Charge storage characteristics of Ni nanocrystals formed by synchronous crystallization  

作　　者：程佩红 黄仕华 陆昉 

机构地区：[1]Physics Department Zhejiang Normal University [2]Surface Physics National Key Laboratory Fudan University

出　　处：《Journal of Semiconductors》2014年第10期17-22,共6页半导体学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(No.61076055);the Open Project Program of Surface Physics Laboratory(National Key Laboratory)of Fudan University(No.KL2011_04)

摘　　要：The rapid thermal annealing （RTA） nano-crystallization method is widely used in the metal nanocrystal fabrication process. However, the high temperature （usually 600 900 ℃） in the RTA process will worsen the per- formance and reliability of devices. A novel method has been proposed to grow metal nanocrystal by synchronous in situ nano-crystallization of metal thin film （SINC）, which is able to resolve the problems mentioned above. Com- pared with Ni nanocrystals （NCs） formed by RTA, Ni NCs prepared by SINC can obtain more energy to crystallize, and its crystallization temperature is greatly reduced. A large memory window （2.78 V） was observed for Ni NCs deposited by SINC at 300 ℃. However, the largest window is only 1.26 V for Ni NCs formed by RTA at 600 ℃. A large change （from 0.20 to 4.59 V） of the memory window was observed while the operation voltage increased from 0 to 4-10 V, which is due to an occurrence of strong carrier trapping in Ni NCs. Flat-band voltage shift rapidly increases to its saturation value, which indicates that electron/hole trapping in Ni NCs mainly occurs at the initial stage of the program/erase process. A theoretical model was proposed to characterize the charging and discharging processes.The rapid thermal annealing （RTA） nano-crystallization method is widely used in the metal nanocrystal fabrication process. However, the high temperature （usually 600 900 ℃） in the RTA process will worsen the per- formance and reliability of devices. A novel method has been proposed to grow metal nanocrystal by synchronous in situ nano-crystallization of metal thin film （SINC）, which is able to resolve the problems mentioned above. Com- pared with Ni nanocrystals （NCs） formed by RTA, Ni NCs prepared by SINC can obtain more energy to crystallize, and its crystallization temperature is greatly reduced. A large memory window （2.78 V） was observed for Ni NCs deposited by SINC at 300 ℃. However, the largest window is only 1.26 V for Ni NCs formed by RTA at 600 ℃. A large change （from 0.20 to 4.59 V） of the memory window was observed while the operation voltage increased from 0 to 4-10 V, which is due to an occurrence of strong carrier trapping in Ni NCs. Flat-band voltage shift rapidly increases to its saturation value, which indicates that electron/hole trapping in Ni NCs mainly occurs at the initial stage of the program/erase process. A theoretical model was proposed to characterize the charging and discharging processes.

关 键 词：metal nanocrystal memory synchronously crystallization C-V characteristics 

分 类 号：TP333[自动化与计算机技术—计算机系统结构] TB383.1[自动化与计算机技术—计算机科学与技术]