Laser Stimulated Growth of Epitaxial Gaas

1982 ◽  
Vol 17 ◽  
Author(s):  
Walter Roth ◽  
Herbert Kräutle ◽  
Annemarie Krings ◽  
Heinz Beneking
Keyword(s):  
Growth Rate ◽  
Substrate Temperature ◽  
Epitaxial Layers ◽  
Yag Laser ◽  
Single Crystalline ◽  
Epitaxial Gaas ◽  
Temperature Range ◽  
Mocvd Reactor ◽  
Gaas Substrates

ABSTRACTStimulated growth of single crystalline GaAs has been obtained by irradiation of (100) oriented GaAs substrates inside an MOCVD reactor with a pulsed Nd-YAG laser.Process temperatures have been varied between 540°C and 360°C. In the non-irradiated areas, below 480°C substrate temperature the growth rate decreases rapidly, whereas in the irradiated part of the substrate epitaxial layers could be grown in the whole temperature range investigated. Below 450°C, the growth is reaction limited.

Quantitative In Situ Growth Measurements of Chlorine-Activated Homoepitaxial Diamond Cvd

1994 ◽  
Vol 349 ◽  
Author(s):  
Chenyu Pan ◽  
John L. Margrave ◽  
Robert H. Hauge
Keyword(s):  
Growth Rate ◽  
Substrate Temperature ◽  
Growth Rates ◽  
Diamond Growth ◽  
Flow Rates ◽  
Temperature Range ◽  
Quantitative Studies ◽  
Growth Activation ◽  
Lower Temperature

ABSTRACTIn situ quantitative studies of the effects of substrate temperature, methane and chlorine flow rates on homoepitaxial diamond growth rates on (110) surfaces in a chlorine-activated diamond CVD reactor have been carried out using a Fizeau interferometer. The temperature dependence of diamond growth rates was found to display three distinct growth activation energies, ranging from 9±2 kcal/mol in the substrate temperature of 750-950°C, to 3.2±0.2 kcal/mol in the temperature range of 300-650°C, followed by 1.2±0.2 kcal/mol in the temperature range of 102-250°C. Atomic hydrogen is believed to be the dominant activating species in the highest temperature range, and atomic chlorine is believed to be the dominant species in the lower temperature regions. Studies of the methane flow effect on diamond growth rates revealed a linearity, indicating that the diamond growth rate was of the first order in methane flows. Diamond growth rates were also found to increase linearly with the chlorine flow. At high chlorine flow rates, however, an accelerated diamond growth rate was observed. Discussion is given to explain the observed results.

Growth by the CSVT (close-spaced vapor transport) technique and characterization of epitaxial GaAs layers on Ge substrates

1991 ◽  
Vol 69 (3-4) ◽  
pp. 390-406 ◽  
Author(s):  
E. Koskiahde ◽  
D. Cossement ◽  
N. Guelton ◽  
R. Fillit ◽  
R. G. Saint-Jacques ◽  
...  
Keyword(s):  
Growth Rate ◽  
Water Vapor ◽  
Epitaxial Layer ◽  
Transport Model ◽  
Vapor Transport ◽  
Epitaxial Layers ◽  
Gaas Substrates ◽  
Pole Figures ◽  
Gaas Films ◽  
Crystallographic Orientations

Epitaxial layers of GaAs on (100) GaAs substrates can be grown by close-spaced vapor transport using water vapor as the transporting agent. The parameters for the transport are [Formula: see text], ΔT′ = 45 °C, and δ = 0.03 cm (where [Formula: see text] is the temperature of the graphite heating the substrate; ΔT′, the temperature difference between the graphite heating the source and the one heating the substrate; and δ, the thickness of the spacer separating the GaAs source and the substrate). Mirrorlike epitaxial layers of GaAs are obtained with these parameters when water vapor, at a partial pressure of 4.58 Torr (1 Torr = 133.3 Pa), is introduced with H2 at the beginning of the temperature rise of the reactor. The dimensions of the epitaxial layer are only limited by the size of the reactor. Using the same growth conditions, it is not possible to obtain mirrorlike films of GaAs on (100) Ge substrates. Instead, the layers are dull grey (sample no. 1). It is however not a polycrystalline deposition since the pole figures, obtained by X-ray diffraction, reveal only four crystallographic orientations; {100} the main one, {221} the secondary one, and {021} + {112} two minor contributions. Mirrorlike films of GaAs on (100) Ge substrates of less than 1 cm2 have been obtained with [Formula: see text], ΔT′ = 25 °C, and δ = 0.03 cm. With these conditions, the growth rate is 0.25 ± 0.08 μm min−1. The time evolution of [Formula: see text] and ΔT′, from room temperature up to the equilibrium temperature also influences the surface morphology of GaAs films on Ge while this was not the case for GaAs films on GaAs substrates. When the Ge substrate is larger than 1 cm2, the centre of the film becomes textured but the edges remain mirrorlike (sample no. 2). Pole figures obtained for the center and the edges of sample no. 2 are similar. They are characterized by one large diffraction due to the {100} orientation. A few random crystallographic orientations and sometimes the {221} orientation, however, bearly emerge from the background of these pole figures. Also transmission electron microscopy does not reveal any major difference between the center and the edges of sample no. 2. The density of threading dislocations is the same for both regions, varying from 108 cm−2, close (2–3 μm) to the interface, to 107 cm−2 in the thickness of the film. No misfit dislocations were observed. Antiphase boundaries are present in both regions as well. The only difference between the centre and the edges of sample no. 2 involves microtwin bundles: in the center region, there are two microtwin bundles per micrometre of interface, extending up to 6 μm in the GaAs film while on the edges, there is one bundle per micrometre with an extension of only one micrometre into the epitaxial layer. Mirrorlike GaAs films can be obtained on (100) Ge substrates of at least 1 in (1 in = 2.5 cm) in diameter by increasing δ to 0.2 cm and by injecting water vapor in the reactor only when [Formula: see text] reached 650 °C; the other deposition parameters remain the same as for sample no. 2. In these conditions, the growth rate of GaAs is 0.075 ± 0.020 μm min−1. By using a transport model based on thermodynamics, it is demonstrated that the flux intensity of GaAs transported from the source to the substrate, as well as the eventual presence of GeO as a nucleation site for GaAs on Ge, are both important for the morphology of the epitaxial layer.

Low Temperature Epitaxy of Hg1−xCdxTe

1988 ◽  
Vol 129 ◽  
Author(s):  
N. W. Cody ◽  
U. Sudarsan ◽  
R. Solanki
Keyword(s):  
Growth Rate ◽  
Electrical Properties ◽  
Low Temperature ◽  
Cadmium Telluride ◽  
Mercury Cadmium Telluride ◽  
Epitaxial Layers ◽  
High Quality ◽  
Temperature Range ◽  
Deposited Films ◽  
Low Temperature Epitaxy

ABSTRACTMercury cadmium telluride epitaxial layers have been grown using methylallyltelluride (MATe), dimethylcadmium (DMCd), and elemental Hg. Using these precursors high quality films have been achieved over the temperature range of 200-300°C. Comparisons are made between UV photon-assisted and thermally deposited films. Composition, growth rate, and electrical properties are compared for the two processes under various parameter conditions. Properties of films deposited on various substrates including CdTe, GaAs, and GaAs/Si are also described.

Diffusion model for deposition of epitaxial GaAs layers prepared by the MOCVD method

1991 ◽  
Vol 56 (10) ◽  
pp. 2020-2029
Author(s):  
Jindřich Leitner ◽  
Petr Voňka ◽  
Josef Stejskal ◽  
Přemysl Klíma ◽  
Rudolf Hladina
Keyword(s):  
Experimental Data ◽  
Growth Rate ◽  
Kinetic Model ◽  
Gas Phase ◽  
Substrate Surface ◽  
Deposition Process ◽  
Hydrogen Atmosphere ◽  
Epitaxial Gaas ◽  
Kinetics Of ◽  
Good Agreement

The authors proposed and treated quantitatively a kinetic model for deposition of epitaxial GaAs layers prepared by reaction of trimethylgallium with arsine in hydrogen atmosphere. The transport of gallium to the surface of the substrate is considered as the controlling process. The influence of the rate of chemical reactions in the gas phase and on the substrate surface on the kinetics of the deposition process is neglected. The calculated dependence of the growth rate of the layers on the conditions of the deposition is in a good agreement with experimental data in the temperature range from 600 to 800°C.

scholarly journals Properties and Mechanism of PEALD-In2O3 Thin Films Prepared by Different Precursor Reaction Energy

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 978
Author(s):  
Ming-Jie Zhao ◽  
Zhi-Xuan Zhang ◽  
Chia-Hsun Hsu ◽  
Xiao-Ying Zhang ◽  
Wan-Yu Wu ◽  
...  
Keyword(s):  
Growth Rate ◽  
Substrate Temperature ◽  
Film Growth ◽  
Atomic Layer ◽  
Amorphous Structure ◽  
Reaction Energy ◽  
Film Growth Rate ◽  
In2o3 Film ◽  
Intermediate Temperature Range ◽  
Layer Deposition

Indium oxide (In2O3) film has excellent optical and electrical properties, which makes it useful for a multitude of applications. The preparation of In2O3 film via atomic layer deposition (ALD) method remains an issue as most of the available In-precursors are inactive and thermally unstable. In this work, In2O3 film was prepared by ALD using a remote O2 plasma as oxidant, which provides highly reactive oxygen radicals, and hence significantly enhancing the film growth. The substrate temperature that determines the adsorption state on the substrate and reaction energy of the precursor was investigated. At low substrate temperature (100–150 °C), the ratio of chemically adsorbed precursors is low, leading to a low growth rate and amorphous structure of the films. An amorphous-to-crystalline transition was observed at 150–200 °C. An ALD window with self-limiting reaction and a reasonable film growth rate was observed in the intermediate temperature range of 225–275 °C. At high substrate temperature (300–350 °C), the film growth rate further increases due to the decomposition of the precursors. The resulting film exhibits a rough surface which consists of coarse grains and obvious grain boundaries. The growth mode and properties of the In2O3 films prepared by plasma-enhanced ALD can be efficiently tuned by varying the substrate temperature.

Very High Growth Rate of 4H-SiC Using MTS as Chloride-Based Precursor

2008 ◽  
Vol 600-603 ◽  
pp. 115-118 ◽  
Author(s):  
Henrik Pedersen ◽  
Stefano Leone ◽  
Anne Henry ◽  
Franziska Christine Beyer ◽  
Vanya Darakchieva ◽  
...  
Keyword(s):  
Growth Rate ◽  
Linear Dependence ◽  
Growth Rates ◽  
Molar Fraction ◽  
High Growth ◽  
High Growth Rate ◽  
Epitaxial Layers ◽  
Single Precursor ◽  
Very High

The chlorinated precursor methyltrichlorosilane (MTS), CH3SiCl3, has been used to grow epitaxial layers of 4H-SiC in a hot wall CVD reactor, with growth rates as high as 170 µm/h at 1600°C. Since MTS contains both silicon and carbon, with the C/Si ratio 1, MTS was used both as single precursor and mixed with silane or ethylene to study the effect of the C/Si and Cl/Si ratios on growth rate and doping of the epitaxial layers. When using only MTS as precursor, the growth rate showed a linear dependence on the MTS molar fraction in the reactor up to about 100 µm/h. The growth rate dropped for C/Si < 1 but was constant for C/Si > 1. Further, the growth rate decreased with lower Cl/Si ratio.

High resolution X-ray diffraction studies of CdxHg1-xTe/CdTe epitaxial layers grown by MOVPE on GaAs substrates

1990 ◽  
Vol 101 (1-4) ◽  
pp. 572-578 ◽  
Author(s):  
A.M. Keir ◽  
A. Graham ◽  
S.J. Barnett ◽  
J. Giess ◽  
M.G. Astles ◽  
...  
Keyword(s):  
High Resolution ◽  
Epitaxial Layers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gaas Substrates

InGaAsP Solid Solutions: Phase Diagrams, Growth from the Melt on GaAs Substrates, Elastically Strained Epitaxial Layers

2002 ◽  
pp. 67-79
Author(s):  
Yu. B. Bolkhovityanov ◽  
A. S. Yaroshevich ◽  
M. A. Revenko ◽  
E. M. Trukhanov
Keyword(s):  
Phase Diagrams ◽  
Solid Solutions ◽  
Epitaxial Layers ◽  
Gaas Substrates
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