TY  - JOUR
AU  - Rodenbücher, C.
AU  - Hildebrandt, E.
AU  - Szot, K.
AU  - Sharath, S. U.
AU  - Kurian, J.
AU  - Komissinskiy, P.
AU  - Breuer, Uwe
AU  - Waser, R.
AU  - Alff, L.
TI  - Hafnium carbide formation in oxygen deficient hafnium oxide thin films
JO  - Applied physics letters
VL  - 108
IS  - 25
SN  - 1077-3118
CY  - Melville, NY
PB  - American Inst. of Physics
M1  - FZJ-2016-03415
SP  - 252903 -
PY  - 2016
AB  - On highly oxygen deficient thin films of hafnium oxide (hafnia, HfO2− x) contaminated with adsorbates of carbon oxides, the formation of hafnium carbide (HfCx) at the surface during vacuum annealing at temperatures as low as 600 °C is reported. Using X-ray photoelectron spectroscopy the evolution of the HfCx surface layer related to a transformation from insulating into metallic state is monitored in situ. In contrast, for fully stoichiometric HfO2 thin films prepared and measured under identical conditions, the formation of HfCx was not detectable suggesting that the enhanced adsorption of carbon oxides on oxygen deficient films provides a carbon source for the carbide formation. This shows that a high concentration of oxygen vacancies in carbon contaminated hafnia lowers considerably the formation energy of hafnium carbide. Thus, the presence of a sufficient amount of residual carbon in resistive random access memory devices might lead to a similar carbide formation within the conducting filaments due to Joule heating.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000379039900026
DO  - DOI:10.1063/1.4954714
UR  - https://juser.fz-juelich.de/record/810832
ER  -