A comprehensive testing device and method for microwave chip wafer-level performance.

Abstract

This invention discloses a comprehensive microwave chip wafer-level performance testing device and method, belonging to the field of microwave chip testing technology. The device includes a signal source, receiver, coupler, circulator, switch, matching unit, chuck, etc., forming a specialized comprehensive microwave chip wafer-level performance testing system. The testing method includes comprehensive measurements of scattering parameters and derived coefficients, distortion parameters, power parameters, spectral parameters, pulse parameters, noise parameters, and nonlinear parameters. This invention effectively improves testing accuracy and speed, thus solving the challenge of high-precision and high-efficiency testing of microwave chips. A single testing device can fully evaluate testing capabilities, significantly reducing construction costs.

Description

Technical Field

[0001] This invention belongs to the field of microwave chip testing technology, specifically relating to a comprehensive microwave chip wafer-level performance testing device and method. Background Technology

[0002] Testing microwave chips, including microwave amplifiers, low-noise amplifiers, differential amplifiers, switches, mixers, T / R monolithic chips, MMICs, and heterogeneous chips, is a crucial part of the microwave integrated circuit industry. Test data is needed for design iteration during chip design, for process control and good product sorting during production, and for secondary development and design of circuits during chip application.

[0003] Existing chip wafer-level testing methods and systems mainly use general-purpose instruments and equipment, such as vector network parameter analyzers, signal generators, spectrum analyzers, power meters, probe stations, probes, and calibration wafers. The disadvantages can be summarized in two points.

[0004] First, the system composed of general-purpose instruments and equipment is not designed for wafer-level testing scenarios and has not been systematically optimized for chip wafer testing. Testing multiple parameters of a chip often requires switching between multiple instruments and equipment and multiple systems. The testing functions of a single test or a single set of equipment are limited, so it is difficult to further improve the testing accuracy and testing efficiency.

[0005] Secondly, systems composed of general-purpose instruments and equipment lack systematic functional specifications, only providing functional specifications for individual instruments and probe stations. Furthermore, they typically require combinations from multiple countries, companies, and models, resulting in limited compatibility. Therefore, before system construction, a professional and lengthy construction assessment is needed, leading to high costs associated with system failures and wasted resources. During system construction, the need for general-purpose instruments and equipment results in high hardware and software costs. After system implementation, due to procurement from multiple companies, it is difficult to accurately locate faulty instruments and equipment when system problems occur, leading to high after-sales maintenance costs. Summary of the Invention

[0006] To address the aforementioned problems in the existing technology, this invention proposes a comprehensive microwave chip wafer-level performance testing device and method. The device and method are rationally designed, overcome the shortcomings of the existing technology, and have good performance.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A comprehensive microwave chip wafer-level performance testing device includes: One time base signal unit is used to provide the system's standard frequency reference; One local oscillator unit is used to generate and provide local oscillator signals to all receivers; M+1 signal source units, including M signal sources for connecting the test ports of the device under test (DUT) and one additional signal source, are used to generate M+1 microwave test signals. M circulators, each circulator connected in series after M signal source units, the circulators include a first type of circulator and a second type of circulator, the third port of the first type of circulator is connected to a high-sensitivity receiver, and the third port of the second type of circulator is connected to a high-power matched load. M couplers, each connected after a circulator, with its main output connected to a matching unit to connect to the DUT. Its forward coupling port and reverse coupling port are used to extract the forward incident signal and the reverse reflected / transmitted signal, respectively. 2M conventional receivers are used to receive the forward and reverse signals from the M channels extracted by the M couplers and perform down-conversion processing; N high-sensitivity receivers are used to receive and process ultra-low power signals; MN high-power matching loads are used to absorb signals transmitted toward the signal source; A gating switch, the moving end of which is connected to the output of source 0, and the two stationary ends of which are respectively connected to the test channels corresponding to two different type 1 circulators, is used to selectively inject the signal of source 0 into one of the two test channels; A wafer chuck unit is used to carry and hold the DUT; A four-dimensional motion unit is used to drive the wafer chuck unit to move in the X, Y, and Z translational directions and the θ rotational direction to adjust the DUT's attitude and contact position; M matching units are used to convert the microwave signal of the system into the coplanar waveguide signal input to the DUT; A standard component with pre-calibrated open circuit, short circuit, load, pass, and transmission states for system error calibration; An intermediate frequency (IF) processing sampling unit with 2M+N input channels is used for IF conditioning and analog-to-digital conversion of signals from all conventional and high-sensitivity receivers.

[0008] Furthermore, it also includes: a CPU control unit, used to control the opening and closing and switching of the signal source unit, the four-dimensional motion unit, the voltage source, and the switch, and to perform error compensation and parameter calculation on the sampled data based on the calibration data of the standard component; The power supply unit is used to power the entire device; Voltage source unit, used to provide additional voltage and logic control signals to DUT.

[0009] Furthermore, the local oscillator signal output by the local oscillator signal unit is power-divided to the 2M conventional receivers and the N high-sensitivity receivers; The N high-sensitivity receivers are equipped with switches and matching loads, which direct the signal to the load when not in operation; The standard component can be used to calibrate the signal power at the DUT contact point, calculate and compensate for microwave interference signals in the system, and correct the phase reference plane to the chip input position or half the through line length.

[0010] Furthermore, the motion speed and displacement accuracy of the four-dimensional motion unit are configured such that its motion speed matches the DUT electrical coupling stabilization time and the system electrical scanning speed, and the maximum cumulative value of its displacement error is not greater than the size of the DUT contact point.

[0011] Furthermore, when M=4, the signal source unit includes a first signal source, a second signal source, a third signal source, and a fourth signal source, corresponding to the first to fourth couplers respectively; the number of the first type of circulator is 2, corresponding to the first signal source and the fourth signal source respectively; the number of the second type of circulator is 2, corresponding to the second signal source and the third signal source respectively; the two static terminals of the gating switch are respectively connected to the test channels corresponding to the first signal source and the fourth signal source; the number of high-sensitivity receivers is 2, with the first and second high-sensitivity receivers respectively connected to the third port of the first type of circulator; the number of conventional receivers is 8, with the first coupler corresponding to the first and second conventional receivers, the second coupler corresponding to the third and fourth conventional receivers, the third coupler corresponding to the fifth and sixth conventional receivers, and the fourth coupler corresponding to the seventh and eighth conventional receivers.

[0012] A comprehensive microwave chip wafer-level performance testing method, employing a microwave chip wafer-level performance testing device as described above, wherein M=4 in the device, the method includes the following steps: S1: The CPU control unit moves the wafer chuck through the four-dimensional motion unit, so that the input and output ports of the DUT are connected to the first matching unit and the fourth matching unit respectively; S2: Apply bias voltage to the DUT through the voltage source unit; S3: Turn on the first signal source, and the signal is loaded to the input port of the DUT through the first circulator, the first coupler, and the first matching unit; When the signal passes through the first coupler, part of the signal is coupled out and enters the first conventional receiver; The reflected signal from the DUT enters the first high-sensitivity receiver after passing through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The DUT's transmitted signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth coupler. When passing through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver. S4: Turn on the fourth signal source. The signal is applied to the input port of the DUT through the fourth circulator, the fourth coupler, and the fourth matching unit. When the signal passes through the fourth coupler, part of the signal is coupled out and enters the seventh conventional receiver; The reflected signal from the DUT enters the second high-sensitivity receiver after passing through the fourth matching unit, the fourth coupler, and the fourth circulator. When passing through the fourth coupler, part of the reverse signal is coupled out and enters the eighth conventional receiver. The reverse leakage signal of the DUT enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. S5: All receivers send the down-converted intermediate frequency signal to the intermediate frequency processing sampling unit for sampling. The CPU control unit performs vector error correction on the sampling data of all receivers in S2 and S4 based on the pre-stored calibration data. S6: Based on the corrected data, calculate the scattering parameters, derived coefficients, distortion parameters, and power parameters of the DUT; S7: Control the signal source to output a pulse signal, set the pulse width, duty cycle, frequency and power, repeat steps S1-S5, and obtain the power parameters and pulse parameters of the DUT through the corrected data; S8: Control the local oscillator signal scanning of the receiver so that the center frequency and source frequency of the receiver can be controlled separately. The intermediate frequency processing unit sets the intermediate frequency bandwidth. Repeat steps S1-S6 to obtain the spectrum parameters, nonlinear parameters and noise parameters of the DUT. S9: After repeating steps S1-S4, simultaneously turn on the first and fourth signal sources, load signals bidirectionally, and the first, second, seventh, and eighth conventional receivers work simultaneously; at this time, an artificial equivalent output standing wave is formed at the DUT output end. Adjust the phase and amplitude of the fourth signal source to scan the DUT output standing wave and obtain the power parameters of the DUT. S10: Turn off the first signal source, and the first and second conventional receivers and the second high-sensitivity receiver operate. Change the reference impedance of the first matching unit, and the second high-sensitivity receiver scans the noise gain that changes due to the system output impedance to obtain the noise parameters of the DUT. S11: Simultaneously turn on the first signal source and the auxiliary signal source, and switch the gating switch to combine the first signal source and the auxiliary signal source. At this time, it is equivalent to using a two-tone signal to excite the DUT. The signal is loaded to the input port of the DUT through the first circulator, the first coupler, and the first matching unit. When the signal passes through the first coupler, some of it is coupled out and enters the first conventional receiver; The reflected signal from the DUT enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When it passes through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The DUT's transmitted signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator. When passing through the fourth coupler, some of the signal is coupled out and enters the eighth conventional receiver. S12: Simultaneously turn on the fourth signal source and the auxiliary signal source, and switch the gating switch to combine the fourth signal source and the auxiliary signal source. At this time, it is equivalent to using a two-tone signal to excite the DUT in reverse. The signal is loaded to the output port of the DUT through the fourth circulator, the fourth coupler, and the fourth matching unit. When passing through the fourth coupler, some of the signal is coupled out and enters the seventh conventional receiver; The DUT reflected signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator. When it passes through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver. The reverse leakage signal of the DUT enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The parameters that can be tested at this time include distortion parameters and nonlinear parameters; S13: Turn on the first signal source and the second signal source. If the device under test is a mixer, connect the second signal source to the intermediate frequency port of the mixer. The second signal source serves as the intermediate frequency signal. The signal from the first signal source is loaded onto the input port of the DUT through the first circulator, the first coupler, and the first matching unit; when passing through the first coupler, part of the signal is coupled out and enters the first conventional receiver; the DUT reflected signal passes through the first matching unit, the first coupler, and the first circulator and enters the first high-sensitivity receiver; when passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The intermediate frequency (IF) signal is loaded onto the input port of the DUT through the second circulator, the second coupler, and the second matching unit; when passing through the second coupler, part of the signal is coupled out and enters the third conventional receiver; the reflected signal of the IF signal passes through the second matching unit and the second coupler, and when passing through the second coupler, part of the signal is coupled out and enters the fourth conventional receiver. The DUT's transmitted signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator. When passing through the fourth coupler, some of the signal is coupled out and enters the eighth conventional receiver. S14: The second signal source and the fourth signal source are turned on, and the second signal source is kept connected to the intermediate frequency port of the mixer as an intermediate frequency signal; The intermediate frequency (IF) signal is loaded onto the input port of the DUT through the second circulator, the second coupler, and the second matching unit; when passing through the second coupler, part of the signal is coupled out and enters the third receiver; the reflected signal of the IF signal passes through the second matching unit and the second coupler, and when passing through the second coupler, part of the signal is coupled out and enters the fourth conventional receiver. The reverse test signal of the DUT is loaded to the input port of the DUT through the fourth circulator, the fourth coupler, and the fourth matching unit; when passing through the fourth coupler, part of the signal is coupled out and enters the seventh conventional receiver; the DUT reflected signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator; when passing through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver. The reverse transmission signal enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The parameters that can be tested at this time include nonlinear parameters, scattering parameters and derived coefficients, and spectral parameters; S15: The first, second, third, and fourth signal sources are turned on in turn, and the conventional receiver turns on scanning. If the device under test is a differential device, the first and second signal sources are turned on simultaneously, and the third and fourth signal sources are turned on simultaneously. At this time, the parameters that can be tested are the scattering parameters and the derived coefficients.

[0013] The beneficial technical effects of this invention are as follows: (1) A single test can achieve comprehensive measurement of scattering parameters and derived coefficients, distortion parameters, power parameters, spectrum parameters, pulse parameters, noise parameters and nonlinear parameters, and effectively improve test accuracy and test speed, thus solving the problem of high-precision and high-efficiency testing of microwave chips.

[0014] (2) For specialized scenarios, the system integrates vector network analyzer, power meter, signal generator, spectrum analyzer, and probe station, while eliminating unnecessary functions of general-purpose instruments, thus significantly reducing hardware costs. A single test setup can fully evaluate testing capabilities, providing system indicators and comparisons with the requirements of the same chip DUT, greatly reducing construction costs. Furthermore, the modular design of this invention significantly improves maintainability and greatly reduces equipment maintenance costs. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a microwave chip wafer-level performance comprehensive testing device according to the present invention; Figure 2 This is a schematic diagram showing the connection between the DUT and the first and fourth matching units in this invention; Figure 3This is a schematic diagram showing the connection between the DUT and the first, second, and fourth matching units in this invention; Figure 4 This is a schematic diagram showing the connection between the DUT and the first to fourth matching units in this invention; Detailed Implementation

[0016] The specific embodiments of the present invention will be further described below with reference to specific examples: A comprehensive performance testing device for microwave chips at the wafer level, such as Figure 1 As shown, it includes 1 time base signal unit, 1 local oscillator signal unit, M+1 signal source units, M circulators, M couplers, 2M conventional receivers, N high-sensitivity receivers, MN high-power matching loads, 1 wafer chuck unit, a four-dimensional motion unit, M matching units, 1 standard component, 1 intermediate frequency processing sampling unit, 1 CPU control unit, 1 power supply unit, K voltage source units, and several switches, conventional loads, cables, and filter units; The time base signal unit is used to provide the standard frequency reference for the system, which directly determines the frequency accuracy of the system. The local oscillator signal unit is used to generate and provide local oscillator signals to all receivers. The output local oscillator signal is power-divided to the 2M conventional receivers and the N high-sensitivity receivers. The common local oscillator of all receivers is a requirement of the test method and an important hardware foundation of the system. The signal source unit includes M signal sources for connecting to the test ports of the device under test (DUT) and one additional signal source. It generates M+1 microwave test signals and has requirements for maximum and minimum signal power, harmonic suppression, signal control linearity, and modulation signal generation. Its signal quality also limits the capabilities of the test system. Its capabilities cannot approach an ideal state and are related to the hardware engineering implementation capabilities. A circulator, with each circulator connected in series after M signal source units, is used to control the direction of signal flow. At low power, other devices such as bridges can be used instead, but at high power, circulators have certain advantages in terms of power protection of the source. Circulators include first-type circulators and second-type circulators. The third port of the first-type circulator is connected to a high-sensitivity receiver, and the third port of the second-type circulator is connected to a high-power matching load. Couplers, each connected after a circulator, have their main output connected to a matching unit to connect to the DUT. Their forward coupling port and reverse coupling port are used to extract the forward incident signal and the reverse reflected / transmitted signal, respectively. The goal is to minimize signal coupling to the wrong port, i.e., to improve the directivity of the device. A conventional receiver is used to receive the forward and reverse signals from M channels extracted by the M couplers. The frequency is reduced to an intermediate frequency (IF) via a local oscillator. It includes filtering units and sends the 2M signals to the IF processing and sampling unit. Receiver sensitivity, linearity, and compression point will affect system performance. The design of the 2M conventional receivers focuses on the linearity range, while ensuring a superior compression point is necessary to meet the testing requirements of high-power chips. A high-sensitivity receiver is used to receive and process ultra-low power signals. Prioritizing increased sensitivity enhances the ability to test extremely small signals, compensating for the insufficient sensitivity of conventional receivers in noise testing or testing of very small chips. Internally equipped with a switch and matching load, it directs the signal to the load when not in operation. High-sensitivity receivers can receive smaller signals (below -135dBm) than conventional receivers, but their ability to receive large signals is weak. Conventional receivers can receive larger signals (typically +0dBm), but their ability to receive small signals is weak (typically around -120dBm). A high-power matching load is used to absorb signals transmitted toward the signal source. If the matching absorption is not good, the signal will bounce repeatedly in the path, introducing more and larger test errors. A selector switch, whose moving end is connected to the output end of source 0, and whose two stationary ends are respectively connected to the test channels corresponding to two different first-type circulators, is used to selectively inject the signal of source 0 into one of the two test channels; The wafer chuck unit is mainly used to hold and fix the die under test (DUT), such as wafer, chip, or bare die. The four-dimensional motion unit is used to drive the wafer chuck unit to move in the X, Y, and Z translational directions and the θ rotational direction to adjust the DUT's attitude and contact position, so that the contact points between the matching unit and the DUT are physically connected repeatedly. Its motion speed is matched with the DUT's electrical coupling stabilization time and the system's electrical scanning speed, and its maximum cumulative displacement error is not greater than the size of the DUT's contact point. Engineering implementation requires a certain balance between speed, accuracy, and cost; higher performance is not always better. M matching units are used to convert the coaxial, rectangular waveguide, and other microwave signals output by the system into coplanar waveguide signals input to the DUT, so as to achieve physical and electrical matching between the system and the DUT. Microwave probes, microwave probe cards, and other hardware are commonly used matching units. The standard component has pre-calibrated open circuit, short circuit, load, through, and transmission states for system error calibration. Using the standard open and short circuit, the high-sensitivity receiver and conventional receiver of this channel are used to correct the output power of the signal. The signal power at the DUT contact point is directly calibrated, and the microwave interference signal flowing between the units of the invention device is calibrated and compensated according to the combination of different states. The reference plane for the signal phase is calculated and corrected to the chip input position or half the through line length. The intermediate frequency (IF) processing sampling unit has 2M+N input channels, which are used to perform IF conditioning and analog-to-digital conversion on signals from all conventional and high-sensitivity receivers, converting microwave IF signals into digital signals.

[0017] It also includes: a CPU control unit, used to control the switching of the signal source unit and the external amplitude stabilizer, the four-dimensional motion unit, the voltage source, the opening and closing of the switch, and to perform error compensation and calculation of parameters such as gain, reflection coefficient, intermodulation, output power, pulse width, and noise figure on the sampled data based on the calibration data of the standard component; The power supply unit is used to power the entire device; The voltage source unit is used to provide additional voltage and logic control signals to the DUT. The voltage can be used to supply voltage to the chip, and the logic control signals control the internal state of the chip.

[0018] When M=4, the signal source unit includes a first signal source, a second signal source, a third signal source, and a fourth signal source, corresponding to the first to fourth couplers respectively; there are two first-type circulators, corresponding to the first and fourth signal sources respectively; there are two second-type circulators, corresponding to the second and third signal sources respectively; the two static terminals of the gating switch are connected to the test channels corresponding to the first and fourth signal sources respectively; there are two high-sensitivity receivers, with the first and second high-sensitivity receivers connected to the third port of the first-type circulator respectively; there are eight conventional receivers, with the first coupler corresponding to the first and second conventional receivers, the second coupler corresponding to the third and fourth conventional receivers, the third coupler corresponding to the fifth and sixth conventional receivers, and the fourth coupler corresponding to the seventh and eighth conventional receivers.

[0019] A comprehensive microwave chip wafer-level performance testing method, employing a microwave chip wafer-level performance testing device as described above, wherein M=4 in the device, includes the following steps: S1: The CPU control unit moves the wafer chuck through the four-dimensional motion unit, so that the input and output ports of the DUT are connected to the first matching unit and the fourth matching unit respectively; S2: The CPU control unit controls the voltage source unit to apply a bias voltage to the DUT through the power supply unit, and at the same time tests the current used by the chip. S3: Turn on the first signal source. The signal is applied to the input port of the DUT through the first circulator, the first coupler, and the first matching unit, such as... Figure 2 As shown; When the signal passes through the first coupler, part of the signal is coupled out and enters the first conventional receiver; The reflected signal from the DUT enters the first high-sensitivity receiver after passing through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The DUT's transmitted signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth coupler. When passing through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver. S4: Turn on the fourth signal source. The signal is applied to the input port of the DUT through the fourth circulator, the fourth coupler, and the fourth matching unit. When the signal passes through the fourth coupler, part of the signal is coupled out and enters the seventh conventional receiver; The reflected signal from the DUT enters the second high-sensitivity receiver after passing through the fourth matching unit, the fourth coupler, and the fourth circulator. When passing through the fourth coupler, part of the reverse signal is coupled out and enters the eighth conventional receiver. The reverse leakage signal of the DUT enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. S5: All receivers send the down-converted intermediate frequency signal to the intermediate frequency processing sampling unit for sampling. The CPU control unit performs vector error correction on the sampling data of all receivers in S2 and S4 based on the pre-stored calibration data. The correction method can be selected according to the frequency band, the characteristics of the device under test, and the focus, such as SOLT, enhanced response, TRL, LRRM, etc. S6: Based on the corrected data, calculate the scattering parameters, derived coefficients, distortion parameters, and power parameters of the DUT, as shown in Table 1; Table 1 ; S7: Control the signal source to output a pulse signal, set the pulse width, duty cycle, frequency and power, repeat steps S1-S5, and obtain the power parameters and pulse parameters of the DUT through the corrected data, as shown in Table 2; Table 2 ; S8: Control the local oscillator signal scanning of the receiver so that the center frequency and source frequency of the receiver can be controlled separately. The intermediate frequency processing unit sets the intermediate frequency bandwidth. Repeat steps S1-S6 to obtain the spectrum parameters, nonlinear parameters and noise parameters of the DUT, as shown in Table 3. Table 3 ; S9: After repeating steps S1-S4, simultaneously turn on the first and fourth signal sources, and load signals in both directions at the same time. The first, second, seventh and eighth conventional receivers work simultaneously. At this time, an artificial equivalent output standing wave is formed at the DUT output. Adjust the phase and amplitude of the fourth signal source to achieve scanning of the DUT output standing wave. This is equivalent to the load traction test of a conventional system, and the power parameters of the DUT are obtained, as shown in Table 4. Table 4 ; S10: Turn off the first signal source, and the first and second conventional receivers and the second high-sensitivity receiver work to change the reference impedance of the first matching unit. The second high-sensitivity receiver scans the noise gain that changes due to the system output impedance and obtains the noise parameters of the DUT, as shown in Table 5. At this time, the hardware implementation requirement of the first matching unit is not just a "conventional probe", but a "probe with a cascaded impedance change chip". Table 5 ; S11: Simultaneously turn on the first signal source and the auxiliary signal source, and switch the gating switch to combine the first signal source and the auxiliary signal source. At this time, it is equivalent to using a two-tone signal to excite the DUT. The signal is loaded to the input port of the DUT through the first circulator, the first coupler, and the first matching unit. When the signal passes through the first coupler, some of it is coupled out and enters the first conventional receiver; The reflected signal from the DUT enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When it passes through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The DUT's transmitted signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator. When passing through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver (after entering the receiver, it will be received immediately, and the amplitude and phase will be calculated as the initial data). S12: Simultaneously turn on the fourth signal source and the auxiliary signal source, and switch the gating switch to combine the fourth signal source and the auxiliary signal source. At this time, it is equivalent to using a two-tone signal to excite the DUT in reverse. The signal is loaded to the output port of the DUT through the fourth circulator, the fourth coupler, and the fourth matching unit. When passing through the fourth coupler, some of the signal is coupled out and enters the seventh conventional receiver; The DUT reflected signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator. When it passes through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver. The reverse leakage signal of the DUT enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The parameters that can be tested at this time include distortion parameters and nonlinear parameters, as shown in Table 6; Table 6 ; S13: Turn on the first signal source and the second signal source. If the device under test is a mixer, connect the second signal source to the intermediate frequency port of the mixer. The second signal source serves as the intermediate frequency signal. The signal from the first signal source is applied to the input port of the DUT through the first circulator, the first coupler, and the first matching unit, such as... Figure 3 As shown; when passing through the first coupler, part of the signal is coupled out and enters the first conventional receiver; the DUT reflected signal enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator; when passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The intermediate frequency (IF) signal is loaded onto the input port of the DUT through the second circulator, the second coupler, and the second matching unit; when passing through the second coupler, part of the signal is coupled out and enters the third conventional receiver; the reflected signal of the IF signal passes through the second matching unit and the second coupler, and when passing through the second coupler, part of the signal is coupled out and enters the fourth conventional receiver. The DUT's transmitted signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator. When passing through the fourth coupler, some of the signal is coupled out and enters the eighth conventional receiver. S14: The second signal source and the fourth signal source are turned on, and the second signal source is kept connected to the intermediate frequency port of the mixer as an intermediate frequency signal; The intermediate frequency (IF) signal is loaded onto the input port of the DUT through the second circulator, the second coupler, and the second matching unit; when passing through the second coupler, part of the signal is coupled out and enters the third receiver; the reflected signal of the IF signal passes through the second matching unit and the second coupler, and when passing through the second coupler, part of the signal is coupled out and enters the fourth conventional receiver. The reverse test signal of the DUT is loaded to the input port of the DUT through the fourth circulator, the fourth coupler, and the fourth matching unit; when passing through the fourth coupler, part of the signal is coupled out and enters the seventh conventional receiver; the DUT reflected signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator; when passing through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver. The reverse transmission signal enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The parameters that can be tested at this time include nonlinear parameters, scattering parameters and derived coefficients, and spectral parameters, as shown in Table 7. Table 7 ; S15: The first, second, third, and fourth signal sources are turned on alternately; all signals are turned on for scanning in a conventional receiver. If the device under test is a differential device, the first and second signal sources are turned on simultaneously, and the third and fourth signal sources are turned on simultaneously. Figure 4 As shown in Table 8, the parameters that can be tested at this time are the scattering parameters and the derived coefficients. Table 8 ; At this point, a key performance indicator (KPI) system for evaluating the testing capabilities of this testing device can be established. This KPI system corresponds to the performance of the chip under test, allowing for a rapid determination of whether the system meets the testing requirements of the chip, thereby significantly reducing the difficulty and risk for users in building their own testing systems. The main KPI system is as follows: (1) Frequency range Given the system's operating frequency range, it is required to cover the DUT's operating range. For nonlinear testing, it is also required to cover the harmonic frequency range.

[0020] (2) Frequency accuracy The accuracy of the calibrated frequency.

[0021] (3) Output power range The range of minimum to maximum output power of the matching unit should cover the operating power range of the DUT as much as possible.

[0022] (4) Port harmonic suppression The purity of the system test signal was calibrated.

[0023] (5) Maximum test power The maximum power that can be input to the chip is an important metric in high-power testing, so it is listed separately.

[0024] (6) Effective noise floor Using the matching unit interface as a reference port, calibrate the receiver's noise floor, which should be at least 10dB lower than the DUT's output signal.

[0025] (7) Receive 3dB compression point Using the matching unit interface as a reference port, calibrate the maximum signal power that the system can test for linearity. This power must be greater than the output signal of the DUT.

[0026] (8) System dynamic range After microwave calibration, the dynamic range must be greater than the maximum power difference between the DUT's input and output. For example, for filter chips, the dynamic range must be greater than the chip's out-of-band rejection by 10dB; for amplified signals, the dynamic range must be greater than the chip's gain by 10dB.

[0027] (9) Harmonic order It can handle the maximum harmonic order of the DUT.

[0028] (10) Intermodulation order The maximum intermodulation order that can be handled by the DUT.

[0029] (11) Tuning range of reflection coefficient When performing power load traction tests, scan the maximum radius of the Simth circle graph of the reflection coefficient.

[0030] (12) Pulse broadband The minimum pulse width must be less than the pulse width at which the DUT operates.

[0031] (13) Intermediate frequency bandwidth The system is required to handle intermediate frequency signals with a bandwidth greater than that of the signal itself, but it often needs to balance test speed and system dynamic range, and generally will not use the maximum processing capacity.

[0032] (14) Number of channels The number of channels in the system.

[0033] (15) Wafer size The system can accommodate the largest possible size of microwave wafers.

[0034] (16) PAD spacing and accuracy When converting a matching unit to a coplanar waveguide, the tip spacing and precision must match the PAD ports of the chip.

[0035] (17) Voltage and current resolution The ability of bias voltage to supply voltage and current.

[0036] (18) Test speed Under DUT testing conditions, the system can test a single chip or a single wafer within a given timeframe. Many factors influence testing speed, including chuck movement speed, electrical unit scanning speed, switching speed, and matching unit matching speed, necessitating optimization and adjustment of the system's timing.

[0037] (19) Positioning resolution and repeatability During wafer testing, it is required to physically locate and move individual chips on the wafer, and the resolution and repeatability must meet the requirements for chip spatial movement.

[0038] (20) Effective directivity, effective source matching, effective payload matching, effective transmission tracking, effective reflection tracking After microwave calibration, the system's directivity, source matching, load matching, transmission tracking, and reflection tracking errors are considered. These errors do not need to be directly related to the chip's performance, but they collectively determine the uncertainty of the system's test results.

[0039] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A comprehensive performance testing device for microwave chips at the wafer level, characterized in that, include: One time base signal unit is used to provide the system's standard frequency reference; One local oscillator unit is used to generate and provide local oscillator signals to all receivers; M+1 signal source units, including M signal sources for connecting the test ports of the device under test (DUT) and one additional signal source, are used to generate M+1 microwave test signals. M circulators, each circulator connected in series after M signal source units, the circulators include a first type of circulator and a second type of circulator, the third port of the first type of circulator is connected to a high-sensitivity receiver, and the third port of the second type of circulator is connected to a high-power matched load. M couplers, each connected after a circulator, with its main output connected to a matching unit to connect to the DUT. Its forward coupling port and reverse coupling port are used to extract the forward incident signal and the reverse reflected / transmitted signal, respectively. 2M conventional receivers are used to receive the forward and reverse signals from the M channels extracted by the M couplers and perform down-conversion processing; N high-sensitivity receivers are used to receive and process ultra-low power signals; MN high-power matching loads are used to absorb signals transmitted toward the signal source; A gating switch, the moving end of which is connected to the output of source 0, and the two stationary ends of which are respectively connected to the test channels corresponding to two different type 1 circulators, is used to selectively inject the signal of source 0 into one of the two test channels; A wafer chuck unit is used to carry and hold the DUT; A four-dimensional motion unit is used to drive the wafer chuck unit to move in the X, Y, and Z translational directions and the θ rotational direction to adjust the DUT's attitude and contact position; M matching units are used to convert the microwave signal of the system into the coplanar waveguide signal input to the DUT; A standard component with pre-calibrated open circuit, short circuit, load, pass, and transmission states for system error calibration; An intermediate frequency (IF) processing sampling unit with 2M+N input channels is used for IF conditioning and analog-to-digital conversion of signals from all conventional and high-sensitivity receivers.

2. The microwave chip wafer-level performance comprehensive testing device according to claim 1, characterized in that, Also includes: The CPU control unit is used to control the opening and closing and switching of the signal source unit, four-dimensional motion unit, voltage source and switch, and to perform error compensation and parameter calculation on the sampled data based on the calibration data of the standard component. The power supply unit is used to power the entire device; Voltage source unit, used to provide additional voltage and logic control signals to DUT.

3. The microwave chip wafer-level performance comprehensive testing device according to claim 1, characterized in that, The local oscillator signal output by the local oscillator signal unit is power-divided to the 2M conventional receivers and the N high-sensitivity receivers; The N high-sensitivity receivers are equipped with switches and matching loads, which direct the signal to the load when not in operation; The standard component can be used to calibrate the signal power at the DUT contact point, calculate and compensate for microwave interference signals in the system, and correct the phase reference plane to the chip input position or half the through line length.

4. The microwave chip wafer-level performance comprehensive testing device according to claim 1, characterized in that, The motion speed and displacement accuracy of the four-dimensional motion unit are configured such that its motion speed matches the DUT electrical coupling stabilization time and the system electrical scanning speed, and the maximum cumulative value of its displacement error is not greater than the size of the DUT contact point.

5. The microwave chip wafer-level performance comprehensive testing device according to claim 1, characterized in that, When M=4, the signal source unit includes a first signal source, a second signal source, a third signal source, and a fourth signal source, corresponding to the first to fourth couplers respectively; there are two first-type circulators, corresponding to the first and fourth signal sources respectively; there are two second-type circulators, corresponding to the second and third signal sources respectively; the two static terminals of the gating switch are respectively connected to the test channels corresponding to the first and fourth signal sources; there are two high-sensitivity receivers, and the first and second high-sensitivity receivers are respectively connected to the third port of the first-type circulator; There are eight conventional receivers. The first coupler corresponds to the first and second conventional receivers, the second coupler corresponds to the third and fourth conventional receivers, the third coupler corresponds to the fifth and sixth conventional receivers, and the fourth coupler corresponds to the seventh and eighth conventional receivers.

6. A comprehensive performance testing method for microwave chips at the wafer level, characterized in that, Using the microwave chip wafer-level performance comprehensive testing device as described in claim 5, wherein M=4, the method includes the following steps: S1: The CPU control unit moves the wafer chuck through the four-dimensional motion unit, so that the input and output ports of the DUT are connected to the first matching unit and the fourth matching unit respectively; S2: Apply bias voltage to the DUT through the voltage source unit; S3: Turn on the first signal source, and the signal is loaded to the input port of the DUT through the first circulator, the first coupler, and the first matching unit; When the signal passes through the first coupler, part of the signal is coupled out and enters the first conventional receiver; The reflected signal from the DUT enters the first high-sensitivity receiver after passing through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The DUT's transmitted signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth coupler. When passing through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver. S4: Turn on the fourth signal source. The signal is applied to the input port of the DUT through the fourth circulator, the fourth coupler, and the fourth matching unit. When the signal passes through the fourth coupler, part of the signal is coupled out and enters the seventh conventional receiver; The reflected signal from the DUT enters the second high-sensitivity receiver after passing through the fourth matching unit, the fourth coupler, and the fourth circulator. When passing through the fourth coupler, part of the reverse signal is coupled out and enters the eighth conventional receiver. The reverse leakage signal of the DUT enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. S5: All receivers send the down-converted intermediate frequency signal to the intermediate frequency processing sampling unit for sampling. The CPU control unit performs vector error correction on the sampling data of all receivers in S2 and S4 based on the pre-stored calibration data. S6: Based on the corrected data, calculate the scattering parameters, derived coefficients, distortion parameters, and power parameters of the DUT; S7: Control the signal source to output a pulse signal, set the pulse width, duty cycle, frequency and power, repeat steps S1-S5, and obtain the power parameters and pulse parameters of the DUT through the corrected data; S8: Control the local oscillator signal scanning of the receiver so that the center frequency and source frequency of the receiver can be controlled separately. The intermediate frequency processing unit sets the intermediate frequency bandwidth. Repeat steps S1-S6 to obtain the spectrum parameters, nonlinear parameters and noise parameters of the DUT. S9: After repeating steps S1-S4, simultaneously turn on the first and fourth signal sources, load signals bidirectionally, and the first, second, seventh, and eighth conventional receivers work simultaneously; at this time, an artificial equivalent output standing wave is formed at the DUT output end. Adjust the phase and amplitude of the fourth signal source to scan the DUT output standing wave and obtain the power parameters of the DUT. S10: Turn off the first signal source, and the first and second conventional receivers and the second high-sensitivity receiver operate. Change the reference impedance of the first matching unit, and the second high-sensitivity receiver scans the noise gain that changes due to the system output impedance to obtain the noise parameters of the DUT. S11: Simultaneously turn on the first signal source and the auxiliary signal source, and switch the gating switch to combine the first signal source and the auxiliary signal source. At this time, it is equivalent to using a two-tone signal to excite the DUT. The signal is loaded to the input port of the DUT through the first circulator, the first coupler, and the first matching unit. When the signal passes through the first coupler, some of it is coupled out and enters the first conventional receiver; The reflected signal from the DUT enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When it passes through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The DUT's transmitted signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator. When passing through the fourth coupler, some of the signal is coupled out and enters the eighth conventional receiver. S12: Simultaneously turn on the fourth signal source and the auxiliary signal source, and switch the gating switch to combine the fourth signal source and the auxiliary signal source. At this time, it is equivalent to using a two-tone signal to excite the DUT in reverse. The signal is loaded to the output port of the DUT through the fourth circulator, the fourth coupler, and the fourth matching unit. When passing through the fourth coupler, some of the signal is coupled out and enters the seventh conventional receiver; The DUT reflected signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator. When it passes through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver. The reverse leakage signal of the DUT enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The parameters that can be tested at this time include distortion parameters and nonlinear parameters; S13: Turn on the first signal source and the second signal source. If the device under test is a mixer, connect the second signal source to the intermediate frequency port of the mixer. The second signal source serves as the intermediate frequency signal. The signal from the first signal source is loaded onto the input port of the DUT through the first circulator, the first coupler, and the first matching unit; when passing through the first coupler, part of the signal is coupled out and enters the first conventional receiver; the DUT reflected signal passes through the first matching unit, the first coupler, and the first circulator and enters the first high-sensitivity receiver; when passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The intermediate frequency (IF) signal is loaded onto the input port of the DUT through the second circulator, the second coupler, and the second matching unit; when passing through the second coupler, part of the signal is coupled out and enters the third conventional receiver; the reflected signal of the IF signal passes through the second matching unit and the second coupler, and when passing through the second coupler, part of the signal is coupled out and enters the fourth conventional receiver. The DUT's transmitted signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator. When passing through the fourth coupler, some of the signal is coupled out and enters the eighth conventional receiver. S14: The second signal source and the fourth signal source are turned on, and the second signal source is kept connected to the intermediate frequency port of the mixer as an intermediate frequency signal; The intermediate frequency (IF) signal is loaded onto the input port of the DUT through the second circulator, the second coupler, and the second matching unit; when passing through the second coupler, part of the signal is coupled out and enters the third receiver; the reflected signal of the IF signal passes through the second matching unit and the second coupler, and when passing through the second coupler, part of the signal is coupled out and enters the fourth conventional receiver. The reverse test signal of the DUT is loaded to the input port of the DUT through the fourth circulator, the fourth coupler, and the fourth matching unit; when passing through the fourth coupler, part of the signal is coupled out and enters the seventh conventional receiver; the DUT reflected signal enters the second high-sensitivity receiver through the fourth matching unit, the fourth coupler, and the fourth circulator; when passing through the fourth coupler, part of the signal is coupled out and enters the eighth conventional receiver. The reverse transmission signal enters the first high-sensitivity receiver through the first matching unit, the first coupler, and the first circulator. When passing through the first coupler, part of the signal is coupled out and enters the second conventional receiver. The parameters that can be tested at this time include nonlinear parameters, scattering parameters and derived coefficients, and spectral parameters; S15: The first, second, third, and fourth signal sources are turned on in turn, and the conventional receiver turns on scanning. If the device under test is a differential device, the first and second signal sources are turned on simultaneously, and the third and fourth signal sources are turned on simultaneously. At this time, the parameters that can be tested are the scattering parameters and the derived coefficients.

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