A comparative study on MOVPE InN grown on Ga‐ and N‐polarity bulk GaN

Abstract

The influence of substrate polarity on the growth of InN film by MOVPE was investigated using bulk GaN as a substrate. Single-crystalline In-and N-polarity InN films were obtained on Ga-and N-polarity GaN substrate, respectively. Significant difference of the morphologies between the In-and N-polarity InN films was found. For the In-polarity InN film, the morphology was similar to that grown on sapphire substrate. The film surface was consisted of grains with small facets. In contrast, for the N-polarity InN film, the surface was consisted of large hexagonal shape crystal grains with flat surface. The grain size was about 2 µm in diameter on the average, and two-dimensional growth was enhanced obviously for each crystal grain. The influence of the growth temperature on the morphology, polarity, and optical property was also investigated.

Optical Properties of Uncapped InN Nanodots Grown at Various Temperatures

“…Note that even for InN nanodots grown at 725 C, the upper limit of our growth temperature, reasonably good optical properties can still be obtained. The 725 C-grown nanodots PL peak energy and FWHM of 0.75 eV and 74 meV, respectively, are comparable to typical results, 0.70 -0.83 eV and 100 -150 meV, for InN bulk films prepared by conventional MOVPE, which is generally performed at lower growth temperatures of 540 -650 C. [11][12][13] The preliminary results for these uncapped InN nanodots are encouraging. Although the linewidths (71-74 meV) are still large, they can already compete with those of the uncapped InAs and InGaAs surface quantum dots (54 -150 meV).…”

Phase separation of thick (∼1 µm) InxGa1−xN (x∼ 0.3) grown on AlN/Si(111): Simultaneous emergence of metallic In–Ga and GaN-rich InGaN

“…The corrugated surface feature of the sample is very similar to that for In-polar InN. 17) As shown in Fig. 3(b), many droplets were formed on the surface, and porous regions were formed in the interior of the film after the 90 min growth (60 min for the first growth and 30 min for the second growth).…”

Investigation of polarity dependent InN{0001} decomposition in N2 and H2 ambient

“…Wurtzite InN has two distinct planes along the c-axis: (0001) In-polarity and (000 1 ) N-polarity. To date, In-and N-polarity InN layers have been successfully grown using several methods such as molecular beam epitaxy (MBE) [4][5][6], metalorganic vapor phase epitaxy (MOVPE) [7,8], and hydride vapor phase epitaxy (HVPE) [9,10]. In addition, the polarity dependence of the thermal stability and decomposition reactions of InN layers in various ambients have been reported [11][12][13][14][15].…”