TY  - JOUR
KW  - Defects
KW  -  In-Situ
KW  -  Nanowires
KW  -  STEM
KW  -  TEM
PB  - AMER CHEMICAL SOC
N2  - The droplet consumption step in self-catalyzed III?V semiconductor nanowires can produce material that contains a high density of line defects. Interestingly, these defects are often associated with twin boundaries and have null Burgers vector, i.e., no long-range strain field. Here, we analyze their stability by considering the forces that act on them and use in situ aberration corrected scanning transmission electron microscopy (STEM) to observe their behavior in GaAsP nanowires (NWs) using short annealing cycles. Their movement appears to be consistent with the thermally activated single- or double-kink mechanisms of dislocation glide, with velocities that do not exceed 1 nm s?1. We find that motion of individual defects depends on their size, position, and surrounding environment and set an upper limit to activation energy around 2 eV. The majority of defects (>70%) are removed by our postgrowth annealing for several seconds at temperatures in excess of 640 °C, suggesting that in situ annealing during growth at lower temperatures would significantly improve material quality. The remaining defects do not move at all and are thermodynamically stable in the nanowire.
ID  - discovery10080694
Y1  - 2019/07/10/
AV  - public
EP  - 4580
TI  - Defect Dynamics in Self-Catalyzed III-V Semiconductor Nanowires
A1  - Gott, JA
A1  - Beanland, R
A1  - Fonseka, HA
A1  - Peters, JJP
A1  - Zhang, Y
A1  - Liu, H
A1  - Sanchez, AM
JF  - Nano Letters
UR  - https://doi.org/10.1021/acs.nanolett.9b01508
SN  - 1530-6992
IS  - 7
N1  - This version is the author accepted manuscript. For information on re-use, please refer to the publisher?s terms and conditions.
SP  - 4574
VL  - 19
ER  -