Research And Design Of Radiation-resistant Static Ramdom Access Memory

With the continuous reduction of the characteristic size of integrated circuits and the decreasing of operating voltages,various radiation particles present in the space environment pose a serious threat to semiconductor devices.Various radiation effects(single-particle upset effect single-particle latch-up effect,total dose effect,etc.)may cause failure of the electronic device and pose a serious threat to the system.SRAM(static random access memory),which has the advantages of fast speed and low power consumption,is also widely used in various spacecraft.Therefore,SRAM not only needs to ensure its own functions and advantages,but also needs to have good radiation resistance.This topic originates from a space project and designs the anti-radiation reinforcement performance of SRAM.The most central part of SRAM is the storage unit.In this paper,compare and analyze the standard 6 tube storage unit and the DICE storage unit circuit,and the DICE unit is used as SRAM storage unit to improve the radiation resistance.The reinforcement measures for single particle latch and total dose effect are also taken on the map.The anti-radiation SRAM design is completed in a modular way.The work of this paper mainly has the following points:(1)Study the origin of space radiation particles,and analyze the mechanism of radiation effects of single particle upset,single particle transient,single-particle latch and total dose in detail.Summarize the common reinforcement techniques and shortcomings of SRAM.(2)SRAM is composed of CMOS devices,so use Sentaurus device simulation to complete the device modeling of NMOS transistor.Simulate its output characteristic curve and transfer characteristic curve,as well as the leakage pole current size after single particle incident,and the 6-Tube storage unit and the reinforced DICE storage unit are simulated by the pulse current signal of single particle incident.(3)Design the peripheral circuit matching with the DICE storage unit,including the row decoder,the pre-charging circuit,the sensitive amplifier circuit and the read-write control circuit.Set up the simulation environment to simulate and verify each module.All logic units used in the circuit(inverter,nor-gate,nand-gate,D flip-flop,etc.)are antiradiation structure.Sensitive amplifier uses three-mode redundant structure reinforcement.For single-particle latch effect and total dose effect,use guard-ring and surrounding-ring on the map.The design of 1Kbit radiation-resistant static memory is completed with a fully customized design process.