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1.
The growth rates of CdTe and HgCdTe by hot wall metalorganic vapor phase epitaxy were studied as functions of growth temperatures
and partial pressures of precursors. It is suggested that the growth of CdTe and HgCdTe was controlled by reaction kinetics.
The relationship between growth processes and epilayer properties was discussed and high quality epilayers were obtained. 相似文献
2.
Shizuo Fujita Tsuyoshi Tojyo Tetsu Yoshizawa Shigeo Fujita 《Journal of Electronic Materials》1995,24(3):137-141
Post-growth thermal annealing (e.g., 500°C, 30 min), is proposed as one of the promising techniques to realize and to improve
the quality of p-type ZnSe layers grown by metalorganic vapor phase epitaxy (MOVPE). The layers were grown at low temperature
(350°C) by photo-assisted MOVPE with doping nitrogen from tertiarybutylamine (t-BuNH2). The flow rate of t-BuNH2 was limited to be relatively low, in order to avoid heavy doping, with which as-grown layers exhibited electrically high-resistivity;
but the thermal annealing converted the layers to p-type. As the as-grown layers exhibited the stronger donor-to-acceptor
pair recombination lines or the weaker donor-bound excitonic emission (Ix) lines in photoluminescence, the annealed layers resulted in higher net acceptor concentration, which was 1 x 1017 cm−4 at the optimum conditions at present. 相似文献
3.
The growth rates of GaSb by metalorganic vapor phase epitaxy were studied as functions of growth temperatures and partial
pressures of precursors. A Langmuir-Hinshelwood model was used to explain the GaSb growth rate in the chemical reaction controlled
regime. The relationship between growth kinetics and epilayer qualities was discussed and properties of GaSb were obtained. 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.
The growth of nominally undoped GaSb layers by atmospheric pressure metalorganic vapor phase epitaxy on GaSb and GaAs substrates
is studied. Trimethylgallium and trimethylantimony are used as precursors for the growth at 600°C in a horizontal reactor.
The effect of carrier gas flow, V/III-ratio, and trimethylgallium partial pressure on surface morphology, electrical properties
and photoluminescence is investigated. The optimum values for the growth parameters are established. The carrier gas flow
is shown to have a significant effect on the surface morphology. The optimum growth rate is found to be 3–8 μm/ h, which is
higher than previously reported. The 2.5 μm thick GaSb layers on GaAs are p-type, having at optimized growth conditions room-temperature
hole mobility and hole concentration of 800 cm2 V−1 s−1 and 3·1016 cm-3, respectively. The homoepitaxial GaSb layer grown with the same parameters has mirror-like surface and the photoluminescence
spectrum is dominated by strong excitonic lines. 相似文献
6.
The growth and characterization of strained GaInAs and GaInAsP multiquantum well (MQW) laser structures has been investigated. The use of triple axis x-ray diffraction (XRD), in addition to the conventional high resolution double crystal XRD, yields further information about the structural integrity of these complex structures. Buried heterostructure lasers with eight GaInAsP wells (+1.0% strain, 80Å thick) exhibit a record low threshold current of 3.1 mA. By using a constant As/P ratio in the wells and barriers of an MQW laser structure, we have shown that the structure can be annealed at 700°C for 1 h with only a minimal shift (-4 nm) in the photoluminescence emission wavelength. Conventional lattice-matched GaInAs/GaInAsP MQW structures exhibit a shift of-46 nm under the same conditions. 相似文献
7.
K. Yasuda K. Mori Y. Kubota K. Kojima F. Inukai Y. Asai T. Nimura 《Journal of Electronic Materials》1998,27(8):948-953
Growth characteristics of (100)-oriented CdZnTe layers grown by atmospheric-pressure metalorganic vapor phase epitaxy have
been studied using dimethylzinc (DMZn), dimethylcadmium (DMCd), diethyltelluride (DETe), and dimethyltelluride (DMTe) as precursors.
Variations of Zn composition and layer growth rate were examined by changing the DMZn supply ratio, defined as DMZn/(DMCd+DMZn),
where the precursors are expressed in appropriate units of flow rate, from 0 (no DMZn) to 1.0 (no DMCd), while keeping the
total group II supply rate constant. The growth rate of CdZnTe layers was found to decrease monotonically with increase of
the DMZn supply ratio. On the other hand, the Zn composition x of grown layers increased gradually up to x=0.04 with increase
of the DMZn supply ratio from 0 to 0.8, beyond which the Zn composition increased abruptly to ZnTe. The abrupt transition
of Zn composition was suppressed by increasing the VI/II ratio. The growth mechanism of CdZnTe layers was studied based on
the observed growth characteristics of CdTe and ZnTe. A higher desorption rate from the growth surface for Zn species than
for Cd species, and a higher rate of CdTe formation than ZnTe formation are believed to cause the observed growth characteristics.
CdZnTe layers with high crystal quality were grown in a wide range of Zn compositions. The full-width at half-maximum values
for x-ray double-crystal rocking-curve measurements were lower than 320 arc-sec for x<0.3 and x>0.75. 相似文献
8.
Jun Hu Hongyuan Wei Shaoyan Yang Chengming Li Huijie Li Xianglin Liu Lianshan Wang Zhanguo Wang 《半导体学报》2019,40(10):85-94
Due to the remarkable growth rate compared to another growth methods for gallium nitride(GaN)growth,hydride vapor phase epitaxy(HVPE)is now the only method for mass product GaN substrates.In this review,commercial HVPE systems and the GaN crystals grown by them are demonstrated.This article also illustrates some innovative attempts to develop homebuilt HVPE systems.Finally,the prospects for the further development of HVPE for GaN crystal growth in the future are also discussed. 相似文献
9.
A combined thermodynamic-kinetic approach to the epitaxial deposition of InGaAsP alloys on GaAs substrates is presented. Good
agreement with experimental group V solid phase incorporation has been found when neglecting the 2V2 = V4 (V = As,P) vapor phase reactions, while the group III solid phase composition is well described by simple mass-transport
limited processes. InGaAsP materials, lattice matched to GaAs, have been grown in a wide composition range toward the ternary
limit [In(0.49)Ga(0.51)P]. Furthermore, high quality InGaAsP/GaAs strained quantum wells with a bandgap below that of GaAs
are realized for the first time. 相似文献
10.
P. Mitra F. C. Case H. L. Glass V. M. Speziale J. P. Flint S. P. Tobin P. W. Norton 《Journal of Electronic Materials》2001,30(6):779-784
We report the growth of HgCdTe on (552)B CdZnTe by metalorganic vapor phase epitaxy (MOVPE). The (552) plane is obtained by
180 rotation of the (211) plane about the [111] twist axis. Both are 19.47 degrees from (111), but in opposite directions.
HgCdTe grown on the (552)B-oriented CdZnTe has a growth rate similar to the (211)B, but the surface morphology is very different.
The (552)B films exhibit no void defects, but do exhibit ∼40 μm size hillocks at densities of 10–50 cm−2. The hillocks, however, are significantly flatter and shorter than those observed on (100) metalorganic vapor phase epitaxy
(MOVPE) HgCdTe films. For a 12–14 μm thick film the height of the highest point on the hillock is less than 0.75 μm. No twinning
was observed by back-reflection Laue x-ray diffraction for (552)B HgCdTe films and the x-ray double crystal rocking curve
widths are comparable to those obtained on (211)B films grown side-by-side and with similar alloy composition. Etch pit density
(EPD) measurements show EPD values in the range of (0.6–5)×105 cm−2, again very similar to those currently observed in (211)B MOVPE HgCdTe. The transport properties and ease of dopant incorporation
and activation are all comparable to those obtained in (211)B HgCdTe. Mid-wave infrared (MWIR) photodiode detector arrays
were fabricated on (552)B HgCdTe films grown in the P-n-N device configuration (upper case denotes layers with wider bandgaps).
Radiometric characterization at T=120–160 K show that the detectors have classical spectral response with a cutoff wavelength
of 5.22 μm at 120 K, quantum efficiency ∼78%, and diffusion current is the dominant dark current mechanism near zero bias
voltage. Overall, the results suggest that (552)B may be the preferred orientation for MOVPE growth of HgCdTe on CdZnTe to
achieve improved operability in focal plane arrays. 相似文献
11.
Yi-Keng Fu Yu-Hsuan Lu Ren-Hao Jiang Bo-Chun ChenYen-Hsiang Fang Rong Xuan Yan-Kuin SuChia-Feng Lin Jebb-Fang Chen 《Solid-state electronics》2011,62(1):142-145
Near ultraviolet light-emitting diodes (LEDs) with quaternary AlInGaN quantum barriers (QBs) are grown by atmospheric pressure metalorganic vapor phase epitaxy. The indium mole fraction of AlInGaN QB could be enhanced as we increased the TMG flow rate. Both the wavelength shift in EL spectra and forward voltage at 20 mA current injection were reduced by using AlInGaN QB. Under 100 mA current injection, the LED output power with Al0.089In0.035Ga0.876N QB can be enhanced by 15.9%, compared to LED with GaN QB. It should be attributed to a reduction of lattice mismatch induced polarization mismatch in the active layer. 相似文献
12.
G. P. Yablonskii A. L. Gurskii E. V. Lutsenko I. P. Marko B. Schineller A. Guttzeit O. Schön M. Heuken K. Heime R. Beccard D. Schmitz H. Juergensen 《Journal of Electronic Materials》1998,27(4):222-228
Photoluminescence (PL) and reflection spectra of undoped and Mg-doped GaN single layers grown on sapphire substrates by metalorganic
vapor phase epitaxy (MOVPE) were investigated in a wide range of temperatures, excitation intensities, and doping levels.
The undoped layers show n-type conductivity (μ=400 cm2/Vs, n=3×1017 cm−3). After annealing at T=600–700°C, the Mg-doped layers showed p-type conductivity determined by the potential-profiling technique.
A small value of the full width at half maximum (FWHM=2.8 meV) of the excitonic emission and a high ratio between excitonic
and deep level emission (≈5300) are evidences of the high layer quality. Two donor centers with activation energies of 35
and 22 meV were observed in undoped layers. A fine structure of the PL band with two narrow lines in the spectral range of
the donor-acceptor pair (DAP) recombination was found in undoped layers. An anomaly was established in the temperature behavior
of two groups of PL lines in the acceptor-bound exciton and in donor-acceptor pair regions in Mg doped layers. The lower energy
line quenched with increasing temperature appreciably faster than the high energy ones. Our data does not agree with the DAP
recombination model. It suggests that new approaches are required to explain the recombination mechanisms in undoped and Mg-doped
GaN epitaxial layers. 相似文献
13.
The complete crystallographic orientation dependence of the growth rate for GaAs low pressure organometallic vapor phase epitaxy
(LPOMVPE) is determined using a previously described semi-empirical model. A set of LPOMVPE growth rate polar diagrams is
presented for reactor temperatures near 550°C as well as near 700°C. Also, the variation of the growth rate polar diagrams
as a function of process variables is given. The experimental data utilized in the semiempirical model was attained using
a typical horizontal reactor LPOMVPE system and typical LPOMVPE process parameters. 相似文献
14.
Low pressure metalorganic vapor phase epitaxy grown strained InGaAs/GaAs quantum well structures have been characterized by
photoluminescence and x-ray diffraction. It is shown that beyond the pseudomorphic limit, these structures show considerable
gallium/indium interdiffusion at the interfaces and partial strain relaxation in the quantum well layers. 相似文献
15.
C. Pelosi G. Attolini C. Bocchi P. Franzosi C. Frigeri M. Berti A. V. Drigo F. Romanato 《Journal of Electronic Materials》1995,24(11):1723-1730
GaAs epitaxial layers have been grown on (001) 6† off-oriented toward (110) Ge substrates by metalorganic vapor phase epitaxy.
In order to study the influence of V/III ratio on the growth mechanisms and the structural properties of the layers, the input
flow of arsine was changed over a wide range of values, while keeping constant all other experimental settings. Optical microscopy
in the Nomarski contrast mode, x-ray topography and high resolution diffractometry, transmission electron microscopy and Rutherford
backscattering have been used to investigate the epilayers. It has been found that the growth rate increases and the surface
morphology worsens with increasing V/III ratio. The abruptness of the layer-substrate interface has also been found to strongly
depend on the V/III ratio, the best results being obtained under Ga-rich conditions. The main structural defects within the
layers are stacking faults and misfit dislocations. Layers grown under As-rich conditions only contain stacking faults, probably
originated by a growth island coalescence mechanism, whereas layers grown under Ga-rich conditions contain both misfit dislocations
and stacking faults generated by dissociation of threading segments of interfacial dislocations. In spite of the different
defects, the strain relaxation has been found to follow the same trend irrespective of the V/III ratio. Finally, the relaxation
has been found to start at a thickness exceeding the theoretical critical value. 相似文献
16.
B. K. Han L. Li M. J. Kappers R. F. Hicks H. Yoon M. S. Goorsky K. T. Higa 《Journal of Electronic Materials》1998,27(2):81-84
Thin films of InxGa1−xAs (0<x<0.012) on GaAs (001) were grown by metalorganic vapor phase epitaxy using triisopropylindium, triisobutylgallium,
and tertiarybutylarsine. The effect of the process conditions, temperature, and V/III ratio on the film quality was studied
using high resolution x-ray diffraction, scanning tunneling microscopy, and Hall measurements. High quality films were grown
at temperatures as low as 475 °C and at a V/III ratio of 100. However, under these conditions, a change in growth mode from
step flow to two-dimensional nucleation was observed. 相似文献
17.
Shizuo Fujita Takeharu Asano Kensaku Maehara Shigeo Fujita 《Journal of Electronic Materials》1994,23(3):263-268
Doping characteristics of nitrogen in ZnSe using photo-assisted vapor phase epitaxy were investigated. The source precursors
and the doping source were diethylzinc, dimethylselenide, and tertiarybutylamine. Photoluminescence, electrical properties
of Schottky diodes, and electroluminescence from homo and double heterojunction diodes consistently supported p-type behavior
of the ZnSe:N layers. At the conditions investigated, higher doping was achieved at lower substrate temperature and irradiation
intensity; e.g., 350°C and 45 mW/ cm2, respectively. As a guideline, net acceptor concentration was estimated as 2 x 1017 cm-3 for the ZnSe:N layer with nitrogen concentration of 5 x 1017 cm-3 revealed by secondary ion mass spectroscopy. 相似文献
18.
J. Söllner J. Schmoranzer H. Hamadeh B. Bollig E. Kubalek M. Heuken 《Journal of Electronic Materials》1995,24(11):1557-1561
ZnMgSSe heterostructures have been grown in a low-pressure metalorganic vapor phase epitaxy system with the precursors dimethylzinc
triethylamine, ditertiarybutylselenide, tertiarybutylthiol, and biscyclopentadienylmagnesium at 330°C and a total pressure
of 400 hPa. The optimization of the single layers was carried out by means of low temperature photoluminescence. Only the
near band edge emission was observable with negligible deep levels. The heterostructures consisting of a triple ZnSe quantum
well showed intense luminescence which hints at an effective carrier confinement. Scanning transmission electron microscopy
investigations of the heterostructures still showed structural detects since the layers were not lattice matched to the GaAs
substrate yet. 相似文献
19.
H. Kanber S. X. Bar P. E. Norris C. Beckham M. Pacer 《Journal of Electronic Materials》1994,23(2):159-166
GaAs MESFET device structures have been grown on silicon nitride or silicon dioxide masked 50 and 76 mm GaAs substrates by
low pressure organometallic vapor phase epitaxy. Very smooth, featureless morphology and 100 percent selectivity of GaAs islands
have been achieved over a range of growth conditions. Optimization of the GaAs p-buffer of the field effect transistor structure
has led to improved device performance, including increased breakdown voltage. Device characteristics of the 0.5 μm gate low
noise metal semiconductor field-effect transistors fabricated on these islands show good performance and wafer to wafer reproducibility
on the second device lot. 相似文献
20.
The focus of this paper is the integrated use of system and wafer monitors to obtain a complete picture of the growth process
and to identify the major causes of variance. In situ monitoring of a growing layer of Hg1-xCdxTe using laser reflectometry has been compared with the outputs of various system monitors such as pyrometer, organometallic
concentration, and flow. Differences between the expected and measured concentrations were corrected by initially adjusting
the organometallic flows, and the remaining variance in CdTe interdiffused multilayer process layer thickness was then corrected
by increasing the CdTe cycle time. The remainder of the layer gave a homogenized alloy composition of 0.256 for a target value
of 0.258. This example shows how different in situ monitors have been integrated to give a comprehensive picture of the growth
process, which were then related to known kinetic behavior. As a result of this monitoring, it was possible to identify critical
parameters for control. 相似文献