TY  - JOUR
AU  - Jansen, Marvin Marco
AU  - Perla, Pujitha
AU  - Kaladzhian, Mane
AU  - von den Driesch, Nils
AU  - Janssen, Johanna
AU  - Luysberg, Martina
AU  - Lepsa, Mihail I.
AU  - Grützmacher, Detlev
AU  - Pawlis, Alexander
TI  - Phase-Pure Wurtzite GaAs Nanowires Grown by Self-Catalyzed Selective Area Molecular Beam Epitaxy for Advanced Laser Devices and Quantum Disks
JO  - ACS applied nano materials
VL  - 3
IS  - 11
SN  - 2574-0970
CY  - Washington, DC
PB  - ACS Publications
M1  - FZJ-2020-05020
SP  - 11037 - 11047
PY  - 2020
AB  - The control of the crystal phase in self-catalyzed nanowires (NWs) is one of the central remaining open challenges in the research field of III/V semiconductor NWs. While several groups analyzed and revealed the growth dynamics, no experimental growth scheme has been verified yet, which reproducibly ensures the phase purity of binary self-catalyzed grown NWs. Here, we demonstrate the advanced control of self-catalyzed molecular beam epitaxy of GaAs NWs with up to a grade of 100% wurtzite (WZ) phase purity. The evolution of the most important properties during the growth, namely, the contact angle of the Ga droplet, the NW length, and the diameter is analyzed by scanning electron microscopy and transmission electron microscopy. Based on these results, we developed a comprehensive NW growth model for calculating the time-dependent evolution of the Ga droplet contact angle. Using this model, the Ga flux was dynamically modified during the growth to control and stabilize the contact angle in a certain range favoring the growth of phase-pure GaAs NWs. Although focusing on the self-catalyzed growth of WZ GaAs NWs, our model is also applicable to achieve phase-pure zinc blende (ZB) NWs and can be easily generalized to other III/V compounds. The self-catalyzed growth of such NWs may pave the way for substantial improvement of GaAs NW laser devices, the controlled growth of WZ/ZB quantum disks, and novel heterostructured core/multishell NW systems with a pristine crystalline order.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000595546500051
DO  - DOI:10.1021/acsanm.0c02241
UR  - https://juser.fz-juelich.de/record/888556
ER  -