TY - JOUR

T1 - Scale-Dependent Optimized Homoepitaxy of InAs(111)A

AU - Zelzer, Steffen

AU - Batabyal, Rajib

AU - Dardzinski, Derek

AU - Marom, Noa

AU - Grove-Rasmussen, Kasper

AU - Krogstrup, Peter

PY - 2022/8/30

Y1 - 2022/8/30

N2 - We combined in situ scanning tunneling microscopy (STM) with the conventional growth characterization methods of atomic force microscopy (AFM) and reflection high-energy electron diffraction (RHEED) to simultaneously assess atomic scale impurities and the larger scale surface morphology of molecular beam epitaxy (MBE) grown homoepitaxial InAs(111)A. By keeping a constant substrate temperature and indium flux while increasing the As2 flux, we find two differing MBE growth parameter regions for optimized surface roughness on the macroscale and the atomic scale. In particular, we show that a pure step flow regime with strong suppression of hillock formation can be achieved, even on substrates without intentional offcut. On the other hand, an indium adatom deficient surface with only a few remaining defects can be observed for a high density of hillocks. We identify the main remaining point defect on the latter surface by comparison to STM simulations. Furthermore, we provide a method for extracting root-mean-square surface roughness values and discuss their use for surface quality optimization by comparison to scale dependent, technologically relevant surface metrics. Finally, we map the separately optimized regions of the growth parameter space as a guide for future device engineering involving epitaxial InAs(111)A growth.

AB - We combined in situ scanning tunneling microscopy (STM) with the conventional growth characterization methods of atomic force microscopy (AFM) and reflection high-energy electron diffraction (RHEED) to simultaneously assess atomic scale impurities and the larger scale surface morphology of molecular beam epitaxy (MBE) grown homoepitaxial InAs(111)A. By keeping a constant substrate temperature and indium flux while increasing the As2 flux, we find two differing MBE growth parameter regions for optimized surface roughness on the macroscale and the atomic scale. In particular, we show that a pure step flow regime with strong suppression of hillock formation can be achieved, even on substrates without intentional offcut. On the other hand, an indium adatom deficient surface with only a few remaining defects can be observed for a high density of hillocks. We identify the main remaining point defect on the latter surface by comparison to STM simulations. Furthermore, we provide a method for extracting root-mean-square surface roughness values and discuss their use for surface quality optimization by comparison to scale dependent, technologically relevant surface metrics. Finally, we map the separately optimized regions of the growth parameter space as a guide for future device engineering involving epitaxial InAs(111)A growth.

KW - INITIO MOLECULAR-DYNAMICS

KW - TOTAL-ENERGY CALCULATIONS

KW - SURFACE

KW - TRANSITION

KW - SIMULATION

KW - GAAS(001)

KW - GROWTH

KW - OXIDE

KW - INAS

U2 - 10.1021/acs.cgd.2c00582

DO - 10.1021/acs.cgd.2c00582

M3 - Journal article

VL - 2022

SP - 5958

EP - 5965

JO - Crystal Growth & Design

JF - Crystal Growth & Design

SN - 1528-7483

IS - 22,10

ER -