Self-assembly of Ge quantum dots on Si(100)-2×1 by pulsed laser deposition

Abstract

Self-assembled Ge quantum dots are grown on Si(100)-2×1 by pulsed laser deposition. The growth is studied by in situ reflection high-energy electron diffraction and postdeposition atomic force microscopy. After the completion of the wetting layer, transient hut clusters, faceted by different planes, are observed. When the height of these clusters exceeded a certain value, the facets developed into {305} planes. Some of these huts become {305}-faceted pyramids as the film mean thickness was increased. With further thickness increase, dome clusters developed on the expense of these pyramids.

Nanostenciling of Functional Materials by Room Temperature Pulsed Laser Deposition

“…2 where for the same number of 2000 pulses (repetition rate 10 Hz) the distance was increased from 4.5 to 7.5 cm. For different thicknesses of Ge films, the shape of the obtained structures is evolving, from a "dome-like" shape to a faceted "hut-type," once the thickness of the film decreases, in good agreement with the results recently reported in [38]. The possibility of varying the kinetic energy of the ejected atoms definitely makes the process interesting for the growth of Ge/Si structures and further study is warranted.…”

Nanosecond laser ablation and deposition of Ge films

“…Also shown are the morphology of a nano-sized droplet, and the cross section analysis gave a very small aspect ratio of <0.1. The morphology of nano-sized droplet resembled to those of the quantum dot grown by PLD using the same laser wavelength, reported elsewhere [5,6], but the growth mode is believed to be rather different in our case as the current deposition condition did not favor the Stranski-Krastanov growth. Furthermore, the droplets were detected on both Si and GaAs substrates.…”

“…The condensation of the high energetic species is capable of metastable material growth even at room temperature such as growing diamond-like carbon from graphite. For Ge, a range of amorphous to crystalline films have been deposited by pulsed laser deposition (PLD): amorphous Ge films which can be denser and less stressed than those by thermal evaporation [1], films which are denser, more homogeneous and stable than e-beam deposited films [2], films with optical and structural properties comparable to those deposited by magnetron sputtering [2,3], films that evolved in a similar homoepitaxial growth as in molecular beam epitaxy when deposited at low laser fluence [4], and also Ge quantum dot on Si via Stranski-Krastanov growth [5,6].…”

STM study of pulsed laser assisted growth of Ge quantum dot on Si(1 0 0)-(2 × 1)

“…We have studied the effects of pulsed laser induced electronic excitations on the self-assembly of Ge QD on Si(1 0 0)-(2 × 1) grown by pulsed laser deposition (PLD) [9,10]. Here we expand the scope of our previous observations with reflection high-energy electron diffraction (RHEED) by conducting an ultrahigh vacuum scanning tunneling microscopy (STM) study of the laser excitation effect on deposition at different laser energy densities.…”