TY  - JOUR
AU  - Rieger, Torsten
AU  - Jörres, Torsten
AU  - Vogel, J.
AU  - Biermanns, A.
AU  - Pietsch, U.
AU  - Grützmacher, Detlev
AU  - Lepsa, Mihail Ion
TI  - Crystallization of $HfO_2$ in $InAs/HfO_2$ core–shell nanowires
JO  - Nanotechnology
VL  - 25
IS  - 40
SN  - 1361-6528
CY  - Bristol
PB  - IOP Publ.
M1  - FZJ-2014-04991
SP  - 405701
PY  - 2014
AB  - We report the impact of deposition parameters on the structure of HfO2 covering InAs nanowires (NWs) being potential candidates for future field-effect transistors (FETs). Molecular beam epitaxial-grown Au-free InAs NWs were covered with HfO2 deposited by atomic-layer deposition. The impact of the film thickness as well as the deposition temperature on the occurrence and amount of crystalline HfO2 regions was investigated by high-resolution transmission electron microscopy (TEM) and x-ray diffraction. Compared to the deposition on planar Si substrates, the formation probability of crystalline HfO2 on InAs NWs is significantly enhanced. Here, even 3 nm thick films deposited at 250 °C are partly crystalline. Similarly, a low deposition temperature of 125 °C does not result in completely amorphous 10 nm thick HfO2 films, they contain monoclinic as well as orthorhombic HfO2 nanocrystals. Combining HfO2 and Al2O3 into a laminate structure is capable of suppressing the formation of crystalline HfO2 grains.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000342503800007
DO  - DOI:10.1088/0957-4484/25/40/405701
UR  - https://juser.fz-juelich.de/record/156128
ER  -