摘要:

Thin Y-containing films have been deposited at 80 °C from aqueous solutions ofYNO3⋅5H2Oand urea on bare single crystal Si wafers, and on Si wafers coated with sulfonate-functionalized organic self-assembled monolayers. The as-deposited films are believed to be an amorphous yttrium basic carbonate and can be completely transformed at 600 °C in air to crystallineY2O3.Capacitance–voltage measurements on these films showed good dielectric properties, with a relative permitivity of 18, more than a factor of four higher than that ofSiO2.©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119679

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

The problem of adsorption desorption of methyl radicals on a surface with nanoscale curvature is numerically studied for typical chemical vapor deposition diamond growth conditions. Surface profiles with concave nanoscale curvature lead to an increase in the energy of adsorption, which can enhance the nucleation of the new phase on the substrates. Moreover, the nanoscale curvature is even able to provoke a nucleation of the new phase on substrates which do not have an affinity for nucleation. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119680

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Fully oriented AlCuCo decagonal quasicrystalline films on crystalline substrates were successfully prepared by multitarget magnetron sputtering followed by postannealing. The width of the rocking curve competes with that of a single crystal. To explain the result, we suggest that the full orientation of the films originates from the fact that only one atomic flat plane of the structure is available to match the flat surface of the substrate, which gives a minimum interface free energy. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119681

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Diffusion of zinc acceptors in InAsP by a metal-organic vapor-phase diffusion technique, whereby a low-pressure metal-organic vapor-phase epitaxy with dimethylzinc and phosphine is utilized as an open tube diffusion system, is demonstrated to accurately control the diffusion depth in the submicrometer range. The annealing effect on the zinc diffusion profiles in InAsP was found to be the activation of zinc acceptors similar to that in InP, but the maximum hole concentration of1×1019 cm−3for the zinc diffusion in InAsP was achieved. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119682

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

HeteroepitaxialY2O3films were grown on Si(100) substrates by the technique of reactive ionized cluster beam deposition. The crystallinity of the films was investigated with reflection high energy electron diffraction (RHEED), glancing angle x-ray diffraction (GXRD), and the interface was examined by high resolution transmission electron microscopy (HRTEM). Under the condition of 5 kV acceleration voltage at the substrate temperature of 800 °C, theY2O3film grows epitaxially on the Si(100) substrate. RHEED and GXRD results revealed that the epitaxial relationship betweenY2O3and Si(100) isY2O3(110)//Si(100), and HRTEM observation showed a sharp interface without an amorphous layer. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119683

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Compositional inhomogeneity in a GaInN ternary alloy layer is investigated. A theoretical estimation of the interaction parameter based on the delta lattice parameter suggests that the immiscibility of InN in a nitride alloy is very strong. We investigate the compositional splitting and the existence of InN inclusion in the GaInN epilayer grown on sapphire (0001) substrates. The mechanism of compositional inhomogeneity is discussed. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119684

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Successful growth of a cubicIn0.17Ga0.83N/GaNstructure exhibiting blue luminescence at temperatures up to 500 K is reported. Atomic force microscopy and x-ray diffraction are used to analyze the morphological and crystalline properties of the sample. Photoluminescence measurements reveal broad, but well defined emission with a maximum at 440–450 nm in the temperature range of 5–500 K. A line-shape analysis of the spectra, as well as measurements of the absorption coefficient, allow an estimation of the band-gap energy of the cubicIn0.17Ga0.83Nepilayer. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119685

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

The Schottky barrier heights ofAu/In1−xGaxAs1−yPycontacts have been determined as a function ofyby the capacitance–voltage and temperature dependent current–voltage characteristics measurements. The barrier height is observed to increase asyis increased for bothn- andp-type materials, with a more rapid increase for thep-type material. The compositional variation of the barrier heights forAu/n-In1−xGaxAs1−yPyis found to be identical to that of the conduction-band offsets inIn1−xGaxAs1−yPy/GaAsheterojunctions. A possible cause of this phenomenon is also discussed. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119686

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

We present a detailed study of the excitonic nonlinearities in InGaAs/GaAs multiple quantum wells based on both stationary and transient pump-and-probe transmission spectroscopy. Bleaching of the excitonic resonance and free carrier gain have been observed. A quantitative analysis of the observed nonlinearity is provided by means of a rigorous solution of the Bethe–Salpeter equation for the investigated heterostructures. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119687

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

We report on the observation of quantized conductance up to 10 K in epitaxially regrown, heterostructurally defined, 100-nm-wideGa0.25In0.75As/InPquantum wires. In addition to the plateaus at integer steps of2e2/h,we observe plateaus at0.2(2e2/h),0.7(2e2/h),and1.5(2e2/h),indicating spin polarization at zero magnetic field. Of these, the first two plateaus appear to evolve into one at around0.5(2e2/h)when the sample is subjected to a magnetic field parallel to the quantum wire. The observation of quantized conductance is made possible by the substantial improvement in the quality of the interface by regrowth. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119688

出版商:AIP    

年代:1997

数据来源: AIP