@article{el-masry_behbehani_leboeuf_aumer_roberts_bedair_2001, title={Self-assembled AlInGaN quaternary superlattice structures}, volume={79}, ISSN={["0003-6951"]}, DOI={10.1063/1.1400763}, abstractNote={When an AlInGaN quaternary alloy is grown by metalorganic chemical-vapor deposition under certain growth conditions, a self-assembled superlattice structure is obtained. The superlattice structure is made of quaternary layers with different AIN and InN compositions. Transmission electron microscopy data show that the superlattice periodicity is regular with an individual layer thickness that depends on the growth conditions. Secondary ion mass spectrometry measurements show that the layers’ composition alternate between high-AIN and InN content and low-AlN and-InN content, while the in-plane lattice constant remains constant for both layers. A model is presented as a preliminary effort to explain these results.}, number={11}, journal={APPLIED PHYSICS LETTERS}, author={El-Masry, NA and Behbehani, MK and LeBoeuf, SF and Aumer, ME and Roberts, JC and Bedair, SM}, year={2001}, month={Sep}, pages={1616–1618} }
 @article{behbehani_piner_liu_el-masry_bedair_1999, title={Phase separation and ordering coexisting in InxGa1-xN grown by metal organic chemical vapor deposition}, volume={75}, ISSN={["0003-6951"]}, DOI={10.1063/1.124964}, abstractNote={We have recently reported the occurrence of phase separation in InxGa1−xN samples with x>0.25. Theoretical studies have suggested that InxGa1−xN can phase-separate asymmetrically into a low InN% phase and an ordered high InN% phase. In this letter, we report on the existence of simultaneous phase separation and ordering of InxGa1−xN samples with x>0.25. In these samples, phase separation was detected by both transmission electron microscopy selected area diffraction (TEM-SAD) and x-ray diffraction. Ordering was detected by both imaging and TEM-SAD.}, number={15}, journal={APPLIED PHYSICS LETTERS}, author={Behbehani, MK and Piner, EL and Liu, SX and El-Masry, NA and Bedair, SM}, year={1999}, month={Oct}, pages={2202–2204} }
 @article{piner_behbehani_elmasry_mcintosh_roberts_boutros_bedair_1997, title={Effect of hydrogen on the indium incorporation in InGaN epitaxial films}, volume={70}, ISSN={["0003-6951"]}, DOI={10.1063/1.118181}, abstractNote={The InN percent in metalorganic chemical vapor deposition (MOCVD) and atomic layer epitaxy (ALE) grown InGaN was found to be significantly influenced by the amount of hydrogen flowing into the reactor. The temperature ranges for this study are 710–780 °C for MOCVD, and 650–700 °C for ALE. For a given set of growth conditions, an increase of up to 25% InN in InGaN, as determined by x-ray diffraction, can be achieved by reducing the hydrogen flow from 100 to 0 sccm. Additionally, the hydrogen produced from the decomposition of ammonia does not seem to change the InN percent in the films, indicating that the ammonia decomposition rate is less than 0.1%. The phenomenon of having hydrogen control the indium incorporation was not reported in the growth of any other III–V compound previously studied.}, number={4}, journal={APPLIED PHYSICS LETTERS}, author={Piner, EL and Behbehani, MK and ElMasry, NA and McIntosh, FG and Roberts, JC and Boutros, KS and Bedair, SM}, year={1997}, month={Jan}, pages={461–463} }
 @article{mcintosh_piner_roberts_behbehani_aumer_elmasry_bedair_1997, title={Epitaxial deposition of GaInN and InN using the rotating susceptor ALE system}, volume={112}, ISSN={["0169-4332"]}, DOI={10.1016/S0169-4332(96)00992-0}, abstractNote={The growth of GaInN ternary alloys has been investigated using atomic layer epitaxy. Single crystal films have been deposited at 100 Torr in the 600°C to 700°C temperature range using the rotating susceptor approach. The InN percentage in the deposited films were found to depend on more than just the gas phase In/Ga ratio. In addition to the relative indium to gallium composition of the precursor gases, the indium incorporation was also found to depend on the absolute partial pressures of the reactant gases. The indium incorporation increases with decreasing growth temperatures, and may reach a temperature dependent saturation limit for a given set of growth conditions. Optimization of the ALE growth process has resulted in single crystal films exhibiting band edge room temperature photoluminescence for InN percentages of up to 27% in the GaInN ternary films. In addition, single crystal indium nitride has been grown using the ALE technique at 480°C.}, journal={APPLIED SURFACE SCIENCE}, author={McIntosh, FG and Piner, EL and Roberts, JC and Behbehani, MK and Aumer, ME and ElMasry, NA and Bedair, SM}, year={1997}, month={Mar}, pages={98–101} }
 @article{piner_behbehani_elmasry_roberts_mcintosh_bedair_1997, title={Impurity dependence on hydrogen and ammonia flow rates in InGaN bulk films}, volume={71}, ISSN={["0003-6951"]}, DOI={10.1063/1.119775}, abstractNote={H, C, and O impurity concentrations in metalorganic chemical vapor deposition grown InGaN were found to be dependent on the hydrogen and NH3 flow rates. By increasing the hydrogen flow rate from 0 to 100 sccm, a decrease of greater than two orders of magnitude in the C and O impurity levels and one order of magnitude in the H impurity level was observed. Increasing the NH3 flow rate from 1 to 5 slm results in a decrease in the C concentration and an increase in the H and O concentrations indicating that high purity NH3 (99.999%) can be a significant source of O contamination. Additional studies show that when the InN percent in the InGaN films increases, the impurity concentrations increase regardless of changes in the growth conditions. The InGaN films were grown from 710 to 780 °C and the impurity concentrations were characterized by secondary ion mass spectrometry.}, number={14}, journal={APPLIED PHYSICS LETTERS}, author={Piner, EL and Behbehani, MK and ElMasry, NA and Roberts, JC and McIntosh, FG and Bedair, SM}, year={1997}, month={Oct}, pages={2023–2025} }
 @article{joshkin_roberts_mcintosh_bedair_piner_behbehani_1997, title={Optical memory effect in GaN epitaxial films}, volume={71}, ISSN={["0003-6951"]}, DOI={10.1063/1.120414}, abstractNote={We report on memory effects in the optical properties of GaN and AlN epitaxial-films grown by atmospheric pressure metal organic chemical vapor deposition. After exposing selected areas of particular samples with He–Cd laser light (3.8 eV), we observed a persistent and marked decrease in the near band edge photoluminescence (PL) intensity emitted from these areas. This effect has been observed in epitaxial films that typically have a pyramidlike hillock surface. This ability to modulate PL emission intensity at individual points in these materials can be exploited as a method for optical data storage. A means of erasing information stored using this effect has also been investigated using lower energy (∼2 eV).}, number={2}, journal={APPLIED PHYSICS LETTERS}, author={Joshkin, VA and Roberts, JC and McIntosh, FG and Bedair, SM and Piner, EL and Behbehani, MK}, year={1997}, month={Jul}, pages={234–236} }