Different charging behaviors between electrons and holes in Si nanocrystals embedded in SiN_x matrix by the influence of near-interface oxide traps  

作　　者：方忠慧 江小帆 陈坤基 王越飞 李伟 徐骏 

机构地区：[1]State Key Laboratory of Solid State Microstructures and School of Physics, Nanjing University

出　　处：《Chinese Physics B》2015年第1期457-461,共5页中国物理B（英文版）

基　　金：Project supported by the National Basic Research Program of China(Grant No.2010CB934402);the National Natural Science Foundation of China(Grant No.11374153)

摘　　要：Si-rich silicon nitride films are prepared by plasma-enhanced chemical vapor deposition method, followed by thermal annealing to form the Si nanocrystals（Si-NCs） embedded in Si Nx floating gate MOS structures. The capacitance–voltage（C–V）, current–voltage（I–V）, and admittance–voltage（G–V） measurements are used to investigate the charging characteristics. It is found that the maximum flat band voltage shift（△VFB） due to full charged holes（～ 6.2 V） is much larger than that due to full charged electrons（～ 1 V）. The charging displacement current peaks of electrons and holes can be also observed by the I–V measurements, respectively. From the G–V measurements we find that the hole injection is influenced by the oxide hole traps which are located near the Si O2/Si-substrate interface. Combining the results of C–V and G–V measurements, we find that the hole charging of the Si-NCs occurs via a two-step tunneling mechanism. The evolution of G–V peak originated from oxide traps exhibits the process of hole injection into these defects and transferring to the Si-NCs.Si-rich silicon nitride films are prepared by plasma-enhanced chemical vapor deposition method, followed by thermal annealing to form the Si nanocrystals（Si-NCs） embedded in Si Nx floating gate MOS structures. The capacitance–voltage（C–V）, current–voltage（I–V）, and admittance–voltage（G–V） measurements are used to investigate the charging characteristics. It is found that the maximum flat band voltage shift（△VFB） due to full charged holes（～ 6.2 V） is much larger than that due to full charged electrons（～ 1 V）. The charging displacement current peaks of electrons and holes can be also observed by the I–V measurements, respectively. From the G–V measurements we find that the hole injection is influenced by the oxide hole traps which are located near the Si O2/Si-substrate interface. Combining the results of C–V and G–V measurements, we find that the hole charging of the Si-NCs occurs via a two-step tunneling mechanism. The evolution of G–V peak originated from oxide traps exhibits the process of hole injection into these defects and transferring to the Si-NCs.

关 键 词：silicon nanocrystals memory different charging of electrons and holes oxide traps admittancevoltage characteristics 

分 类 号：TB383.1[一般工业技术—材料科学与工程]