脉冲应力增强的NMOSFET's热载流子效应研究

 本文研究了交流应力下的热载流子效应,主要讨论了脉冲应力条件下的热空穴热电子交替注入对NMOSFET's的退化产生的影响.在脉冲应力下,阈值电压和跨导的退化增强.NMOSFET's在热空穴注入后,热电子随后注入时,会有大的退化量,这可以用中性电子陷阱模型和脉冲应力条件下热载流子注入引起的栅氧化层退化来解释.本文还定量分析研究了NMOSFET's退化与脉冲延迟时间和脉冲频率的关系,并且给出了详细的解释.在脉冲应力条件下,器件的热载流子退化是由低栅压下注入的热空穴和高栅压下热电子共同作用的结果.

Study on Pulse Stress Enhanced Hot-Carrier Effects in NMOSFET's

Hot-carrier effects under AC(Alternating Current)stress are investigated in this paper.Alternative hot-hole and hot-electron injection effects on the degradation of NMOSFET's under pulse stress are discussed mainly.Enhanced degradation appears in both threshold voltage and transconductance under pulse stress.NMOSFET's after hot-hole injection followed by hot-electron injection produce serious degradation,which can be explained by neutral-electron-trap model and hot-carrier-induced gate oxide degradation under pulse stress.The pulsed delay time and pulse frequency effects on NMOSFET's degradation are investigated and analyzed quantitatively,and a detailed explanation is also given out.Under pulse stress,the hot-carrier-induced device degradation is caused by the cooperation of hot holes at low voltage and hot electrons at high voltage.