Research Of Design Reinforcement Method For Radiation-Hardened SRAM Cell Based On 65nm Bulk Silicon CMOS Process

In recent years,semiconductor technology has been developing rapidly.And the dimension of CMOS processes keeps shrinking.It makes the reliability of the integrated device electronics which is affected by radiation face more serious challenges.Besides,with the circuit's supply voltage and node capacitance decreasing,the memory,as an important part of the integrated circuit,will bring a higher and higher sensitiveness of to single event effects(SEE).Therefore,it's very important to study the radiation resistance for memory.A kind of RHED(Radiation Hardened Enhanced DICE)SRAM cell structure is proposed in this paper,based on the analysis of the existing radiation-hardened Static Random Access Memory(SRAM)and the improvements of the traditional DICE(the dual interlocked storage cell)structure.Compared with the DICE cell,the RHED cell not only improves the immunity of the circuit to the Single-Event Multiple-Node Upsets(SEMNUs),but also greatly increases the Head Static Noise Margin(HSNM)of the circuit.In addition,the write margin(WM)and power consumption of the RHED cell have been partially improved as well.In the SMIC 65nm CMOS process,the SPICE software is used to simulate circuit-level simulations.The results show that the dynamic power consumption of the proposed RHED cell has reduced 38.6%and the static power consumption of the proposed RHED cell has reduced 18.4%respectively.The WM has increased 33%.Most of all,HSNM has increased 371%.In terms of radiation-hardened,the double-exponential current source is used to analyze the sensitivity of each node pair in the RHED cell to the single event effects.The results of the analysis are a great guide to the layout of the cell.Through the improvement of circuit structure and reasonable layout design,the radiation resistance of the proposed RHED cell is greatly improved.The radiation resistance performance is simulated and verified by Sentaurus TCAD software.And the simulation results show that the data stored in the RHED cell will be able to keep the same when the linear energy transfer(LET)of the incident particles reaches 60MeV-cm2/mg and the incident particles comes from different directions and angles.However,the upset threshold of the DICE cell is only 1MeV-cm2/mg under the same simulation settings and similar layouts.Therefore,the RHED cell will also make a more significant improvement in radiation resistance.