connected in parallel between the cathode of the photodiode and the ground terminal of the transimpedance amplifier. The optimal combination of the length and diameter of the first wire is determined based on the type of photodiode and the circuit design of the transimpedance amplifier. The total capacitance value of the capacitance array is adjusted to adapt to the current combination of the length and diameter of the first wire, so as to adjust the system response curve associated with the current combination of the length and diameter of the first wire to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire. In this way, the anode of the photodiode is connected to the input terminal of the transimpedance amplifier through the first wire, which means that the first wire provides a signal transmission path for signal transmission from the photodiode to the transimpedance amplifier. By utilizing the connection relationship of the capacitance array and the adjustability of the total capacitance value of the capacitance array, the capacitance array is connected in parallel between the cathode of the photodiode and the ground terminal of the transimpedance amplifier, which means that the capacitance array provides a ground coupling path parallel to the signal transmission path, so that the inductive coupling of the wire bonding (or wire bonding) can be designed as a bridge waveguide, which is conducive to reducing the signal distortion of a single wire. Moreover, the inductive coupling of the first wire can optimize the system bandwidth, and the adjustment of the total capacitance value of the capacitance array can optimize the flatness of the gain within the bandwidth. The current combination of the length and diameter of the first wire indicates the current length and diameter (corresponding to the width of the first wire) of the first wire, and the optimal combination of the length and diameter of the first wire can be determined based on the type of photodiode and the circuit design of the transimpedance amplifier, i.e. the optimal wire solution needs to be provided to adapt to the type of photodiode and the circuit design of the transimpedance amplifier.Thus, the coarse adjustment manner is provided by the combination of the length and the diameter of the first wire, i.e. the coarse adjustment manner is provided by the current combination of the length and the diameter of the first wire, so that the system response curve associated with the current combination of the length and the diameter of the first wire is set as a starting state, then the total capacitance value of the capacitance array is adjusted to optimize the system response curve including optimizing the flatness of the in-band gain, so that the system response curve associated with the optimal combination of the length and the diameter of the first wire is set as a target state, and the total capacitance value of the capacitance array is adjusted to adjust the system response curve associated with the current combination of the length and the diameter of the first wire to approximate the system response curve associated with the optimal combination of the length and the diameter of the first wire. Therefore, on the basis of providing the coarse adjustment manner by the combination of the length and the diameter of the first wire (corresponding to the width of the first wire), the fine adjustment manner is provided by the capacitance array, so that the system response curve associated with the current combination of the length and the diameter of the first wire (i.e. the starting state) is adjusted to approximate the system response curve associated with the optimal combination of the length and the diameter of the first wire (i.e. the target state). Thus, the coarse adjustment manner is provided by the combination of the length and the diameter of the first wire, and the fine adjustment manner is provided by the adjustability of the total capacitance value of the capacitance array, and the optimal combination of the length and the diameter of the first wire is determined based on the type of the photodiode and the circuit design of the transimpedance amplifier, the system response curve associated with the current combination of the length and the diameter of the first wire is adjusted to approximate the system response curve associated with the optimal combination of the length and the diameter of the first wire, so that the type of the photodiode and the circuit design of the transimpedance amplifier are adapted, the system response curve is optimized, the frequency domain response characteristic of high bandwidth and in-band gain flatness is achieved, the influence of the parasitic parameters on the measurement result is reduced, and the measurement accuracy is improved.

[0035] In summary, Figure 1The measurement method shown utilizes a vector network analyzer and an optical signal generation module to provide a measurement scheme for measuring the optoelectronic S parameters of the to-be-measured optoelectronic converter and directly measuring parameters such as bandwidth and gain, thereby saving the loss of joint simulation and parasitic parameter extraction; and, the influence of wire bonding and parasitic parameters on the bandwidth of the transimpedance amplifier and the overall bandwidth of the optoelectronic converter is considered, the length and diameter of the first wire are combined to provide a coarse adjustment mode, the total capacitance value of the capacitor array is adjustable to provide a fine adjustment mode, and the optimal combination of the length and diameter of the first wire is determined based on the type of the photodiode and the circuit design of the transimpedance amplifier, the system response curve associated with the current combination of the length and diameter of the first wire is adjusted to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire, the type of the photodiode and the circuit design of the transimpedance amplifier are adapted, the system response curve is optimized, the frequency domain response characteristics of high bandwidth and in-band gain flatness are achieved, the influence of parasitic parameters on the measurement result is reduced, and the measurement accuracy is improved.

[0036] Reference Figure 1 In a possible implementation, the first wire is used to provide a signal transmission path between the photodiode and the transimpedance amplifier, and the capacitor array is used to provide a ground coupling path parallel to the signal transmission path. In this way, the anode of the photodiode is connected to the input end of the transimpedance amplifier through the first wire, which means that the first wire provides a signal transmission path for signal transmission from the photodiode to the transimpedance amplifier; the capacitor array is connected in parallel between the cathode of the photodiode and the ground end of the transimpedance amplifier by using the connection relationship of the capacitor array and the adjustability of the total capacitance value of the capacitor array, which means that the capacitor array provides a ground coupling path parallel to the signal transmission path, so that the inductive coupling of the wire bonding (or wire bonding) can be designed as a bridge waveguide, which is conducive to reducing the signal distortion of a single wire, and the inductive coupling of the first wire can optimize the system bandwidth and the adjustment of the total capacitance value of the capacitor array can optimize the flatness of the in-band gain.

[0037] In some embodiments, the inductive coupling of the first wire is used to optimize the bandwidth of the photovoltaic converter under test, and the capacitance array is used to optimize the flatness of the gain within the bandwidth of the photovoltaic converter under test. Thus, the combination of the length and diameter (corresponding to the width) of the first wire provides a coarse adjustment manner, i.e., the current combination of the length and diameter of the first wire sets the system response curve associated with the current combination of the length and diameter of the first wire as a starting state, and then the total capacitance value of the capacitance array is adjusted to optimize the system response curve, including optimizing the flatness of the gain within the bandwidth, so as to achieve the system response curve associated with the optimal combination of the length and diameter of the first wire as a target state, and the total capacitance value of the capacitance array is adjusted to adjust the system response curve associated with the current combination of the length and diameter of the first wire so as to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire. Therefore, on the basis of providing a coarse adjustment manner by the combination of the length and diameter (corresponding to the width) of the first wire, a fine adjustment manner is achieved by the capacitance array, so as to approach the target state from the starting state, i.e., the system response curve associated with the current combination of the length and diameter of the first wire, i.e., the system response curve associated with the current combination of the length and diameter of the first wire is adjusted to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire.

[0038] In a possible implementation, the capacitance array includes an adjustable capacitance, and the total capacitance value of the adjustable capacitance is adjusted to adjust the total capacitance value of the capacitance array. Thus, with the adjustable capacitance, the total capacitance value of the capacitance array is adjusted to optimize the system response curve, including optimizing the flatness of the gain within the bandwidth, so as to achieve the system response curve associated with the optimal combination of the length and diameter of the first wire as a target state, and the total capacitance value of the capacitance array is adjusted to adjust the system response curve associated with the current combination of the length and diameter of the first wire so as to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire. Therefore, on the basis of providing a coarse adjustment manner by the combination of the length and diameter (corresponding to the width) of the first wire, a fine adjustment manner is achieved by the capacitance array, so as to approach the target state from the starting state, i.e., the system response curve associated with the current combination of the length and diameter of the first wire, i.e., the system response curve associated with the current combination of the length and diameter of the first wire is adjusted to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire.

[0039] In one possible implementation, the at least one capacitor is each selectively accessed to the capacitor array by a switchable switch to adjust the total capacitance value of the capacitor array. In this way, the at least one capacitor can be accessed or not accessed to the capacitor array by the switchable switch, so that the total capacitance value of the capacitor array is adjusted to optimize the system response curve including optimizing the flatness of the in-band gain, so as to achieve the system response curve associated with the optimal combination of the length and diameter of the first wire as the target state, and adjust the system response curve associated with the current combination of the length and diameter of the first wire to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire by adjusting the total capacitance value of the capacitor array. Therefore, on the basis of providing a coarse adjustment mode by the combination of the length and diameter (corresponding to the width of the first wire) of the first wire, a fine adjustment mode is achieved by the capacitor array, so as to approach the target state from the starting state, i.e., the system response curve associated with the current combination of the length and diameter of the first wire, i.e., adjust the system response curve associated with the current combination of the length and diameter of the first wire to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire.

[0040] In one possible implementation, the system response curve associated with the optimal combination of the length and diameter of the first wire indicates that when the current combination of the length and diameter of the first wire in the to-be-tested photoelectric converter matches the optimal combination of the length and diameter of the first wire, the bandwidth and the flatness of the in-band gain of the to-be-tested photoelectric converter are optimized. In this way, by setting the length and width parameters of the metal lead itself in the wire bonding technology, and by selecting different wire bonding schemes, such as setting different combinations of the length and diameter of the first wire, the frequency domain response characteristics of high bandwidth and in-band gain flatness can be optimized for a specific type of photodiode and a specific circuit design of a transimpedance amplifier. Wherein, the optimal combination of the length and diameter of the first wire is determined based on the type of the photodiode and the circuit design of the transimpedance amplifier, which means that when the current combination of the length and diameter of the first wire matches the optimal combination of the length and diameter of the first wire, the bandwidth and the flatness of the in-band gain of the to-be-tested photoelectric converter are optimized. In this way, the system response curve associated with the current combination of the length and diameter of the first wire is adjusted to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire, so as to approach the target state from the starting state, i.e., the system response curve associated with the current combination of the length and diameter of the first wire.

[0041] In one possible implementation, the direction of adjustment of the total capacitance value of the capacitance array indicates the direction of adjustment of the current combination of the length and diameter of the first wire bonding with respect to the optimal combination of the length and diameter of the first wire bonding. Thus, based on the provision of the coarse adjustment manner by the combination of the length and diameter (corresponding to the width) of the first wire bonding, the fine adjustment manner is achieved by the capacitance array. The system response curve associated with the current combination of the length and diameter of the first wire bonding represents the starting state, and the system response curve associated with the optimal combination of the length and diameter of the first wire bonding represents the target state. The system bandwidth can be optimized by the inductive coupling of the first wire bonding, and the flatness of the in-band gain can be optimized by adjusting the total capacitance value of the capacitance array, so that the system response curve associated with the current combination of the length and diameter of the first wire bonding can be adjusted to approach the system response curve associated with the optimal combination of the length and diameter of the first wire bonding, i.e., the system response curve associated with the current combination of the length and diameter of the first wire bonding is adjusted to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire bonding. Therefore, the direction of adjustment of the total capacitance value of the capacitance array, such as increasing or decreasing the total capacitance value of the capacitance array, provides a reference for indicating the direction of adjustment of the current combination of the length and diameter of the first wire bonding with respect to the optimal combination of the length and diameter of the first wire bonding, which helps to select how to adjust the wire bonding scheme. Moreover, by using the adjustable capacitance or the switchable switch to selectively access the capacitance array, the total capacitance value of the capacitance array can be adjusted conveniently, which is more convenient than adjusting the combination of the length and diameter of the first wire bonding. Therefore, the direction of adjustment of the total capacitance value of the capacitance array can be used to determine how the current combination of the length and diameter of the first wire bonding should be adjusted, which is conducive to better adapting to the type of photodiode and the circuit design of the trans-impedance amplifier, and achieving the frequency domain response characteristics of high bandwidth and in-band gain flatness.

[0042] In one possible implementation, the welding manner of the first wire bonding is ball welding or wedge welding. Thus, the implementation means of the wire bonding can adopt ball bonding, wedge bonding, or other welding manners. Ball bonding generally adopts a hot pressure bonding method, i.e., the capillary wedge knife tip is heated to become spherical. Wedge bonding generally adopts an ultrasonic bonding method, i.e., ultrasonic waves are applied to the wedge-shaped wedge knife to achieve welding. Alternatively, the two welding manners can be combined, and a hot ultrasonic method is adopted by heating, pressing, and applying ultrasonic waves to the capillary wedge knife.

[0043] In a possible implementation, the total capacitance value of the capacitance array is adjusted to adjust the system response curve associated with the current combination of the length and diameter of the first wire, thereby improving the bandwidth and flatness of the in-band gain of the to-be-measured photoelectric converter. In this way, the combination of the length and diameter of the first wire is used to provide a coarse adjustment manner, the adjustability of the total capacitance value of the capacitance array is used to provide a fine adjustment manner, and the optimal combination of the length and diameter of the first wire is determined based on the type of the photodiode and the circuit design of the transimpedance amplifier, so that the type of the photodiode and the circuit design of the transimpedance amplifier are adapted, the system response curve is optimized, the frequency domain response characteristic of high bandwidth and flat in-band gain is achieved, the influence of the parasitic parameters on the measurement result is reduced, and the measurement accuracy is improved.

[0044] In a possible implementation, the optoelectronic S parameter of the to-be-measured photoelectric converter is an optoelectronic scattering parameter corresponding to the joint response of the photodiode and the transimpedance amplifier, the optoelectronic S parameter of the to-be-measured photoelectric converter before adjustment is used to determine the system response curve associated with the current combination of the length and diameter of the first wire before adjustment, and the optoelectronic S parameter of the to-be-measured photoelectric converter after adjustment is used to determine the system response curve associated with the current combination of the length and diameter of the first wire after adjustment. In this way, the optoelectronic S parameter of the to-be-measured photoelectric converter is measured by using the vector network analyzer and the optical signal generation module, and the measurement scheme of directly measuring the bandwidth and the gain and other parameters is provided, so that the loss of joint simulation and parasitic parameter extraction is saved; by using the optoelectronic S parameters before and after adjustment, the corresponding system response curve and the frequency domain response characteristic can be determined, which helps to improve the measurement accuracy.

[0045] In one possible embodiment, the adjustability of the total capacitance of the capacitor array, along with the adjustability of the current combination of the length and diameter of the first bonding wire, is used to provide adjustability of the bridge waveguide corresponding to the first bonding wire. The bridge waveguide adjustability is utilized to determine a bonding scheme that is compatible with the type of photodiode and the circuit design of the transimpedance amplifier. Alternatively, the bridge waveguide adjustability is utilized to perform mixed bonding scheme testing along with the circuit design of the transimpedance amplifier. Thus, to overcome the impact of external bonding wires and parasitic parameters of the preceding photodiode on the bandwidth of the transimpedance amplifier and the overall bandwidth of the photoelectric conversion device, the length and width (diameter) parameters of the metal wires can be set in wire bonding technology. By selecting different bonding schemes, such as different length and width (diameter) combinations, optimization can be achieved for a specific photodiode and a specific transimpedance amplifier, thereby achieving high bandwidth and frequency-domain gain-flatness within the bandwidth. Furthermore, for a specific transimpedance amplifier, mixed testing of different photodiode types and bonding schemes can be performed to select the optimal photodiode type and corresponding bonding scheme. In addition, when the transimpedance amplifier is not specific, the optimal transimpedance amplifier, the optimal photodiode and the corresponding optimal bonding solution can be selected based on the bandwidth and gain requirements of the application scenario.

[0046] Figure 2 Schematic diagram of a device for measuring photoelectric S parameters of a photoelectric converter provided in an embodiment of the present application. Figure 2As shown, the measurement apparatus 200 includes a vector network analyzer 201 and an optical signal generation module 210 for measuring the opto-electric S-parameters of a to-be-measured opto-electric converter 220. The vector network analyzer 201 is configured to generate an input voltage signal 290. The optical signal generation module 210 is configured to modulate an optical signal 292 provided by a light source 212 in the optical signal generation module 210 according to the input voltage signal 290, thereby obtaining a modulated optical signal 294. The to-be-measured opto-electric converter 220 receives the modulated optical signal 294 and provides an output voltage signal 296 corresponding to the modulated optical signal 294. The vector network analyzer 201 is further configured to compare the input voltage signal 290 and the output voltage signal 296, thereby obtaining the opto-electric S-parameters of the to-be-measured opto-electric converter 220. The to-be-measured opto-electric converter 220 includes a photodiode 222 and a trans-impedance amplifier 224. The photodiode 222 is configured to convert the modulated optical signal 294 into an input current signal 295, and the trans-impedance amplifier 224 is configured to convert the input current signal 295 into the output voltage signal 296. An anode 230 of the photodiode 222 is connected to an input end 236 of the trans-impedance amplifier 224 through a first wire 240. A cathode 232 of the photodiode 222 is configured to be connected to a power supply 235. Further, a capacitor array 250 including at least one capacitor is connected in parallel between the cathode 232 of the photodiode 222 and a ground end 238 of the trans-impedance amplifier 224. An optimal combination of a length and a diameter of the first wire 240 is determined based on a type of the photodiode 222 and a circuit design of the trans-impedance amplifier 224, and a total capacitance value of the capacitor array 250 is adjusted to adapt to a current combination of the length and the diameter of the first wire 240, thereby adjusting a system response curve associated with the current combination of the length and the diameter of the first wire 240 to approximate a system response curve associated with the optimal combination of the length and the diameter of the first wire 240.

[0047] Figure 2As shown in FIG. 2, the optical signal generating module 210 includes a driver 214 and a modulator 216. The light source 212 provides an optical signal 292, such as a stable optical signal 292 provided by a continuous wave (CW) laser, and the wavelength of the optical signal 292 is usually matched with the operating wavelength of the photoelectric converter 220 to be tested. The driver 214 is used to externally drive the modulator 216, so that the optical signal 292 provided by the light source 212 is modulated by the modulator 216 into an optical signal containing a radio frequency signal, so as to achieve modulation of the optical signal 292 provided by the light source 212 in the optical signal generating module 210 according to the input voltage signal 290, thereby obtaining a modulated optical signal 294. The modulator 216 can be a Mach-Zehnder modulator (MZM), for example. Generally, the operation principle of the Mach-Zehnder modulator is to divide the input optical signal into two equal signals, which enter two optical branches respectively, and an electro-optic material is used in the two optical branches, so that the refractive index changes with the size of the externally applied electrical signal (radio frequency signal). Thus, the change of the refractive index of the optical branch leads to the change of the signal phase, so that when the optical signals output by the two optical branches are combined together again, the combined optical signal will be an interference signal with varying intensity, which is equivalent to converting the change of the electrical signal into the change of the optical signal, thereby achieving modulation of the optical intensity. By using the Mach-Zehnder modulator or other suitable optical signal modulation methods, the change of the electrical signal can be loaded onto the optical signal, that is, the optical signal 292 provided by the light source 212 in the optical signal generating module 210 is modulated according to the input voltage signal 290, thereby obtaining the modulated optical signal 294. It should be understood that although the driver 214 and the modulator 216 are shown as separate components in FIG. 2, the driver 214 and the modulator 216 can be integrated into one component in other embodiments. Figure 2 As shown in FIG. 2, the power supply 235 is inside the photoelectric converter 220 to be tested, but in other embodiments, the power supply 235 can be outside the photoelectric converter 220 to be tested, or the power supply 235 can be provided separately, that is, not as part of the photoelectric converter 220 to be tested. In addition, the power supply 235 is used to provide the operating bias voltage of the photodiode 222, and therefore, any circuit or device having a biasing function can be used to replace the power supply 235, as long as the photodiode 222 can be operated in a suitable bias state so as to be used to convert the modulated optical signal 294 into the input current signal 295.

[0048] Referring to Figure 2 , Figure 2The measurement device 200 shown includes a vector network analyzer 201 and an optical signal generation module 210 for measuring the optoelectronic S parameters of the to-be-measured optoelectronic converter 220. As can be seen, the to-be-measured optoelectronic converter 220 can meet the requirements of low input impedance, low noise and wide frequency band characteristics as required by design, and the to-be-measured optoelectronic converter 220 can be applied in scenarios such as photodetectors, sensor interfaces, weak current signal amplification, etc., for example, in optical communication, medical equipment, particle detection, etc. Figure 2 The measurement device 200 shown utilizes the vector network analyzer 201 and the optical signal generation module 210 to facilitate the measurement of the optoelectronic S parameters of any to-be-measured optoelectronic converter 220, and by adjusting the system response curve associated with the current combination of the length and diameter of the first wire 240, it is beneficial to meet the characteristics of high bandwidth in the frequency domain and gain flatness within the bandwidth, effectively overcoming the influence of parasitic parameters such as parasitic capacitance on measurement accuracy, simplifying the measurement process while also improving measurement accuracy.

[0049] In summary, Figure 2 The measurement device 200 shown utilizes the vector network analyzer 201 and the optical signal generation module 210 to provide a measurement scheme for measuring the optoelectronic S parameters of the to-be-measured optoelectronic converter 220 and directly measuring parameters such as bandwidth and gain, saving the loss of joint simulation and parasitic parameter extraction; and taking into account the influence of the wire and parasitic parameters on the bandwidth of the transimpedance amplifier 224 and the overall bandwidth of the optoelectronic converter device, utilizing the combination of the length and diameter of the first wire 240 to provide a coarse adjustment method and utilizing the adjustability of the total capacitance value of the capacitor array 250 to provide a fine adjustment method, and based on the type of the photodiode 222 and the circuit design of the transimpedance amplifier 224 to determine the optimal combination of the length and diameter of the first wire 240, by adjusting the system response curve associated with the current combination of the length and diameter of the first wire 240 to approximate the system response curve associated with the optimal combination of the length and diameter of the first wire 240, the type of the photodiode 222 and the circuit design of the transimpedance amplifier 224 are adapted, the system response curve is optimized, the frequency domain response characteristics of high bandwidth and gain flatness within the bandwidth are achieved, the influence of parasitic parameters on the measurement result is reduced, and the measurement accuracy is improved.

[0050] Reference Figure 3In one possible implementation, the system response curve associated with the optimal combination of the length and diameter of the first wire 240 indicates that the bandwidth and flatness of the in-band gain of the under-test opto-electrical converter 220 are optimized when the current combination of the length and diameter of the first wire 240 in the under-test opto-electrical converter 220 matches the optimal combination of the length and diameter of the first wire 240. In this way, by selecting different wire bonding schemes, for example, by setting different combinations of the length and diameter of the first wire 240, the parameters of the length and width of the metal wire itself that can be set in the wire bonding technology can be used to optimize the high bandwidth and flat in-band gain frequency domain response characteristics for a specific type of photodiode 222 and a specific circuit design of the trans-impedance amplifier 224. Wherein the optimal combination of the length and diameter of the first wire 240 is determined based on the type of the photodiode 222 and the circuit design of the trans-impedance amplifier 224, which means that when the current combination of the length and diameter of the first wire 240 matches the optimal combination of the length and diameter of the first wire 240, it is reflected that the bandwidth and flatness of the in-band gain of the under-test opto-electrical converter 220 are optimized. In this way, the system response curve associated with the current combination of the length and diameter of the first wire 240 is realized from the starting state, that is, the system response curve associated with the current combination of the length and diameter of the first wire 240 is adjusted to approach the system response curve associated with the optimal combination of the length and diameter of the first wire 240.

[0051] In one possible implementation, the direction of adjustment of the total capacitance value of the capacitance array 250 indicates the direction of adjustment of the current combination of the length and diameter of the first bonding wire 240 relative to the optimal combination of the length and diameter of the first bonding wire 240. Thus, based on the combination of the length and diameter (corresponding to the width) of the first bonding wire 240 providing the coarse adjustment manner, the fine adjustment manner is achieved by the capacitance array 250. The system response curve associated with the current combination of the length and diameter of the first bonding wire 240 represents the starting state, and the system response curve associated with the optimal combination of the length and diameter of the first bonding wire 240 represents the target state. The inductive coupling of the first bonding wire 240 can optimize the system bandwidth, and the flatness of the gain within the bandwidth can be optimized by adjusting the total capacitance value of the capacitance array 250, so that the starting state can be approached towards the target state by adjusting the total capacitance value of the capacitance array 250, i.e. adjusting the system response curve associated with the current combination of the length and diameter of the first bonding wire 240 so as to approximate the system response curve associated with the optimal combination of the length and diameter of the first bonding wire 240. Therefore, the direction of adjustment of the total capacitance value of the capacitance array 250, such as increasing or decreasing the total capacitance value of the capacitance array 250, provides a reference for indicating the direction of adjustment of the current combination of the length and diameter of the first bonding wire 240 relative to the optimal combination of the length and diameter of the first bonding wire 240, which helps to select how to adjust the bonding wire scheme. Moreover, by using the adjustable capacitance or the switchable switch to selectively access the capacitance array 250, it is convenient to adjust the total capacitance value of the capacitance array 250, which is more convenient than adjusting the combination of the length and diameter of the first bonding wire 240. Therefore, the direction of adjustment of the total capacitance value of the capacitance array 250 can be used to determine how to adjust the current combination of the length and diameter of the first bonding wire 240, which is conducive to better adapting to the type of photodiode 222 and the circuit design of transimpedance amplifier 224, achieving the frequency domain response characteristics of high bandwidth and flat gain within the bandwidth.

[0052] In one possible embodiment, the adjustability of the total capacitance of the capacitor array 250, together with the adjustability of the current combination of the length and diameter of the first bonding wire 240, is used to provide adjustability of the bridge waveguide corresponding to the first bonding wire 240. The adjustability of the bridge waveguide is utilized to determine a bonding scheme that is compatible with the type of the photodiode 222 and the circuit design of the transimpedance amplifier 224. Alternatively, the adjustability of the bridge waveguide is utilized to perform mixed bonding scheme testing together with the circuit design of the transimpedance amplifier 224. In this way, to overcome the effects of parasitic parameters of external bonding wires and the preceding photodiode 222 on the bandwidth of the transimpedance amplifier 224 and the overall bandwidth of the photoelectric conversion device, the length and width (diameter) parameters of the metal wires can be set in wire bonding technology. By selecting different bonding schemes, such as different length and width (diameter) combinations, a frequency domain response characteristic with high bandwidth and gain flatness within the bandwidth can be optimized for a specific photodiode 222 and a specific transimpedance amplifier 224, thereby achieving high bandwidth and gain-flatness within the bandwidth. Furthermore, for a specific transimpedance amplifier 224, a mixed test of different photodiode 222 types and different bonding schemes can be performed to select the optimal photodiode 222 type and the corresponding optimal bonding scheme. Furthermore, when the transimpedance amplifier 224 is also unspecified, the optimal transimpedance amplifier 224, the optimal photodiode 222, and the corresponding optimal bonding scheme can be selected based on the bandwidth and gain requirements of the application scenario.

[0053] Figure 3 Schematic diagram of multiple wire bonding solutions provided in the embodiment of this application. Figure 3 As shown, there are three different types of photodiodes: photodiode type A310, photodiode type B312, and photodiode type C314. There are also three different transimpedance amplifier circuit designs: transimpedance amplifier circuit design A320, transimpedance amplifier circuit design B322, and transimpedance amplifier circuit design C324. Given the combinations of various photodiode types and transimpedance amplifier circuit designs, a bonding wire solution can be determined that optimizes the corresponding bandwidth and flatness, i.e., the optimal combination of the length and diameter of the corresponding first bonding wire can be determined. Figure 1As shown in the table, in the first row, corresponding to the type A 310 of photodiode, the circuit design A 320 of transimpedance amplifier, the circuit design B 322 of transimpedance amplifier, and the circuit design C 324 of transimpedance amplifier, the optimal wire bonding scheme corresponding to the bandwidth and flatness of each is: the length of the wire bonding is 200 microns, and the diameter is 20 microns; the length of the wire bonding is 300 microns, and the diameter is 25 microns; the length of the wire bonding is 400 microns, and the diameter is 30 microns. In the second row, corresponding to the type B 312 of photodiode, the circuit design A 320 of transimpedance amplifier, the circuit design B 322 of transimpedance amplifier, and the circuit design C 324 of transimpedance amplifier, the optimal wire bonding scheme corresponding to the bandwidth and flatness of each is: the length of the wire bonding is 200 microns, and the diameter is 20 microns; the length of the wire bonding is 300 microns, and the diameter is 20 microns; the length of the wire bonding is 400 microns, and the diameter is 30 microns. In the third row, corresponding to the type C 314 of photodiode, the circuit design A 320 of transimpedance amplifier, the circuit design B 322 of transimpedance amplifier, and the circuit design C 324 of transimpedance amplifier, the optimal wire bonding scheme corresponding to the bandwidth and flatness of each is: the length of the wire bonding is 200 microns, and the diameter is 20 microns; the length of the wire bonding is 200 microns, and the diameter is 20 microns; the length of the wire bonding is 400 microns, and the diameter is 25 microns. In this way, by selecting different wire bonding schemes, for example, setting different combinations of lengths and diameters of the first wire bonding, the high bandwidth and the flatness of the gain within the bandwidth of the frequency domain response characteristic can be achieved for a specific type of photodiode and a specific circuit design of the transimpedance amplifier. Wherein, the optimal combination of the length and the diameter of the first wire bonding is determined based on the type of the photodiode and the circuit design of the transimpedance amplifier, which means that when the current combination of the length and the diameter of the first wire bonding matches the optimal combination of the length and the diameter of the first wire bonding, it is reflected that the bandwidth and the flatness of the gain within the bandwidth of the photovoltaic converter to be tested are optimized. In this way, the system response curve associated with the current combination of the length and the diameter of the first wire bonding is moved closer to the target state, that is, the system response curve associated with the current combination of the length and the diameter of the first wire bonding is adjusted so as to approximate the system response curve associated with the optimal combination of the length and the diameter of the first wire bonding.

[0054] The method and the device provided by the embodiments of the present application are based on the same inventive concept. Since the principles of the method and the device for solving problems are similar, the embodiments, implementation manners, examples or implementation modes of the method and the device can be referred to each other, and the repeated parts will not be described herein. The embodiments of the present application further provide a system, which comprises a plurality of computing devices. The structure of each computing device can refer to the structure of the computing device described above. The functions or operations that can be implemented by the system can refer to the specific implementation steps in the above method embodiments and / or the specific functions described in the above device embodiments, which will not be described herein.

[0055] The embodiment of the present application further provides a computer readable storage medium, wherein computer instructions are stored in the computer readable storage medium, and when the computer instructions are run on a computer device (such as one or more processors), the computer instructions can implement the method steps in the above method embodiment. The specific implementation of the processor of the computer readable storage medium in executing the above method steps can refer to the specific operations described in the above method embodiment and / or the specific functions described in the above device embodiment, and will not be described here again.

[0056] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system or a computer program product. The present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. The embodiments of the present application can be realized, wholly or partially, by software, hardware, firmware or any combination thereof. When realized by software, the above embodiments can be realized, wholly or partially, in the form of a computer program product. The present application can take the form of a computer program product implemented on one or more computer-usable storage media having computer-usable program code embodied therein. The computer program product includes one or more computer instructions. When the computer program instructions are loaded or executed on a computer, the above-mentioned processes or functions are wholly or partially generated according to the embodiments of the present application. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable devices. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be transferred from one website, computer, server or data center to another website, computer, server or data center through a wired (such as coaxial cable, optical fiber, digital subscriber line) or wireless (such as infrared, wireless, microwave, etc.) manner. The computer readable storage medium can be any available medium accessible by a computer or a data storage device such as a server, data center and the like containing a set of one or more available media. The available media can be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium or a semiconductor medium. The semiconductor medium can be a solid state disk or a random access memory, a flash memory, a read-only memory, an electrically erasable programmable read-only memory, a register or any other suitable storage medium.

[0057] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart or flowsheet block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks ​ one or more flowcharts and / or blocks

[0058] In the above embodiments, the description of each embodiment is focused on respectively, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments. Obviously, those skilled in the art can make various modifications and variations to the embodiments of the present application without departing from the spirit and scope of the embodiments of the present application. The steps in the method of the embodiments of the present application can be adjusted, combined or deleted according to actual needs; the modules in the system of the embodiments of the present application can be divided, combined or deleted according to actual needs. If these modifications and variations of the embodiments of the present application belong to the scope of the claims of the present application and the equivalent technologies thereof, the present application also intends to include these modifications and variations.

Claims

1. A method for measuring the opto-electric S-parameters of an opto-electric converter, characterized in that, The measurement method comprises: generating, by a vector network analyzer, an input voltage signal, and modulating, by an optical signal generation module, an optical signal provided by a light source in the optical signal generation module according to the input voltage signal, so as to obtain a modulated optical signal; receiving, by a to-be-measured photoelectric converter, the modulated optical signal and providing an output voltage signal corresponding to the modulated optical signal; and comparing, by the vector network analyzer, the input voltage signal and the output voltage signal, so as to obtain a photoelectric S parameter of the to-be-measured photoelectric converter, wherein the to-be-measured photoelectric converter comprises a photodiode and a trans-impedance amplifier, the photodiode is configured to convert the modulated optical signal into an input current signal, the trans-impedance amplifier is configured to convert the input current signal into the output voltage signal, an anode of the photodiode is connected to an input end of the trans-impedance amplifier through a first wire, a cathode of the photodiode is configured to be connected to a power supply, and a capacitor array comprising at least one capacitor is connected in parallel between the cathode of the photodiode and a ground end of the trans-impedance amplifier, an optimal combination of a length and a diameter of the first wire is determined based on a type of the photodiode and a circuit design of the trans-impedance amplifier, a total capacitance value of the capacitor array is adjusted to adapt to a current combination of the length and the diameter of the first wire, so as to adjust a system response curve associated with the current combination of the length and the diameter of the first wire to approximate a system response curve associated with the optimal combination of the length and the diameter of the first wire.

2. The measurement method according to claim 1, characterized in that, The first wire is configured to provide a signal transmission path between the photodiode and the trans-impedance amplifier, and the capacitor array is configured to provide a ground coupling path parallel to the signal transmission path.

3. The measurement method according to claim 2, characterized in that, An inductive coupling of the first wire is configured to optimize a bandwidth of the to-be-measured photoelectric converter, and the capacitor array is configured to optimize a flatness of a gain within the bandwidth of the to-be-measured photoelectric converter.

4. The measurement method according to claim 1, characterized by, The capacitor array comprises an adjustable capacitor, and a total capacitance value of the adjustable capacitor is adjusted to adjust the total capacitance value of the capacitor array.

5. The method of claim 1, wherein, The at least one capacitor is selectively accessed to the capacitor array through a switchable switch to adjust the total capacitance value of the capacitor array.

6. The measurement method according to claim 1, characterized by, The system response curve associated with the optimal combination of the length and the diameter of the first wire indicates that, when the current combination of the length and the diameter of the first wire in the to-be-measured photoelectric converter adopts the optimal combination of the length and the diameter of the first wire, the bandwidth and the flatness of the gain within the bandwidth of the to-be-measured photoelectric converter are optimized.

7. The measurement method according to claim 1, characterized by, An adjustment direction of the total capacitance value of the capacitor array indicates an adjustment direction of the current combination of the length and the diameter of the first wire relative to the optimal combination of the length and the diameter of the first wire.

8. The measurement method of claim 1, wherein, A welding mode of the first wire is ball welding or wedge welding.

9. The method of claim 1, wherein, The total capacitance value of the capacitor array is adjusted to adjust the system response curve associated with the current combination of the length and the diameter of the first wire, so as to improve the bandwidth and the flatness of the gain within the bandwidth of the to-be-measured photoelectric converter.

10. The method of claim 1, wherein, The opto-electric S-parameter of the to-be-tested opto-electric converter is an opto-electric scattering parameter corresponding to a joint response including the photodiode and the trans-impedance amplifier, the opto-electric S-parameter of the to-be-tested opto-electric converter before adjustment is used to determine a system response curve associated with the current combination of the length and diameter of the first wire before adjustment, and the opto-electric S-parameter of the to-be-tested opto-electric converter after adjustment is used to determine a system response curve associated with the current combination of the length and diameter of the first wire after adjustment.

11. The measurement method of claim 1, wherein, The adjustability of the total capacitance value of the capacitance array is used together with the adjustability of the current combination of the length and diameter of the first wire to provide the adjustability of the bridge waveguide corresponding to the first wire, and the adjustability of the bridge waveguide is utilized to determine a wire scheme adapted to the type of the photodiode and the circuit design of the trans-impedance amplifier, or the adjustability of the bridge waveguide is utilized to conduct a wire scheme mixed test together with the circuit design of the trans-impedance amplifier.

12. A measuring device for opto-electric S-parameters of an opto-electric converter, characterized by The measurement device comprises: a vector network analyzer for generating an input voltage signal; and an optical signal generation module for modulating an optical signal provided by a light source in the optical signal generation module according to the input voltage signal to obtain a modulated optical signal, wherein the to-be-tested opto-electric converter receives the modulated optical signal and provides an output voltage signal corresponding to the modulated optical signal, The vector network analyzer is further configured to compare the input voltage signal and the output voltage signal to obtain an opto-electric S-parameter of the to-be-tested opto-electric converter, The to-be-tested opto-electric converter comprises a photodiode and a trans-impedance amplifier, the photodiode is configured to convert the modulated optical signal into an input current signal, and the trans-impedance amplifier is configured to convert the input current signal into the output voltage signal, an anode of the photodiode is connected to an input end of the trans-impedance amplifier through a first wire, a cathode of the photodiode is configured to be connected to a power supply, and a capacitance array including at least one capacitor is connected in parallel between the cathode of the photodiode and a ground end of the trans-impedance amplifier, an optimal combination of the length and diameter of the first wire is determined based on the type of the photodiode and the circuit design of the trans-impedance amplifier, and a total capacitance value of the capacitance array is adjusted to adapt to the current combination of the length and diameter of the first wire, so as to adjust a system response curve associated with the current combination of the length and diameter of the first wire to approximate a system response curve associated with the optimal combination of the length and diameter of the first wire.

13. The measuring device of claim 12, wherein, The system response curve associated with the optimal combination of the length and diameter of the first wire indicates that the bandwidth and the flatness of the in-band gain of the to-be-tested opto-electric converter are optimized when the current combination of the length and diameter of the first wire in the to-be-tested opto-electric converter adopts the optimal combination of the length and diameter of the first wire.

14. The measuring device of claim 12, wherein, The adjustment direction of the total capacitance value of the capacitance array indicates the adjustment direction of the current combination of the length and diameter of the first wire relative to the optimal combination of the length and diameter of the first wire.

15. The measuring device of claim 12, wherein, The adjustability of the total capacitance value of the capacitance array is used together with the adjustability of the current combination of length and diameter of the first wire to provide adjustability of a bridge waveguide corresponding to the first wire, the adjustability of the bridge waveguide being utilized to determine a wire scheme that is adapted to the type of the photodiode and the circuit design of the transimpedance amplifier, or the adjustability of the bridge waveguide is utilized to conduct a wire scheme mixed test together with the circuit design of the transimpedance amplifier.

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