Title :
Total Dose Response of Ge MOS Capacitors With HfO2/Dy 2O3 Gate Stacks
Author :
Chen, D.K. ; Schrimpf, R.D. ; Fleetwood, D.M. ; Galloway, K.F. ; Pantelides, S.T. ; Dimoulas, A. ; Mavrou, G. ; Sotiropoulos, A. ; Panayiotatos, Y.
Author_Institution :
Vanderbilt Univ., Nashville
Abstract :
We report the results of total ionizing dose radiation tests on germanium-substrate MOS capacitors with HfO2/Dy2O3 gate dielectrics with effective oxide thicknesses of ~1.9 and 1.1 nm. There are significant densities of border traps before irradiation, and no measurable changes in device response after 10 Mrad(SiO2) exposure. We attribute the lack of net oxide charge trapping to equal electron and hole trapping and/or charge neutralization via gate leakage current. The introduction of Dy2O3 evidently leads to reduced charge trapping in these HfO2/Dy2O3 dielectrics relative to devices with only HfO2.
Keywords :
MOS capacitors; X-ray effects; dielectric materials; dysprosium compounds; electron traps; elemental semiconductors; germanium; hafnium compounds; hole traps; leakage currents; Ge-HfO2-Dy2O3 - Interface; MOS capacitors; border trap densities; charge neutralization; effective oxide thicknesses; electron trapping; gate dielectrics; hole trapping; ionizing dose radiation tests; leakage current; oxide charge trapping; radiation absorbed dose 10 Mrad; Charge carrier processes; Density measurement; Dielectric devices; Dielectric measurements; Electron traps; Hafnium oxide; Ionizing radiation; Leakage current; MOS capacitors; Testing; Border traps; HfO$_{2}$ ; dysprosium; germanium MOS capacitors; high-K dielectric; total dose radiation effects; ultrathin gate oxide;
Journal_Title :
Nuclear Science, IEEE Transactions on
DOI :
10.1109/TNS.2007.892116
