Title :
SILC decay in Ge-based MOS devices with La2O3 gate dielectrics subjected to constant voltage stress
Author :
Evangelou, E.K. ; Rahman, M.S. ; Androulidakis, I.I. ; Dimoulas, A. ; Mavrou, G. ; Galata, S.
Author_Institution :
Dept. of Phys., Univ. of Ioannina, Ioannina, Greece
Abstract :
The effect of constant voltage stress on Pt/La2O3/n-Ge MOS devices biased at accumulation is investigated and reported. It is found that the stress induced leakage current (SILC) initially increases due to electron charge trapping on pre-existing bulk oxide defects. After 10 s approximately, a clear decay of SILC commences which follows a t-n power law, with n lying between 0.56 and 0.75. This decay of SILC is not changed or reversed when the stressing voltage stops for short time intervals. The effect is attributed to the creation of new positively charged defects in the oxide because of the applied stressing voltage, while other mechanisms proposed in the past are proved insufficient to explain the experimental data.
Keywords :
MIS devices; dielectric materials; electron traps; elemental semiconductors; germanium; lanthanum compounds; leakage currents; platinum; MOS devices; Pt-La2O3-Ge; SILC decay; bulk oxide defects; constant voltage stress; electron charge trapping; gate dielectrics; positively charged defects; stress-induced leakage current; time 10 s; Current measurement; Dielectric constant; Dielectric devices; Dielectric materials; Electron traps; Leakage current; MOS devices; MOSFETs; Stress; Voltage;
Conference_Titel :
Solid State Device Research Conference, 2009. ESSDERC '09. Proceedings of the European
Conference_Location :
Athens
Print_ISBN :
978-1-4244-4351-2
Electronic_ISBN :
1930-8876
DOI :
10.1109/ESSDERC.2009.5331319