Research On A New Source Measurement Unit For Semiconductor Device Characteristic Testin

Semiconductor devices are the basic components that constitute electronic circuits.Its special performance determines that it plays an irreplaceable role in the field of electronic system design.The rapid development of semiconductor devices has made electronic products more and more powerful,making it possible for emerging applications such as artificial intelligence and autonomous driving,which have greatly promoted the development of human society.Suitable semiconductor devices can be used in different applications to truly play its role.This requires understanding the operating characteristics of each semiconductor device,and semiconductor testing equipment can detect the operating characteristics of the semiconductor device.As the semiconductor industry receives more and more attention,the development of semiconductor test equipment is also proceeding rapidly.Among them,the Source Measure Unit(SMU)is mainly used to test the I-V characteristics of semiconductor discrete devices,and is an indispensable part of semiconductor test equipment.This paper designs an SMU system for semiconductor device characteristic testing,including a high-precision SMU module,which uses an output source interface and an independent grounding unit measurement method.STM32F103RCT6 is used as the MCU control chip of this module.Among them,the high-precision ADC can collect bipolar potential for SMU circuit measurement,the high-precision DAC combined with the amplifier provides bipolar input signal for the SMU circuit,and the programmable analog switch is feedback from the switching power operational amplifier.The loop allows the SMU to switch freely between the two power output modes of voltage source and current source.It can test the characteristics of low-power semiconductor discrete devices,such as diodes,triodes,etc.;CNC high-voltage SMU power supply module,which uses flyback topology,combined with the knowledge of switching circuits and feedback control,can provide up to 1000 V high voltage by digital control.Test the breakdown characteristics of semiconductor discrete devices for power supply;the numerical control high-current SMU power supply module uses the principle of negative feedback control,combined with the output characteristics of the IGBT,and can be numerically controlled to obtain hundreds of amperes of current.This article also introduces in detail the working principle of each module of the SMU system and the simulation implementation using TINA-TI,and debugs and verifies each module,including the debugging of the functions of each discrete circuit of the high-precision SMU module and the test of the two terminals through the driver.The output characteristic curve of the device ordinary diode 1N4007 and the three-terminal device NPN transistor C1815 are displayed in the host computer LabView,and the corresponding data manual is compared to analyze the test results;the numerical control and boost function test of the numerical control high voltage SMU power supply module;the numerical control high current SMU module The proof of principle.Through the test of each module,the result shows that the SMU system meets the expected design goals.The SMU system designed in this topic can be used in university laboratories to facilitate students to test the characteristics of semiconductor discrete devices by themselves,and to learn related knowledge of semiconductor devices more intuitively,which has practical application and scientific research value.