Control of InN quantum dot density using rare gases in metal organic vapor phase epitaxy

Abstract

Indium nitride (InN) quantum dots have been grown on gallium nitride (GaN) templates with heights of 10 and 20nm. The authors demonstrate that the surface densities of the dots are strongly affected by the nature of the carrier gas used during the growth, which can be used to modulate the surface density. The authors show here that replacing nitrogen by helium leads to a decrease of the dot surface density, while argon induces a strong increase of the density. Although validated for the InN∕GaN system, this approach has a more general scope and can be extended to other material systems.

MOVPE growth of InN buffer layers on sapphire

“…2. This observation of indium droplets was also reported for InN buffer layers grown with V/III molar ratios as high as 15,000, Further investigation both on V/III molar ratios and growth temperatures allowed to define two kinds of growth conditions to achieve InN buffer layers with similar crystalline quality as GaN buffer layers: either 17 nm InN grown at 450 1C with a V/III molar ratio of 5000 (sample A) in an argon ambient to enhance the InN nucleation [20], or 15 nm InN grown at 400 1C with a V/III molar ratio of 15,000 (sample B). In both cases, the buffer layers exhibited a FWHM of the rocking curve peak, assessed by GID measurements, of 3400 arcsec, to be compared to 3300 arcsec obtained on GaN buffer layers (Fig.…”

“…Samples of 10 nm thick InN buffer layers were grown at 450 1C on sapphire and nitrided sapphire with a V/III molar ratio of 5000. The sapphire nitridation was performed at 1070 1C for 5 min, using 2000 sccm NH 3 [20]. The improvement of the crystalline quality of the InN buffer layers was assessed by GID measurements, showing a decrease of the full-width at halfmaximum of the rocking curve peak from 9300 arcsec down to 5900 arcsec on nitrided sapphire.…”

High-Resolution Electron Microscopy of Semiconductor Heterostructures and Nanostructures

“…In the same year, Cao et al reported the growth of InN QDs and their shape and size dependence on the MBE deposition conditions [100]. After this, important improvements were achieved regarding smaller sizes and higher densities [101][102][103][104][105][106][107], and recently the emission, even very poor, of InN QDs [108,109] and growth and optical properties of cubic InN dots [110] have been reported. Other types of InN nanostructures fabricated so far include single [111] and multiple [112][113][114][115] quantum wells, nanocolumns [116,117], and nanowires [118][119][120].…”

Influence of the GaN spacer thickness on the structural and photoluminescence properties of multi-stack InN/GaN quantum dots

“…In order to increase the absorption of nanostructured solar cells, it is necessary to increase the volume of the nanostructure. In other words, the growth technique for high density QDs [4,5] or for the stacking the QD layers plays an important role in increasing the density of the dot volume. These findings motivate studying the structural and optical behaviors of the multi-stack InN/GaN QDs structure.…”