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The application of atomic-force-microscope (AFM) direct patterning to the selective positioning of InAs quantum dots (QDs) on a (100) GaAs substrate has been proposed and experimentally implemented. The AFM direct patterning was used to generate various patterns of several tens of nanometers in size, and InAs QDs were subsequently grown by a metalorganic chemical vapor deposition technique. A nonuniform distribution of the QDs was observed near the patterns. The detailed shape of the QD distribution and the size of the QDs depended on the geometrical properties such as the sidewall angle, the spacing, and the width of the patterns. We have been able to ascertain, through our work, what growth conditions are necessary for QDs’ alignment along the patterns.

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We report the selective growth of InAs self-assembled quantum dots ͑SAQDs͒ on silicon-dioxide/ silicon (SiO 2 /Si) substrates patterned in nanometer scale. The SiO 2 thin film is found to be an efficient mask material for prohibiting the growth of InAs SAQDs, while the formation of stable SAQDs is observed on the exposed surface of Si. We have utilized this selectivity to demonstrate almost one-dimensional alignment of InAs SAQDs on Si stripes. The crystallinity of SAQDs is also identified by high-resolution transmission electron microscope observation. Our study opens up a possibility of reliably integrating III-V quantum dot devices with conventional Si circuits.

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