Influence of composition and substrate miscut on the evolution of (105)-terminated in-plane Si{sub 1−x}Ge{sub x} quantum wires on Si(001)

Journal Article · Tue Jul 01 04:00:00 EDT 2014 · APL Materials

DOI:https://doi.org/10.1063/1.4886218· OSTI ID:22304483

Watzinger, H.; Glaser, M.; Zhang, J. J.; Daruka, I.

Isolated in-plane wires on Si(001) are promising nanostructures for quantum transport applications. They can be fabricated in a catalyst-free process by thermal annealing of self-organized Si{sub 1−x}Ge{sub x} hut clusters. Here, we report on the influence of composition and small substrate miscuts on the unilateral wire growth during annealing at 570 °C. The addition of up to 20% of Si mainly affects the growth kinetics in the presence of energetically favorable sinks for diffusing Ge atoms, but does not significantly change the wire base width. For the investigated substrate miscuts of <0.12°, we find geometry-induced wire tapering, but no strong influence on the wire lengths. Miscuts <0.02° lead to almost perfect quantum wires terminated by virtually step-free (105) and (001) facets over lengths of several 100 nm. Generally, the investigated Si{sub 1−x}Ge{sub x} wires are metastable: Annealing at ≥600 °C under otherwise identical conditions leads to the well-known coexistence of Si{sub 1−x}Ge{sub x} pyramids and domes.

• OSTI ID: 22304483
• Journal Information: APL Materials, Journal Name: APL Materials Journal Issue: 7 Vol. 2; ISSN 2166-532X; ISSN AMPADS
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
ANNEALING
CATALYSTS
KINETICS
QUANTUM WIRES
SUBSTRATES