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1.
Y. He J. Ramdani N. A. El-Masry D. C. Look S. M. Bedair 《Journal of Electronic Materials》1993,22(12):1481-1485
Low-temperature (LT) growth of In0.47Ga0.53P was carried out in the temperature range from 200 to 260°C by gas source molecular beam epitaxy using solid Ga and In and
precracked PH3. The Hall measurements of the as-grown film showed a resistivity of ∼106 Ω-cm at room temperature whereas the annealed film (at 600°C for 1 h) had at least three orders of magnitude higher resistivity.
The Hall measurements, also, indicated activation energies of ∼0.5 and 0.8 eV for the asgrown and annealed samples, respectively.
Double-crystal x-ray diffraction showed that the LT-InGaP films had ∼47% In composition. The angular separation, Δθ, between
the GaAs substrate and the as-grown LT-InGaP film on (004) reflection was increased by 20 arc-s after annealing. In order
to better understand the annealing effect, a LT-InGaP film was grown on an InGaP film grown at 480°C. While annealing did
not have any effect on the HT-InGaP peak position, the LT-InGaP peak was shifted toward the HT-InGaP peak, indicating a decrease
in the LT-InGaP lattice parameter. Cross-sectional transmission electron microscopy indicates the presence of phase separation
in LT-InGaP films, manifested in the form of a “precipitate-like” microstructure. The analytical scanning transmission electron
microscopy analysis of the LT-InGaP film revealed a group-V nonstoichiometric deviation of ∼0.5 at.% P. To our knowledge,
this is the first report about the growth and characterization of LT-InGaP films. 相似文献
2.
W. Tong T. Yang W. Park M. Chaichimansour S. Schön B. K. Wagner C. J. Summers 《Journal of Electronic Materials》1997,26(6):728-731
SrS:Ce thin films have been grown by gas source molecular beam epitaxy (GSMBE). The growth conditions have been systematically
investigated as a function of growth temperature, sulfur to strontium flux ratio, and cerium flux. Single crystal SrS and
high quality SrS:Ce were successfully grown on GaAs and glass substrates, respectively, without post-annealing process at
temperature as low as 600°C. It was found that the electroluminescence (EL) performance was greatly improved by addition of
ZnS during the growth. 相似文献
3.
We report on the electrical characteristics of the two-dimensional electron gas (2DEG) formed in an InAlAs/InAsxP1-x/InP pseudomorphic composite-channel modulation-doped (MD) structure grown by solid source (arsenic and phosphorus) molecular
beam epitaxy (SSMBE). The As composition, x, of strained InAsxP1-x was determined by x-ray diffraction analysis of InP/InAsxP1-x/InP multi-quantum wells (MQWs) with compositions of x=0.14 to x=0.72. As the As composition increases, the room temperature
sheet resistance of InAlAs/InAsxP1-x/InP composite-channel MD structures grown over a range of As compositions decreased from 510 to 250 Ω/cm2, resulting from the greater 2DEG confinement and lower electron effective mass in the InAsxP1-x channel as x increases. The influence of growth conditions and epitaxial layer designs on the 2DEG mobility and concentration
were investigated using 300 K and 77 K Hall measurements. As the exposure time of the As4 flux on the growth front of InAsxP1-x increased during growth interruptions, the 2DEG mobility, in particular the 77K mobility, was considerably degraded due to
increased roughness at the InAlAs/InAsxP1-x interface. For the InAlAs/InAs0.6P0.4/InP composite-channel MD structure with a spacer thickness of 8 nm, the room temperature 2DEG mobility and density were 7200
cm2/Vs and 2.5 × 1012 cm−2, respectively. These results show the great potential of the InAlAs/InAsxP1-x/InP pseudomorphic composite-channel MD heterostructure for high frequency, power device applications. 相似文献
4.
J. W. Huang J. M. Ryan K. L. Bray T. F. Kuech 《Journal of Electronic Materials》1995,24(11):1539-1546
The defect engineering in metalorganic vapor phase epitaxy InxGa1-xAs and InP by controlled oxygen doping using diethyl aluminum ethoxide (DEALO) was developed in this study. DEALO doping has
led to the incorporation of Al and O, and the compensation of shallow Si donors in InxGa1−xAs: Si with 0 ≤ x ≤ 0.25. With the same DEALO mole fraction during growth, the incorporation of Al and O was found to be independent
of x, but the compensation of Si donors decreases with increasing In content. Deep level transient spectroscopy analysis on
a series of InxGa1-xAs: Si. samples with 0 ≤ x ≤ 0.18 revealed that oxygen incorporation led to a set of deep levels, similar to those found in
DEALO doped GaAs. As the In composition was increased, one or more of these deep levels became resonant with the conduction
band and led to a high electron concentration in oxygen doped In0.53Ga0.47As. Low temperature photoluminescence emission measurements at 12K on the same set of samples revealed the quenching of the
near-band edge peak, and the appearance of new oxygen-induced emission features. DEALO doping in InP has also led to the incorporation
of Al and O, and the compensation of Si donors due to oxygen-induced multiple deep levels. 相似文献
5.
S. H. Li P. K. Bhattacharya S. W. Chung J. X. Zhou E. Gulari 《Journal of Electronic Materials》1993,22(4):409-412
Solid boron and antimony doping of silicon and SiGe grown by molecular beam epitaxy using disilane and germane as sources
has been studied. Elemental boron is a well behaved p-type dopant. At effusion cell temperatures of 1700–1750°C, hole carrier
concentrations in the 1020 cm−3 range have been obtained. Elemental antimony doping shows surface segregation problems. For uniformly doped layers, the as-grown
materials do not show n-type conductivity. Electron concentrations in the 1017 cm−3 range were obtained by post-growth conventional and rapid thermal annealing at 900 and 1000°C, respectively. The electron
Hall mobility improves with optimum annealing time. Delta doping of buried layers exhibits slightly better incorporation behavior
including significant surface riding effects. 相似文献
6.
A simple growth model has been successfully developed for the determination of the As to P incorporation ratio, i.e., mole
fraction y, in growing GaxIn1−xAsyP1−y quaternary alloys by gas source molecular beam epitaxy. The model covers the whole composition range with only two fitting
parameters, kIn and kGa, whose physical meanings are the product of As to P desorption time constant ratio and incorporation rate constant ratio
for InAsyP1−y and GaAsyP1−y, respectively. The best fitting values of kIn and kGa from our experimental results are 28 and 3, respectively, at a growth temperature of 480°C. The temperature dependency of
the parameters were also studied. The activation energies of kIn and kGa are +30 and −330 meV, respectively. The significant differences between the parameters may be due to the different bond energies
of binary alloys. 相似文献
7.
We have studied the growth of (lll)B-oriented AlAs/GaAs/AIAs double barrier resonant tunneling structures in a gas source
molecular beam epitaxy system. We investigate the current peak-to-valley ratios of the resonant tunneling structures grown
on (lll)B GaAs substrates under the various growth conditions, such as III/V flux ratios, substrate temperature, growth interruption
at the heterointerfaces, buffer or contact layers, etc. We demonstrate that, in contrast to previous reports, high quality
heterostructures can be grown in a gas source system if certainIII/V flux ratio, substrate temperature, and misoriented substrate are used. We show that the As/Ga flux ratio plays the key role
for the growth on the misoriented ( 111 )B GaAs substrate, and growth at extremely high temperatures is not beneficial to
the negative differential resistance. We also show that, although inserting a growth interruption in the buffer layer is believed
to be helpful to the surface morphology, it is detrimental to the current peak-to-valley ratio. 相似文献
8.
9.
C. A. Coronado E. Ho P. A. Fisher J. L. House K. Lu G. S. Petrich L. A. Kolodziejski 《Journal of Electronic Materials》1994,23(3):269-273
The use of gas source molecular beam epitaxy, using hydrogen selenide and elemental Zn as source materials, has resulted in
the growth of high quality ZnSe on closely lattice-matched GaAs and (In,Ga)P. The undoped ZnSe epilayers are comparable in
quality to material grown by molecular beam epitaxy, as indicated by narrow double-crystal x-ray diffraction rocking curves
and intense photoluminescence dominated by a single donor-bound near-bandedge excitonic feature. Nitrogen species, derived
from a radio frequency plasma source, are successfully used as acceptor impurities for ZnSe; photoluminescence spectra confirm
the incorporation of nitrogen by the presence of the expected donor-to-acceptor pair recombination. Atomic concentrations
of nitrogen as high as 5 x 1018 cm-3, are measured by secondary ion mass spectroscopy. Thus far, capacitance-voltage measurements indicate net acceptor concentrations
(NA -ND) of approximately 1017 cm-3. 相似文献
10.
报道了InAs/GaSb超晶格中波材料的分子束外廷生长技术研究.通过改变GaSb衬底上分子束外延InAs/GaSb超晶格材料的衬底温度,以及界面的优化等,改善超晶格材料的表面形貌和晶格失配,获得了晶格失配△a/a=1.5×10-4,原子级平整表面的InAs/GaSb超晶格材料,材料77 K截止波长为4.87 μm. 相似文献
11.
P. Savolainen M. Toivonen S. Orsila M. Saarinen P. Melanen V. Vilokkinen M. Dumitrescu T. Panarello M. Pessa 《Journal of Electronic Materials》1999,28(8):980-985
AlxGayIn1−x−yAs/InP strained-layer multiple-quantum-well lasers emitting at 1.3 μm have been grown by solid source molecular beam epitaxy,
and the performance characteristics have been studied. The lasers contain 4, 5, or 6 compressively strained quantum wells
in the active region. They exhibit low transparency current densities, high gain coefficients, and high characteristic temperatures
compared to conventional GaInAsP/InP quantum well lasers. The results show that desired lasing features can be achieved with
relatively simple layer structures if the doping profiles and waveguide structures are properly designed and the material
is grown to high structural perfection. 相似文献
12.
In this paper, we report the effect of using a group-V residual source evacuation (RSE) time on the interfaces of InGaAs/lnGaAsP
quantum wells (QWs) grown by gas-source molecular beam epitaxy. High-resolution x-ray rocking curve and low-temperature photoluminescence
(PL) were used to characterize the material quality. By optimizing the RSE time, a PL line width at 15K as narrow as 6.6 meV
is observed from a 2 nm wide single QW, which is as good as or better than what has been reported for this material system.
Very sharp and distinct satellite peaks as well as Pendellosung fringes are observed in the x-ray rocking curves of InxGa1−xAs/InxGa1−xASyP1−y multiple QWs, indicating good crystalline quality, lateral uniformity, and vertical periodicity. Theoretical considerations
of the PL linewidths of InxGa1−xAs/InxGa1−xASyP1−y single QWs show that for QW structures grown with the optimized RSE time, the PL linewidth is mainly due to alloy scattering,
whereas the contribution from interface roughness is small, indicating a good interface control. 相似文献
13.
In this paper we show that pseudomorphically strained heterostructures of InAs
x
P1−x
/InP may be an alternative to lattice-matched heterostructures of In1−x
Ga
x
As
y
P1−y
/InP for optoelectronic applications. We first studied the group-V composition control in the gas-source molecular beam epitaxy
(GSMBE) of the GaAs1-x
P
x
/GaAs system. Then we studied GSMBE of strained InAs
x
P1−x
/InP multiple quantum wells with the ternary well layer in the composition range 0.15 <x < 0.75. Structural and optical properties were characterized by high-resolution x-ray rocking curves, transmission electron
microscopy, absorption and low-temperature photoluminescence measurements. High-quality multiple-quantum-well structures were
obtained even for highly strained (up to 2.5%) samples. The achievement of sharp excitonic absorptions at 1.06, 1.3 and 1.55μm at room temperature from InAs
x
P1−x
/InP quantum wells suggests the possibility of long-wavelength optoelectronic applications. 相似文献
14.
A. Mircea R. Azoulay L. Dugrand R. Mellet K. Rao M. Sacilotti 《Journal of Electronic Materials》1984,13(3):603-620
We present a procedure for the MOVPE of InP as simple as the one currently used for GaAs. InP and InGaAsP alloys are grown
on InP substrates using trimethy1indium (TMI), phosphine, trimethylgallium (TMG) and arsine. The choice of carrier gas is
important ; a mixture of hydrogen and nitrogen allowed us to grow uniform layers over large areas at atmospheric pressure,
without pyrolizing the phosphine or separating the input reactants. Preliminary characterization results are presented.
Most information contained in this paper was presented at the 1983 Electron Materials Conference as paper Cl. 相似文献
15.
Guan-Ru Chen Hao-Hsiung Lin Jyh-Shyang Wang Ding-Kang Shih 《Journal of Electronic Materials》2003,32(4):244-248
Optical properties of InAs1−xNx/In0.53Ga0.47As (hereafter, abbreviated as InAsN/InGaAs) single quantum wells (SQWs) grown on InP substrates by gas source molecular-beam
epitaxy are studied using photoluminescence (PL) measurements. By comparing the low-temperature PL spectra of InAs/InGaAs
and InAsN/InGaAs SQWs, InAs and InAsN phases are found to coexist in the InAsN layer. Such serious alloy inhomogeneities result
in obvious exciton localization by potential irregularities. The blue shift of the PL peak after rapid thermal annealing (RTA)
is found to originate mainly from As-N interdiffusion inside the well layer. According to the temperature-dependent PL results,
uniformity of the InAsN layer can be effectively improved by RTA, and the exciton localization is, thus, relieved. Comparison
of luminescence quenching and excitation-power-dependent PL behavior between the QWs with and without nitrogen content suggests
that the quality of the QW is degraded by the introduction of nitrogen, and the degradation can only be partially recovered
by post-growth RTA. 相似文献
16.
The organometallic vapor phase epitaxial (OM-VPE) growth of AlxGa1-xPyAs1-y on graded GaPyAs1-yGaAs in the compositional range 0 < x < 0.9 and 0 < y < 0.6 is reported. It is found that composition control can be easily
achieved, and that the vapor phase ratio of trimethylaluminum to trimethylgallium strongly influences the incorporation of
P in the solid. A model is developed which explains this in terms of competing reaction rates. The model gives a good fit
to the experimental data. 相似文献
17.
We have studied the properties of molecular beam epitaxially (MBE)-grown Erdoped III-V semiconductors for optoelectronic applications.
Optically excited Er3+ in insulating materials exhibits optical emission chiefly around 1.54 μm, in the range of minimum loss in silica fiber. It
was thought, therefore, that an electrically pumped Er-doped semiconductor laser would find great applicability in fiber-optic
communication systems. Exhaustive photoluminescence (PL) characterization was conducted on several of As-based III-V semiconductors
doped with Er, on bulk as well as quantum-well structures. We did not observe any Errelated PL emission at 1.54 μm for any
of the materials/structures studied, a phenomenon which renders impractical the realization of an Er-doped III-V semiconductor
laser. Deep level transient spectroscopy studies were performed on GaAs and AlGaAs co-doped with Er and Si to investigate
the presence of any Er-related deep levels. The lack of band-edge luminescence in the GaAs:Er films led us to perform carrier-lifetime
measurements by electro-optic sampling of photoconductive transients generated in these films. We discovered lifetimes in
the picosecond regime, tunable by varying the Er concentration in the films. We also found the films to be highly resistive,
the resistivity increasing with increasing Er-concentration. Intensive structural characterization (double-crys-tal x-ray
and transmission electron microscopy) performed by us on GaAs:Er epilayers indicates the presence of high-density nanometer-sized
ErAs precipitates in MBE-grown GaAs:Er. These metallic nanoprecipitates probably form internal Schottky barriers within the
GaAs matrix, which give rise to Shockley-Read-Hall recombination centers, thus accounting for both the high resistivities
and the ultrashort carrier lifetimes. Optoelectronic devices fabricated included novel tunable (in terms of speed and responsivity)
high-speed metal-semiconductor-metal (MSM) photodiodes made with GaAs:Er. Pseudomorphic AlGaAs/ InGaAs modulation doped field
effect transistors (MODFETs) (for high-speed MSM-FET monolithically integrated optical photoreceivers) were also fabricated
using a GaAs:Er buffer layer which substantially reduced backgating effects in these devices. 相似文献
18.
Brett Z. Nosho John A. Roth John E. Jensen Le Pham 《Journal of Electronic Materials》2005,34(6):779-785
The fabrication of high-quality focal plane arrays from HgCdTe layers grown by molecular beam epitaxy (MBE) requires a high
degree of lateral uniformity in material properties such as the alloy composition, doping concentration, and defect density.
While it is well known that MBE source flux nonuniformity can lead to radial compositional variation for rotating substrates,
we have also found that composition can be affected significantly by lateral variations in substrate temperature during growth.
In diagnostic experiments, we systematically varied the substrate temperature during MBE and quantified the dependence of
HgCdTe alloy composition on substrate temperature. Based on these results, we developed a methodology to quickly and nondestructively
characterize MBE-grown layers using postgrowth spatial mapping of the cutoff wavelength from the Fourier transform infrared
(FTIR) transmission at 300 K, and we were able to obtain a quantitative relationship between the measured spatial variations
in cutoff and the substrate temperature lateral distribution during growth. We refined this methodology by more directly inferring
the substrate temperature distribution from secondary ion mass spectroscopy (SIMS) measurements of the As concentration across
a wafer, using the fact that the As incorporation rate in MBE-grown p-type layers is highly sensitive to substrate temperature.
Combining this multiple-point SIMS analysis with FTIR spatial mapping, we demonstrate how the relative contributions from
flux nonuniformity and temperature variations on the lateral composition uniformity can be separated. This capability to accurately
map the lateral variations in the substrate temperature has been valuable in optimizing the mounting and bonding of large
substrates for MBE growth, and can also be valuable for other aspects of MBE process development. 相似文献
19.
M. Zandian J. M. Arias J. Bajaj J. G. Pasko L. O. Bubulac R. E. Dewames 《Journal of Electronic Materials》1995,24(9):1207-1210
Characterization of defects in Hg1−xCdxTe compound semiconductor is essential to reduce intrinsic and the growth-induced extended defects which adversely affect
the performance of devices fabricated in this material system. It is shown here that particulates at the substrate surface
act as sites where void defects nucleate during Hg1−xCdxTe epitaxial growth by molecular beam epitaxy. In this study, we have investigated the effect of substrate surface preparation
on formation of void defects and established a one-to-one correlation. A wafer cleaning procedure was developed to reduce
the density of such defects to values below 200 cm−2. Focal plane arrays fabricated on low void density materials grown using this new substrate etching and cleaning procedure
were found to have pixel operability above 98.0%. 相似文献
20.
M. Daraselia G. Brill J. W. Garland V. Nathan S. Sivananthan 《Journal of Electronic Materials》2000,29(6):742-747
In this work in-situ spectroscopic ellipsometry (SE) has been applied for the simultaneous determination of the growth temperature
and alloy composition for the epitaxial Cd1−xZnxTe(211)/Si(211) structure. The optical dielectric functions of CdTe and Cd0.96Zn0.04Te (CZT) epilayers were studied as a function of temperature both ex-situ and in-situ in the range from 1.6 eV to 4.5 eV.
We employed parametric models for the simulation of the optical properties of CZT at and between the critical points (CP)
E0, E0 + Δ0, E1, E1 + Δ1, E2(Σ) and E2(Σ). Critical point energies and line widths for Cd1−xZnxTe were obtained through the fitting process, which included both zero order and higher order derivatives of the SE pseudo
dielectric function. The dependence of the different critical points on Zn concentration x is discussed. It has been demonstrated
that the energy of the weak E0 + Δ0 transition can be used to measure composition, while the E1 energy can be used as a real-time temperature measure. The model parameters were optimized through the simultaneous analysis
of multiple data sets, and the temperature dependent model was developed for in-situ application. Our analysis is estimated
to produce uncertainties of only ±0.5°C in measuring the temperature and ±0.5% in measuring the composition of only the zero
order dielectric function is being fitted. The effects of a surface overlayer, of reflected beam deflections, and of other
experimental problems on the overall accuracy, are discussed as well as ways to improve the in-situ SE data quality. 相似文献