The Charge Storage of Doubly Stacked Nanocrystalline-Si based Metal Insulator Semiconductor Memory Structure

Xiang Wang, Chao Song, Yanqing Guo, Jie Song, Rui Huang

Department of Physics and Electronic Engineering, Hanshan Normal University, Chaozhou, People’s Republic of China.

DOI: 10.4236/mnsms.2013.31B006                

Abstract

Doubly stacked nanocrystalline-Si (nc-Si) based metal insulator semiconductor memory structure was fabricated by plasma enhanced chemical vapor deposition. Capacitance-Voltage (C-V) and capacitance-time (C-t) measurements were used to investigate electron tunnel, storage and discharging characteristic. The C-V results show that the flatband voltage increases at first, then decreases and finally increases, exhibiting a clear deep at gate voltage of 9 V. The de-creasing of flatband voltage at moderate programming bias is attributed to the transfer of electrons from the lower nc-Si layer to the upper nc-Si layer. The C-t measurement results show that the charges transfer in the structure strongly de-pends on the hold time and the flatband voltage decreases markedly with increasing the hold time.

Keywords

nc-Si dots; Capacitance-Voltage Measurement; Storage

Conflicts of Interest

The authors declare no conflicts of interest.

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