Multi-project wafer automatic test system and method

Abstract

The invention relates to the field of semiconductor testing, and discloses a multi-project wafer automatic testing system which comprises testing software, testing hardware integration and probe station equipment. The test software is integrally connected with the probe station equipment and the test hardware through a communication interface; and the test hardware integration is connected with the probe station equipment through the test interface. According to the invention, through combination of integrated hardware and flexible software, efficient and automatic testing of a multi-project wafer is realized; compared with a conventional test system, through friendly test software interaction, automatic identification and needle insertion can be subsequently realized to complete the whole test process by only performing one-time multi-chip parameter information importing and one-time manual intervention needle insertion positioning under the multi-project wafer condition, so that the complexity of multi-project wafer test operation is reduced, and the test efficiency is improved. The multi-project wafer needling test stability and the chip switching test efficiency are effectively improved, meanwhile, excellent data processing and display functions are provided, and measurement results can be conveniently and dynamically checked and analyzed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor testing, in particular to a multi-project wafer automatic testing system and method. BACKGROUND

[0002] Microwave chips are core devices for communication, radar, sensors and other supporting devices, and their performance directly affects the overall performance of the devices. Since the front-end semiconductor process cannot guarantee 100% yield, wafer-level testing is needed after tape-out to remove defective products. Wafer-level testing is mainly used to obtain early chip characteristics and reliability data analysis. Compared with product reliability and failure verification after product design is finalized, wafer testing can intervene early, greatly saving development time and cost.

[0003] With the evolution of semiconductor technology to nanoscale, the integration of chips grows exponentially, and a single wafer can contain thousands to tens of thousands of dies. The birth of multi-project wafers (MPW) effectively reduces the cost of designing chips, that is, multiple chips are produced on one wafer to reduce chip manufacturing costs. However, the tape-out of MPW also increases the difficulty and cost of on-chip testing. The manual testing or single-point testing method of traditional testing systems cannot meet the efficiency and accuracy requirements, and higher requirements are put forward for the realization of MPW automatic testing.

[0004] A wafer test system (WTS) is a key device in the wafer-level testing process, which is used to test the electrical performance of each die on the wafer before chip cutting and packaging. Its purpose is to screen out chips with functional defects or performance that do not meet the standards, avoid waste of subsequent packaging and testing resources, improve yield and reduce production cost. The testing system on the market is generally provided by probe station manufacturers, which has some shortcomings: first, the degree of integration is low, technical barriers are set up between instrument manufacturers, and each testing system only supports or depends on its own instrument, making it impossible to build flexibly and causing system redundancy; second, the automation efficiency is low, the testing system software has fixed and incomplete functions, and cannot dynamically adapt to different wafer batch parameters in actual application, cannot realize multi-project selective automatic testing, and has long manual intervention time and low testing efficiency. SUMMARY

[0005] In view of the above technical deficiencies, the technical problem to be solved by the present application is to provide a multi-project wafer automatic test system and method, based on a multi-project wafer test process, by integrating wafer parameter management, instrument control, test data management and other functions, the problems of manual operation affecting test stability and consistency in multi-project testing are overcome, the problems of system redundancy, complex operation and low efficiency of the existing wafer test system are solved, and the test requirements of multi-project wafer integration and automation are met.

[0006] To solve the above technical problems, the present application adopts the following technical solutions: the present application provides a multi-project wafer automatic test system, comprising: test software, test hardware integration and probe station equipment; the test software is connected with the probe station equipment and the test hardware integration through a communication interface; the test hardware integration is connected with the probe station equipment through a test interface.

[0007] Further, the test software comprises a test execution master module, a communication module, a data management module, a function module 1 and a function module 2; The test execution master module is used for coordinating and controlling the entire automatic test process of MPW. The communication module is used for receiving control instructions sent by the function module 1 and test instructions sent by the function module 2, and sending the two instructions to the probe station equipment and the test hardware integration respectively, and receiving state information and test data returned by the probe station equipment and the test hardware integration; The data management module is used for receiving, processing, analyzing and storing test data sent by the communication module.

[0008] Further, the function module 1 comprises an MPW parameter configuration module and a probe station control module; The MPW parameter configuration module is connected with the probe station control module, and is used for setting MPW related parameters and making Map files; The probe station control module is connected with the communication module, and is used for sending the probe station control instructions to the probe station equipment for corresponding operation, and receiving state information of the probe station equipment.

[0009] Further, the function module 2 comprises a test parameter configuration module and a test hardware control module; The test parameter configuration module is connected with the test hardware control module, and is used for setting test hardware related parameters and test cases; The test hardware control module is connected with the communication module, and is used for sending the test hardware test instructions to the test hardware integration for testing, and receiving test hardware state information and collected test data.

[0010] Further, the test hardware integration includes a test instrument, a switch matrix and a control device; The test instrument includes a vector network analyzer, a spectrum analyzer, an oscilloscope and a direct current stabilized power supply, and is used for electrical characteristic parameter testing. The switch matrix is used for channel switching, instrument input and output switching and attenuator switching. The control device includes a PCIE multifunctional wave control box, and is used for controlling the microwave chip to test according to the formulated working condition.

[0011] Further, the probe station device includes a probe station and a motion control device.

[0012] A multi-project wafer automatic testing method, comprising: The test hardware integration part is built and instrument calibration is completed, the probe station in the probe station device is calibrated, radio frequency probes, wafer leveling positioning, fluctuation calibration and needle depth testing are completed; Information generation control instructions and test instructions are set in the MPW parameter configuration module and the test parameter configuration module respectively, and the communication addresses of the probe station and the test hardware are set in the communication module, which are used for instruction sending and data receiving; After starting testing, the test execution main control module schedules tasks and sends instructions to the probe station and the test hardware, automatically completes needle insertion and data acquisition, the test data management module analyzes and stores results in real time, and the test state is displayed in a graphical manner; After single-chip testing is completed, the test execution main control module automatically judges whether the current chip is the last chip of the selected project, if not, moves to the next chip to perform testing operation, if yes, ends the current testing, and the data management module generates a final test data file and a result file; After the current project is completed, the test execution main control module prompts whether to switch to other projects, if not, the testing process is ended, if yes, the new project parameters are automatically analyzed and the Die position is repositioned, the testing process is repeated, and multi-project wafer step-by-step testing is realized.

[0013] The present application has the following advantages: 1. The multi-project wafer automatic testing system can set multiple project chip coordinates, sizes and other information at one time, and automatically analyzes and identifies in the testing process, solves the problem of multiple manual intervention for importing different wafer Map graphs and repositioning needle insertion, realizes rapid and simple selective testing of multiple projects, meets the current demand for integrated and automated multi-project wafer testing system, and realizes stable and efficient automatic testing of multiple projects.

[0014] 2. The integrated design of the test hardware overcomes the distributed redundancy problem of traditional test systems. It can automatically parse and process parameter information according to the test instructions issued by the test software, reduce the time of multiple manual operations, realize integrated automatic testing of test parameters, and improve the stability and consistency of multi-item wafer testing.

[0015] 3. The flexible testing software overcomes the problem of fixed and single functions in traditional testing systems. It can quickly set and execute test plans and facilitate switching between multiple wafer chips. It realizes real-time equipment control, data acquisition and processing, test result analysis and map display during the testing process, improving the convenience and efficiency of multi-project wafer testing. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a block diagram of a multi-project automated wafer testing system according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of a multi-project wafer testing workflow according to an embodiment of the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] This invention discloses a multi-item automated wafer testing system, such as... Figure 1 As shown, the multi-project automated wafer testing system includes test software, integrated test hardware, and probe station equipment; the test software is connected to the probe station equipment and integrated test hardware via a communication interface; the integrated test hardware is connected to the probe station equipment via a test interface.

[0021] In the embodiment, the test software includes a test execution master module, a communication module, a data management module, a function module 1 and a function module 2. The test execution master module is used for coordinating and controlling the whole automatic test process, including test task scheduling, test case execution, system configuration management and the like. The communication module is used for receiving the control instruction sent by the function module 1 and the test instruction sent by the function module 2, and sending the instruction to the probe station device and the test hardware integration respectively; and simultaneously receiving the state information and test data returned by the probe station device and the test hardware integration. The data management module is used for receiving the test data sent by the communication module, including test data processing, analysis, display and result file generation. During the test process, the received test data is processed in real time, and is analyzed and judged according to the preset index judgment condition, and the result is displayed on the software interface in an intuitive manner and is saved.

[0022] Further, the function module 1 includes an MPW parameter configuration module and a probe station control module. The MPW parameter configuration module is used for setting multi-project wafer related parameters and Map file making, including wafer size, flat edge / notch angle, edge width, Die size, Die inner chip distribution, Sub Die size, quantity and the like. For the multi-project wafer, the coordinates and size of the multi-project microwave chip can be set in the same layout to realize a complete multi-project Map graph. The probe station control module is used for generating probe station control instructions, including up and down piece, contact separation, Die & Sub Die movement, calibration fluctuation and the like. Different types of probe stations have similar wafer test processes. In order to realize general control design, the main operation program control instructions of different types of probe stations are programmed into the instruction set, and the control instructions are automatically matched by selecting the type of probe station. The probe station control instructions are sent to the probe station device through the communication module to perform corresponding operation, and the state information of the probe station device is received, so as to automatically realize the movement positioning and pinning of the multi-target microwave chip sub die, thereby solving the difficulty of manual intervention in multi-project test.

[0023] Further, the function module 2 includes a test parameter configuration module and a test hardware control module. The test parameter configuration module is used for setting test hardware related parameters and test cases, including test instrument communication address, test item, test range and qualified interval and the like. The test hardware control module is used for generating test hardware test instructions. After the test starts, the test hardware test instructions are sent to the test hardware integration through the communication module, and the test instrument can automatically test and collect according to the test instructions. After the test is completed, the communication module sends the test data to the data management module.

[0024] In this embodiment, the probe station equipment mainly includes a probe station and a motion control device. It should be noted that the probe station includes semi-automatic and fully automatic probe stations, including but not limited to brands such as MPI and TSK. Any probe station that can be used with testing software and is suitable for wafer testing falls within the protection scope of this invention. For the sake of brevity, not all possible probe stations are listed here. During testing, the probe station equipment receives probe station control commands sent by the communication module to complete the corresponding operations.

[0025] In this embodiment, the integrated test hardware includes test instruments, a switch matrix, and a control device. The test instruments include a vector network analyzer, a spectrum analyzer, an oscilloscope, and a DC regulated power supply for testing electrical characteristic parameters. It should be noted that any test instrument that can be used in conjunction with the test software and is suitable for wafer testing falls within the scope of this invention. For simplicity, not all possible test instruments are listed here. The switch matrix includes multiple input / output ports, including channel switching, instrument input / output switching, and attenuator switching functions, used to establish corresponding microwave paths between the ports of the chip under test and the ports of each test instrument. Only one connection is needed to achieve integrated testing of multiple parameters. The control device includes a PCIe multi-function wave controller box, used to control the microwave chip to be tested according to specified operating conditions.

[0026] like Figure 2 As shown, the workflow of this embodiment is as follows: 1) To ensure the accuracy of wafer testing, the test hardware integration and probe station equipment preparation must be completed before testing begins. First, the test hardware integration should be built according to the test requirements. Then, the test instruments should be connected and calibrated item by item according to their different test functions. After calibration, the probe station in the probe station equipment should be operated. First, the RF probes should be calibrated to ensure measurement accuracy during batch testing. Second, wafer loading, leveling, and home die positioning operations should be performed to ensure that the Chuck movement does not cause offset during testing. Next, wafer undulation calibration should be performed to avoid loss or deviation in wafer test performance caused by using only the same probe depth. Finally, probe testing should be performed to determine the probe height and avoid wafer scratches or probe damage.

[0027] 2) Open the testing software. In the MPW parameter configuration module, set the wafer information, die information, chip information, and the distribution, coordinates, and dimensions of the die and sub-dies for a certain type of multi-project wafer. This is used to generate map file information and probe station coordinate movement control commands. In the test parameter configuration module, set the test indicators, test frequencies, test stimuli, and other conditions for the multi-project microwave chip. This is used to generate test cases and test hardware test commands. In the communication module, set the communication addresses of the probe station and test hardware for sending commands and receiving data.

[0028] 3) In the test software interface, select any project and click "Start Test". The test execution main control module schedules test tasks and allocates test resources according to the multi-project wafer test process; the data management module creates a data storage file; the communication module sends probe station control commands to the probe station device; the probe station parses the commands and automatically moves to the first chip under test of the selected project for probe insertion; the communication module sends test hardware test commands to the test hardware integration; the test hardware parses the commands and automatically controls the test instruments to collect data according to the test cases; after the data collection is completed, the test data is sent to the data management module through the communication module; the data management module processes, analyzes, and stores the test data, and displays the results graphically on the software interface; the interface sequentially displays the total number of tests, Pass, Fail, pass rate, single-chip test time, and a result map; 4) After a single chip test is completed, the communication module returns a test completion message. The test execution control module determines whether the current chip is the last one selected for the project. If not, it automatically moves to the next chip to perform the test operation; otherwise, the current test ends, and the data management module generates the final test data file and result file. It should be noted that during repeated probe pricking tests, the probe may pick up gold dust from the pad, potentially causing probe instability and affecting test results. Therefore, periodic probe cleaning is necessary. The test execution control module will automatically pause the test after the preset number of pricking attempts has been reached, control the probe station to perform a probe cleaning operation, and resume testing only after the operation is completed.

[0029] 5) Further, the test software marks the microwave chips for different projects according to the set wafer parameter information. After completing the test of all chips of the selected projects on the multi-project wafer, the test execution main control module automatically prompts whether to switch to the next project for testing. If yes, the test software automatically parses the relevant parameter information of the selected project and generates corresponding control commands, which are transmitted to the test hardware integration and probe station equipment through the communication module. The probe station automatically moves to the die position of the first chip under test of the selected project for identification, positioning and probe testing, repeating the previous test process. If not, the current test ends.

[0030] It should be noted that during testing, sometimes contamination on the probe surface or a thinner section of the wafer can prevent the probe from perfectly contacting the chip's pads, leading to inaccurate test data, failure to meet process compliance requirements, and misjudgments. However, manually testing these chips would reduce the overall efficiency of wafer testing. The testing software includes an NG (Not From Good) retest function. In this mode, simply import the result file generated during the initial test. The data management module automatically analyzes the chip binning in the result file, locating the chips with performance defects and their positions. The test execution main control module then retests the defective chips based on the analyzed information, following the same testing procedure as the normal test. After all defective chips have been retested, the new data generated from the retest replaces the corresponding data in the initial test result file, generating the final result file.

[0031] Therefore, this invention provides a multi-project wafer automated testing system that achieves efficient automated testing of multi-project wafers through a combination of integrated hardware and flexible software. Compared to conventional testing systems, through user-friendly testing software interaction, in the case of multi-project wafers, only one import of multi-chip parameter information and one manual intervention for probe positioning are required. Subsequent automatic identification and probe placement complete the entire testing process, reducing the complexity of multi-project wafer testing operations and effectively improving the stability of probe testing and chip switching testing efficiency. It also provides excellent data processing and display functions, facilitating dynamic viewing and analysis of measurement results.

[0032] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multiple project wafer automatic test system, characterized by, The system comprises: test software, test hardware integration and probe station equipment; the test software is connected with the probe station equipment and the test hardware integration through a communication interface; and the test hardware integration is connected with the probe station equipment through a test interface.

2. The multi-project wafer automatic test system according to claim 1, wherein the test software comprises a test execution master module, a communication module, a data management module, a functional module 1 and a functional module 2; the test execution master module is used for coordinating and controlling the whole automatic test process of the MPW; the communication module is used for receiving a control instruction sent by the functional module 1 and a test instruction sent by the functional module 2, and sending the two instructions to the probe station equipment and the test hardware integration respectively, and receiving state information and test data returned by the probe station equipment and the test hardware integration; and the data management module is used for receiving and processing, analyzing and storing the test data sent by the communication module.

3. The multi-project wafer automatic test system according to claim 2, wherein the functional module 1 comprises an MPW parameter configuration module and a probe station control module; the MPW parameter configuration module is connected with the probe station control module, and is used for setting MPW related parameters and making a Map file; and the probe station control module is connected with the communication module, and is used for sending the probe station control instruction to the probe station equipment to perform corresponding operation, and receiving state information of the probe station equipment.

4. The multi-project wafer automatic test system according to claim 2, wherein the functional module 2 comprises a test parameter configuration module and a test hardware control module; the test parameter configuration module is connected with the test hardware control module, and is used for setting test hardware related parameters and test cases; and the test hardware control module is connected with the communication module, and is used for sending the test hardware test instruction to the test hardware integration to perform test, and receiving test hardware state information and collected test data.

5. The multi-project wafer automatic test system according to claim 1, wherein the test hardware integration comprises test instruments, a switch matrix and a control device; the test instruments comprise a vector network analyzer, a spectrum analyzer, an oscilloscope and a direct current stabilized power supply, and are used for electrical characteristic parameter test; the switch matrix is used for channel switching, instrument input and output switching and attenuator switching; and the control device comprises a PCIE multifunctional wave control box, and is used for controlling a microwave chip to perform test according to a formulated working condition; and the probe station equipment comprises a probe station and a motion control device.

7. An automatic test method based on the multi-project wafer automatic test system according to any one of claims 1 to 6, wherein the test hardware integration part is built and instrument calibration is completed, the probe station in the probe station equipment is calibrated, radio frequency probes are calibrated, wafer leveling and positioning are performed, fluctuation calibration and needle depth test are performed. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 6. The multiple project wafer automatic test system of claim 1, wherein, ​ ​ ​ Information generation control instructions and test instructions are set in the MPW parameter configuration module and the test parameter configuration module respectively, and communication addresses of the probe station and the test hardware are set in the communication module for sending instructions and receiving data; After starting the test, the test execution main control module schedules tasks and sends instructions to the probe station and the test hardware, automatically completes needle insertion and data acquisition, the test data management module analyzes and stores results in real time, and the test state is displayed graphically; After single-chip testing is completed, the test execution main control module automatically judges whether the current chip is the last chip of the selected project, if not, automatically moves to the next chip to perform the test operation, if yes, ends the current test, and the data management module generates a final test data file and a result file; After completing the current project, the test execution main control module prompts whether to switch to other projects, if not, the test process ends, if yes, automatically parses new project parameters and repositions the Die position, repeats the test process, and realizes step-by-step testing of multiple project wafers.

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