Self-assembled formation of vertical silicon-rich quantum wells and $\chem{Ge/SiGe}$ quantum wire superlattices

A. Beyer; E. Müller; C. David; B. Haas; B. Ketterer; D. Grützmacher

doi:doi:10.1209/epl/i2003-00536-9

DOI: 10.1209/epl/i2003-00536-9
Europhys. Lett., 63 (3) , pp. 459-464 (2003)

Self-assembled formation of vertical silicon-rich quantum wells and $\chem{Ge/SiGe}$ quantum wire superlattices

A. Beyer, E. Müller, C. David, B. Haas, B. Ketterer and D. Grützmacher

Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut CH-5232 Villigen, Switzerland

(Received 3 February 2003; accepted 2 June 2003)

Abstract
An original mechanism is described for the self-assembly of nanometer-sized structures in the silicon germanium material system. The self-organized formation of vertical $\chem{Si}$ -rich quantum wells (VSQW) is obtained during the growth of $\chem{Si}$ _1-x $\chem{Ge}$ _x on narrow line-shaped $\chem{Si}$ mesa, which are oriented in $\langle 150\rangle$ on the $\chem{Si}$ (001) surface. The occurrence of the VSQW is accompanied by the formation of {15 3 23} facets on top of the mesa. Detailed structural insights have been gathered by cross-sectional transmission electron microscopy, secondary electron microscopy and photoluminescence measurements. $\chem{Ge}$ quantum wires are embedded into the VSQW forming a superlattice containing $\chem{SiGe}$ and $\chem{Ge}$ wires. Intense low-temperature photoluminescence, which can be assigned to this one-dimensional superlattice, has been observed.

PACS
81.15.Hi - Molecular, atomic, ion, and chemical beam epitaxy.
68.65.-k - Low-dimensional, mesoscopic, and nanoscale systems: structure and nonelectronic properties.
78.67.Lt - Quantum wires.

© EDP Sciences 2003

Self-assembled formation of vertical silicon-rich quantum wells and quantum wire superlattices

Self-assembled formation of vertical silicon-rich quantum wells and $\chem{Ge/SiGe}$ quantum wire superlattices