X. WANG ET AL.
Copyright © 2013 SciRes. MNSMS
4. Conclusions
In summary, doubly stacked nc-Si based MIS memory
structure was fabricated by plasma enhanced chemical
vapor deposition. C-V and C-t measurement was used to
Figure 3. The programming bias dependence of flatband voltage
under different hold times.
investigate electron storage and discharging in the struc-
ture. The C-V experiment results show that the flatband
voltage first increases, then decreases and finally in-
creases, exhibiting a claer deep at gate voltage of 9 V.
The decreasing of flatband voltage at moderate pro-
gramming 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 depends on the hold time.
5. Acknowledgemen t s
The authors would like to acknowledge the financial
support of Natural Science Foundation of Guangdong
Province (S2011010001853) and Foundation for Distin-
guished Young Talents in Higher Education of Guang-
dong (LYM09101, LYM11090, LYM10099).
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