超深亚微米器件总剂量辐射效应三维数值模拟

Three-dimensional simulation of total dose effects on ultra-deep submicron devices

本文分析了浅槽隔离(STI)结构辐射诱导电荷的分布情况,给出一种模拟超深亚微米器件总剂量辐射效应的新方法.研究结果表明,如果在栅附近沿着STI侧墙不加辐照缺陷,仿真出的0.18μm超深亚微米晶体管亚阈区I-V特性没有反常的隆起,并且能够很好地反映试验结果.在研究总剂量辐照特性改善方面,在剂量不是很大的情况下,采用超陡倒掺杂相对于均匀掺杂能有效地减小辐照所引起的泄漏电流.如果采用峰值(Halo)掺杂,不仅有利于提高超深亚微米器件的抗辐照能力,而且在大剂量的情况下,可以得到明显的效果.

The radiation-induced charge distribution in shallow-trench isolation（STI） structures is analyzed in this paper.We present a new approach for modeling total dose effect of ultra-deep submicron transistors.The results show that,when there is no radiation-induced charge in top100 nm of the trench-silicon interface,the simulation results of 0.18μm ultra-deep submicron transistors show that the I-V sub-threshold does not produce the hump,and yield good agreement with experiments.On the aspect of the improvement on total ionizing dose,the leakage current of MOSFET with delta doping can be effectively reduced than with the uniform doping profile under lower radiation dose.If the Halo doping is adopted in landscape orientation,the total dose of ultra-deep submicron transistors can be improved.This improvement is evident even at higher irradiation dose.