Plasma-assisted Molecular Beam Epitaxy of High Optical Quality MgZnO Films on Zn-polar ZnO Substrates

2008 ◽  
Vol 1 ◽  
pp. 091202 ◽  
Author(s):  
Yoshio Nishimoto ◽  
Ken Nakahara ◽  
Daiju Takamizu ◽  
Atsushi Sasaki ◽  
Kentaro Tamura ◽  
...  
2008 ◽  
Vol 1068 ◽  
Author(s):  
Agam Prakash Vajpeyi ◽  
G. Tsiakatouras ◽  
A Adikimenakis ◽  
K. Tsagaraki ◽  
M Androulidaki ◽  
...  

ABSTRACTThe spontaneous growth of GaN nanopillars on (111) Si by plasma assisted molecular beam epitaxy has been investigated. The growth of GaN nanopillars on Si is driven by the lattice mismatch strain energy on Si and the high surface energy of the nitrogen stabilized (0001) GaN surface. A higher growth rate of nanopillars compared to a compact GaN film suggests the diffusion of Ga atoms from the uncovered substrate areas to the nucleated GaN nanopillars. The GaN nanopillars were characterized by field-emission scanning electron microscopy (FE-SEM), photoluminescence, and micro Raman spectroscopy. SEM image revealed that average diameter of GaN nanopillars was in the range of 70-100nm and an average height of 600nm. The photoluminescence (PL) spectra indicate the good emission property of the nanopillars. The low temperate PL spectrum exhibited an emission peak at 3.428eV besides a sharp excitonic peak. PL and Raman spectra indicate that GaN nanopillars are fully relaxed from lattice and thermal strain.


1983 ◽  
Vol 61 (2) ◽  
pp. 393-396 ◽  
Author(s):  
T. Fujii ◽  
S. Hiyamizu ◽  
O. Wada ◽  
T. Sugahara ◽  
S. Yamakoshi ◽  
...  

2002 ◽  
Vol 743 ◽  
Author(s):  
R. Armitage ◽  
Qing Yang ◽  
H. Feick ◽  
S. Y. Tzeng ◽  
J. Lim ◽  
...  

ABSTRACTSemi-insulating wurtzite GaN:C of high optical quality is obtained with CCl4or CS2 doping sources in plasma-assisted molecular-beam epitaxy in Ga-rich growth conditions. The highest resistivity (107Ω-cm) is found for [C] in the low 1018cm−3range. An increasing fraction of carbon appears to form electrically inactive pair defects for higher doping levels causing the concentration of uncompensated residual donors to be higher in films with [C] in the 1019cm−3range compared with [C] in the 1018cm−3range. Blue (2.9 eV) and yellow (2.2 eV) luminescence bands are associated with carbon-related defects, and additional support is provided for the association of the blue luminescence with the carbon-acceptor deactivating pair defect. Finally, the temperature dependence of the resistivity is described within the grain-boundary controlled transport model of Salzmanet al., Appl. Phys. Lett.76, 1431 (2000).


Photonics ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 215
Author(s):  
Rajeev R. Kosireddy ◽  
Stephen T. Schaefer ◽  
Marko S. Milosavljevic ◽  
Shane R. Johnson

Three InAsSbBi samples are grown by molecular beam epitaxy at 400 °C on GaSb substrates with three different offcuts: (100) on-axis, (100) offcut 1° toward [011], and (100) offcut 4° toward [011]. The samples are investigated using X-ray diffraction, Nomarski optical microscopy, atomic force microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The InAsSbBi layers are 210 nm thick, coherently strained, and show no observable defects. The substrate offcut is not observed to influence the structural and interface quality of the samples. Each sample exhibits small lateral variations in the Bi mole fraction, with the largest variation observed in the on-axis growth. Bismuth rich surface droplet features are observed on all samples. The surface droplets are isotropic on the on-axis sample and elongated along the [011¯] step edges on the 1° and 4° offcut samples. No significant change in optical quality with offcut angle is observed.


1991 ◽  
Vol 241 ◽  
Author(s):  
Y. Hwang ◽  
D. Zhang ◽  
T. Zhang ◽  
M. Mytych ◽  
R. M. Kolbas

ABSTRACTIn this work we demonstrate that photopumped quantum wellheterostructure lasers with excellent optical quality can be grown ontop of a LT GaAs buffer layer by molecular beam epitaxy. Hightemperature thermal annealing of these lasers blue-shifts the laseremission wavelengths but the presence/absence of a LT GaAs layerhad little effect on the overall laser thresholds. Also, to first order itwas not necessary to include an AlAs barrier layer to preventadverse effects (as has been necessary in the gate stack of MESFETs to prevent carrier compensation).


1982 ◽  
Vol 11 (2) ◽  
pp. 435-440 ◽  
Author(s):  
G. Wicks ◽  
C. E. C. Wood ◽  
H. Ohno ◽  
L. F. Eastman

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