A study of the luminescence properties of epitaxial GaP containing atomic N grown by molecular beam epitaxy using NH3 and PH3 as the column V sources was conducted. The 77 K photoluminescence spectra of the N-doped epitaxial GaP showed a continuous redshift, from 5691 Å (2.18 eV) to 6600 Å (1.88 eV), resulted when the N concentration exceeded ∼5–7×1019 cm−3. This energy shift was found to be consistent with energy gap predictions using the dielectric theory of electronegativity for the GaP1−xNx system. The data also indicate that the emission intensity was maximum for N∼1×1020 cm−3, and then monotonically decreases with increasing N content. This is consistent with the formation of an indirect band-gap semiconductor.

Impurity-free selective layer disordering, utilizing Si3N4 masking stripes and SiO2 defect (vacancy) sources, is used to realize room-temperature continuous AlxGa1−xAs-GaAs quantum well heterostructure lasers.

Growth of the first few layers of an oxide mixture Ga 2 O 3 ͑Gd 2 O 3 ͒ on GaAs ͑100͒ substrate, electron-beam evaporated from a Ga 5 Go 3 O 12 source, was found to be a single crystal. Reflection high-energy electron diffraction and x-ray diffraction studies show that the thin oxide film is epitaxially grown on GaAs with the surface normal ͑110͒ and in-plane axis ͓001͔ parallel to ͑100͒ and ͓011͔ of GaAs, respectively, and has a structure isomorphic to Mn 2 O 3. Studies using high-resolution transmission electron microscopy on the oxide-GaAs interface indicate some atomic registry between the oxide and GaAs during the initial growth. The chemical composition of the oxide film was determined by x-ray photoelectron spectroscopy to be unequivocally pure Gd 2 O 3 .

Electron mobility, Hall scattering factor, and sheet conductivity in AlGaN/AlN/GaN heterostructures J. Appl. Phys. 110, 113713 (2011) Reduction of the potential energy barrier and resistance at wafer-bonded n-GaAs/n-GaAs interfaces by sulfur passivation J. Appl. Phys. 110, 104903 (2011) Diameter reduction of nanowire tunnel heterojunctions using in situ annealing Appl. Phys. Lett. 99, 203101 (2011) Substrate nitridation induced modulations in transport properties of wurtzite GaN/p-Si (100) heterojunctions grown by molecular beam epitaxy J. Appl. Phys. 110, 093718 (2011) Characteristics of a-GaN films and a-AlGaN/GaN heterojunctions prepared on r-sapphire by two-stage growth process

Articles you may be interested inEffect of low-temperature annealing on the electronic-and band-structures of (Ga,Mn)As epitaxial layers J. Appl. Phys. 115, 012009 (2014); 10.1063/1.4838036 Effect of low-temperature annealing on (Ga,Mn)As trilayer structures Appl. Phys. Lett. 82, 3020 (2003); 10.1063/1.1571666Effect of low-temperature annealing on transport and magnetism of diluted magnetic semiconductor (Ga, Mn)As Appl.Native defects in lowtemperature GaAs and the effect of hydrogenation

Carbon-doped GaAs with carbon concentrations ranging from 2~ 1Ol7 cmW3 to 2.6~ 102' cm -' has been characterized by variable temperature Hall effect measurements, secondary ion mass spectrometry (SIMS)) and double-crystal x-ray diffraction (DCXD). The samples studied were grown by metalorganic chemical vapor deposition (MOCVD) and by metalorganic molecular beam epitaxy (MOMBE). The hole mobility is dominated by degenerate conduction for hole concentrations > 1 X 1019 cma3, and the 77 K resistivity is typically 30%-35% lower than at 300 K in these samples. The mobilities of C-dopedp+-GaAs are found to be significantly higher than for Zn-or Be-doped p+-GaAs for doping concentrations in excess of 2x lo'* cmW3. The maximum achievable hole mobilities for C-doped material grown by the two techniques are nearly identical, indicating that neither MOCVD nor MOMBE has an inherent advantage over the other for producing low-resistivity p-type GaAs. SIMS analysis and Hall effect measurements reveal that the total carbon concentration, [Cl, is higher than the as-grown hole concentration, p, in the most heavily doped samples. DCXD measurements show general agreement with the lattice mismatch predicted by Vegard's law. However, for [C] > 102' cmm3 a discrepancy between the predicted and measured mismatch suggests that partial lattice relaxation or the presence of interstitial carbon may need to be considered in order to adequately describe the lattice contraction.

A comparison of the water vapor oxidation characteristics of AlAs, Al 0.98 Ga 0.02 As, and an Al x Ga 1Ϫx As digital alloy was performed. The Al x Ga 1Ϫx As digital alloy consists of periods of 49 monolayers of AlAs and 1 monolayer of GaAs and has an equivalent composition of xϭ0.98. Oxidation rates and the structural integrity of the three layers were compared. When oxidized in water vapor, the Al x Ga 1Ϫx As digital alloy and the AlAs have similar oxidation rates, both of which are twice as fast as the Al 0.98 Ga 0.02 As layer. Post-oxidation annealing of these samples at 450°C showed severe delamination at the oxide/GaAs interface in the AlAs sample while the Al x Ga 1Ϫx As digital alloy sample was not damaged.

In this study, the interface adhesion and mechanical strength of wafer bonded GaAs/GaAs and GaAs/InP semiconductors, each of (100) face, were characterized by combining the measurements of interface fracture energy γo and lap shear strength Es. The relations between the interface adhesion and annealing processes for four different types of bonding configurations, i.e., antiphase bonding, in-phase bonding, and twist bonding with 5° and 30° misalignments, were systematically studied. The surface free energy γα-GaAs/oxide (0.11–0.28 J/m2) of amorphous α-GaAs/oxide mixture was estimated based upon the reported surface free energy γc-GaAs (0.63 J/m2) of crystalline [100] GaAs and measured overall interface fracture energy γtotal (0.525 J/m2) of GaAs/GaAs bonded wafers. The micromorphologies of the bonded and debonded wafer interfaces were characterized by atomic force microscopy (AFM) and transmission electron microcopy (TEM). The interface microfailure mechanism of directly bonded GaAs wafers was proposed based on AFM and TEM microstructural analysis.