Design Of Integrated Circuits Test System For 3D NAND Flash Of DC Parameter

Integrated circuit testing is an important method of verifying the quality and performance of integrated circuits.It is an indispensable part of the entire production process throughout the entire process of design,manufacture,packaging and application of integrated circuits.The test of DC parameters plays an important role in the chip test,which is used to test whether the electrical performance of the chip meets the design requirements.With the rapid development of the integrated circuit industry,the integration of chips is getting higher and higher,and the cost of chip test accounts for an increasing proportion of the total production cost.Therefore,the high-precision,low-cost DC parameter automatic test system has become an inevitable requirement for today's integrated circuit test.In order to design a DC parameter test system that can meet the test requirements of 3D NAND Flash memory chips,we have studied the architecture and working principle of 3D NAND Flash chips,as well as the principle and method of integrated circuit testing,and proposed a low-cost implementation of 3D NAND Flash DC parameter test system based on FPGA.A programmable voltage source with sixteen regulated voltage outputs was used to power the device under test.Self-calibrating precision measurement unit circuit with discrete components was applied to force excitation and measure response.Finally,the system can realize the force and measurement of the maximum voltage ±30V and current ±500m A.The system master unit FPGA is programmed using the Verilog HDL hardware description language to complete the logic control of the system hardware,including test mode settings,range selection,calibration configuration,and so on.In order to improve the test accuracy,the system used the combination of hardware and software to calibrate the test.The high-precision measuring instruments are used to externally calibrate the system.Then,according to the measured data,an appropriate offset is added to correct the DAC conversion error.Finally,the least squares method is used to correct the linearity error of the system.The actual test experimental data shows that compared with the test system built by the dedicated integrated chip,the DC parameter test system proposed in this paper has achieved higher test accuracy and wider test range.The relative error of the calibrated test system is less than 0.03%,the minimum current accuracy is 6n A,which can meet the functions of DC parameter test of 3D flash chip,and has high versatility.The hardware cost only accounts for about two-thousandths of foreign automatic test equipment,which can effectively alleviate the high test cost in R&D of enterprises,and is conducive to the development of domestic related enterprises.