Comparison between N_2 and O_2 anneals on the integrity of an Al_2O_3/Si_3N_4/SiO_2/Si memory gate stack  

作　　者：褚玉琼 张满红 霍宗亮 刘明 

机构地区：[1]Institute of Microelectronics, Chinese Academy of Sciences [2]School of Electrical and Electronic Engineering, North China Electric Power University

出　　处：《Chinese Physics B》2014年第8期172-176,共5页中国物理B（英文版）

基　　金：Project supported in part by the National Basic Research Program of China(Grant Nos.2010CB934200 and 2011CBA00600);the National Natural Science Foundation of China(Grant Nos.61176073 and 61176080);the Director’s Fund of the Institute of Microelectronics,Chinese Academy of Sciences

摘　　要：In this paper the endurance characteristics and trap generation are investigated to study the effects of different postdeposition anneals （PDAs） on the integrity of an Al2O3/Si3N4/SiOz/Si memory gate stack. The flat-band voltage （Vfb） turnarounds are observed in both the programmed and erased states of the N2-PDA device. In contrast, this turnaround is observed only in the erased state of the O2-PDA device. The Vfb in the programmed state of the O2-PDA device keeps increasing with increasing program/erase （P/E） cycles. Through the analyses of endurance characteristics and the low voltage round-trip current transients, it is concluded that in both kinds of device there are an unknown type of pre-existing characteristic deep traps and P/E stress-induced positive oxide charges. In the O2-PDA device two extra types of trap are also found： the pre-existing border traps and the P/E stress-induced negative traps. Based on these four types of defects we can explain the endurance characteristics of two kinds of device. The switching property of pre-existing characteristic deep traps is also discussed.In this paper the endurance characteristics and trap generation are investigated to study the effects of different postdeposition anneals （PDAs） on the integrity of an Al2O3/Si3N4/SiOz/Si memory gate stack. The flat-band voltage （Vfb） turnarounds are observed in both the programmed and erased states of the N2-PDA device. In contrast, this turnaround is observed only in the erased state of the O2-PDA device. The Vfb in the programmed state of the O2-PDA device keeps increasing with increasing program/erase （P/E） cycles. Through the analyses of endurance characteristics and the low voltage round-trip current transients, it is concluded that in both kinds of device there are an unknown type of pre-existing characteristic deep traps and P/E stress-induced positive oxide charges. In the O2-PDA device two extra types of trap are also found： the pre-existing border traps and the P/E stress-induced negative traps. Based on these four types of defects we can explain the endurance characteristics of two kinds of device. The switching property of pre-existing characteristic deep traps is also discussed.

关 键 词：charge trapping memory post deposition anneal ENDURANCE TRAPS 

分 类 号：O469[理学—凝聚态物理]