Abstract
The formation of self-assembled InAs quantum dots (QDs) on GaAs substrates has attracted much interest as a growth technique to fabricate promising nanoscale devices such as QD lasers [1] and QD infrared photodetectors [2,3] without an additional lithography process because QDs have discrete atom-like energy levels with good optical properties [4]. Self-assembled QDs in lattice-mismatched system,s such as InAs/GaAs and SiGe/Si, can be achieved by using the Stranski-Krastanov (SK) growth mode [5]. In the SK growth mode, the mismatched layer grows on the substrate two-dimensionally at first, then, above a critical thickness, strain-induced and dislocation-free QDs are formed on a residual two-dimensional wetting layer. An appropriate regulation of the respective growth conditions may provide the possibility for controlling precisely the size and the density of the QDs.
NSTL