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Metal Organic Vapor Phase Epitaxy (metal + organic_vapor_phase_epitaxy)

Distribution by Scientific Domains
Physics and Astronomy100%

Selected Abstracts

MOVPE growth and characterization of a -plane AlGaN over the entire composition range

PHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 7 2010
Masihhur R. Laskar
Abstract We report the metal organic vapor phase epitaxy (MOVPE) growth and characterization of non-polar (110) a -plane Alx Ga1,xN on (102) r -plane sapphire substrates over the entire composition range. Alx Ga1,xN samples with ,0.8 ,m thick layers and with x = 0, 0.18, 0.38, 0.46, 0.66, and 1.0 have been grown on r -plane sapphire substrates. The layer quality can be improved by using a 3-stage AlN nucleation layer and appropriate V/III ratio switching following nucleation. All a -plane AlGaN epilayers show an anisotropic in-plane mosaicity, strongly influenced by Al incorporation and growth conditions. Careful lattice parameter measurements show anisotropic in-plane strain that results in an orthorhombic distortion of the hexagonal unit cell, making Al composition determination from X-ray diffraction difficult. In general lower Al incorporation is seen in a -plane epilayers compared to c -plane samples grown under the same conditions. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Effective mass of InN estimated by Raman scattering

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7-8 2010
Jung Gon Kim
Abstract We have estimated the longitudinal effective mass (m,) of electron in n-type InN films by Raman scattering. The samples were grown by MOVPE (metal organic vapor phase epitaxy) with free carrier concentration of n =6.7×1018 -9.9×1018 cm -3 according to Hall measurement. A weak Raman signal observed at ,430 cm -1 at room temperature was sharpened and shifted to higher frequency toward the A1(TO)-phonon mode at 447 cm -1 with increasing n. This mode was assigned to the lower branch (L - ) of the longitudinal-optic-phonon-plasmon-coupled (LOPC) mode. The line shape was carefully analyzed by a semi-classical line-shape fitting analysis assuming deformation potential and electro-optic coupling mechanisms for the light scattering process. A line-shape fitting analysis was conducted by adjusting three major parameters; electron density, effective mass and plasmon damping rate. The analysis well reproduced values of electron density and mobility deduced by Hall measurement. Electron effective mass of m,*/m0 = 0.05 (±0.01) was also obtained as the best-fit parameter. The result agrees well with previous data obtained by other optical methods. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Direct MOVPE- and MBE-growth of a-plane GaN on r-plane sapphire

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2008
T. Aschenbrenner
Abstract We report on the growth of pit-free a-plane GaN on (102) sapphire (r-plane) substrates by metal organic vapor phase epitaxy (MOVPE) using a three step growth method without low temperature nucleation layer. X-ray diffraction , -scans of the symmetric GaN (11-20) reflex revealed for 1.2 ,m thick crack- and pit-free GaN layers low FWHM of 885 arcsec and 2484 arcsec measured by inclination in c- and m-direction, respectively. To analyze the evolution growth was stopped at different stages and the samples were measured with AFM, SEM, and XRD. Furthermore, we discuss the overgrowth of MOVPE GaN layer with molecular beam epitaxy (MBE). For smooth MOVPE templates with closed surfaces the morphology was reproduced, whereas for not coalesced thinner layers a different growth mode and a smoothening of the layers occurred. We will discuss SEM- and AFMdata in detail to examine this overgrowth procedure. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Cathodoluminescence properties of InGaN codoped with Zn and Si

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2006
Y. Honda
Abstract An InGaN alloy co-doped with Zn and Si was grown by metal organic vapor phase epitaxy on a GaN templated silicon substrate and the luminesence (CL) properties are studied by cathodoluminescence spectroscopy. As the result of co-doping of Zn and Si, the CL intensity was extremely enhanced; enhancement in the peak intensity as well as the full-width at half maximum. The optimum doping density was estimated to be N(Zn) = 4.0 x 1019/cm3 and N(Si) = 8.0 x 1018/cm3. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]