The Effect of Substrate Orientation on the Properties of (Ga, Al)As Grown by Gas Source Molecular Beam Epitaxy

1988 ◽  
Vol 144 ◽  
Author(s):  
A. Sandhu ◽  
T. FUJII ◽  
H. Ando ◽  
H. Ishikawa ◽  
E. Miyauchi
Keyword(s):  
Growth Rate ◽  
Growth Conditions ◽  
Group V ◽  
Group Iii ◽  
Al Content ◽  
Gas Source ◽  
Compensation Ratio ◽  
Potential Applications ◽  
Si Doped ◽  
Gas Source Mbe

ABSTRACTWe have carried out the first systemmatic investigation on the effect of substrate temperature and arsenic partial pressure on the morphology, growth rate, and compensation ratio of Si-doped GaAs, and the Al content of AlxGa1−xAs grown on just-cut (100), (110), (111)A&B, (311)A&B orientated GaAs substrates by gas source MBE (GSMBE). Triethylgallium ( TEG, Ga(C2H5)3 ) and triethylaluminium ( TEA, Al(C2H5)3 ) were used as group III sources, and solid arsenic ( As4 ) and silicon as a group V and IV sources, respectively. The best GaAs mophology was obtained at relatively high temperatures and arsenic pressures. The A orientations were identified as ‘fast surfaces,’ with the GaAs growth rate being comparable to the (100) orientation. The B orientations were identified as ‘slow surfaces,’ with the GaAs growth rate being much less (approximately 50% for the (111)B orientation ) than on the (100) orientation. The least compensated Si-doped GaAs was grown on the (311)A orientated substrate. The Al content, x, (nominally x=0.27 for (100)) of AlxGas1−xAs grown on (110), (111)A&B, was less than 0.05 and not affected by the growth conditions. The Al content of epilayers grown on (311)A&B ranged between x=0.1 to 0.27, strongly depending on the growth temperature.These results show that using GSMBE we can selectively modifying a large range of (Ga,Al)As crystal properties. Potential applications include the selective growth and realisation of ultra-fine and planar structures and devices.

Limitation of Selective Epitaxial Growth Conditions in Gas Source MBE Using Si2H6

1990 ◽  
Vol 204 ◽  
Author(s):  
Junro Sakai ◽  
Ken-Ichi Aketagawa ◽  
Toru Tatsumi
Keyword(s):  
Growth Rate ◽  
Epitaxial Growth ◽  
High Growth ◽  
Growth Conditions ◽  
High Growth Rate ◽  
Native Oxide ◽  
Initial Growth ◽  
Selective Epitaxial Growth ◽  
Gas Source ◽  
Gas Source Mbe

ABSTRACTLow temperature and high growth rate selective epitaxial growth (SEG) on Si02 patterned Si (001) substrate in gas-source molecular-beam epitaxy (GS-MBE) using pure Si2H6 has been investigated by RHEED observation. In the temperature range of 550 to 850°C, SEG was completely obtained at an initial growth stage. Limiting conditions of SEG were closely related with critical volume of supply gas that was equal to the total amount molecules supplied on SiO2 surface during the incubation period of initial growth. The surface SiO2 was induced to evaporate with Si2H6 supplied above 800°C, so that thermal cleaning temperature for removing native oxide came down to 800°C. As a result, the maximum process temperature of Si SEG now became 800°C, and its growth rate reached as high as 645A/min at growth temperature of 700°C.

In Situ Monitoring of the Smear-Out of the Ge Profile in GAS Source SiGe MBE Using Rheed Intensity Oscillations

1992 ◽  
Vol 263 ◽  
Author(s):  
K. Werner ◽  
S. Butzke ◽  
J.W. Maes ◽  
O.F.Z. Schannen ◽  
J. Trommel ◽  
...  
Keyword(s):  
Growth Rate ◽  
Molecular Beam ◽  
Surface Segregation ◽  
Catalytic Effect ◽  
Growth Conditions ◽  
In Situ Monitoring ◽  
Marked Contrast ◽  
Si Substrates ◽  
Gas Source

ABSTRACTWe have studied the deposition of GexSi1−x layers on (100) Si substrates by gas source molecular beam epitaxy (GSMBE) using disilane and germane.The investigation of RHEED intensity oscillations during growth reveals the well known rate enhancement obtained when adding a small amount of germane to the disilane flux. However, when exposing a previously deposited Ge layer to a pure disilane flux the growth rate during the first few monolayers remains at an enhanced value but returns to its homoepitaxial value after about 10 to 15 monolayers. This behaviour was observed under a variety of growth conditions. It is in marked contrast to the experience obtained in conventional Si/Ge MBE and suggests a catalytic effect of the particular surface present during GSMBE growth. We propose that this effect is caused by the surface segregation of Ge species and leads to a smear-out of the Ge profile in the layer.

Study of As and P Incorporation Behavior in GaAsP by Gas-Source Molecular-Beam Epitaxy

1991 ◽  
Vol 222 ◽  
Author(s):  
B. W. Liang ◽  
H. Q. Hou ◽  
C. W. Tu
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
High Energy ◽  
Ex Situ ◽  
Limited Growth ◽  
Group V ◽  
Group Iii ◽  
Gas Source ◽  
Simple Kinetic Model

ABSTRACTA simple kinetic model has been developed to explain the agreement between in situ and ex situ determination of phosphorus composition in GaAs1−xPx (x < 0.4) epilayers grown on GaAs (001) by gas-source molecular-beam epitaxy (GSMBE). The in situ determination is by monitoring the intensity oscillations of reflection high-energy-electron diffraction during group-V-limited growth, and the ex situ determination is by x-ray rocking curve measurement of GaAs1−xPx/GaAs strained-layer superlattices grown under group-III-limited growth condition.

scholarly journals Механизм роста монослоя на верхней грани Ga-каталитических нитевидных нанокристаллов GaAs и GaP

2022 ◽  
Vol 48 (4) ◽  
pp. 20
Author(s):  
А.А. Корякин ◽  
Ю.А. Еремеев ◽  
С.В. Федина ◽  
В.В. Федоров
Keyword(s):  
Growth Rate ◽  
Theoretical Model ◽  
Growth Mechanism ◽  
Growth Conditions ◽  
Nanowire Growth ◽  
Group V ◽  
Evaporation Coefficient ◽  
Catalyst Droplet ◽  
Monolayer Coverage

The growth mechanism of monolayer on the top facet of Ga-catalyzed GaAs and GaP nanowires is investigated. Within the framework of a theoretical model, the maximal monolayer coverage due to the material in the catalyst droplet, the nanowire growth rate and the content of group V atoms in the droplet are found depending on the growth conditions. The estimates of the phosphorus re-evaporation coefficient from neighboring nanowires and substrate are obtained by comparing the theoretical and experimental growth rate of Ga-catalyzed GaP nanowires.

Sticking and Desorption Coefficients of As4 and As2 During Group V and Group III Controlled MBE Growth

1992 ◽  
Vol 263 ◽  
Author(s):  
Rouel Fernandez
Keyword(s):  
Activation Energy ◽  
Flux Ratio ◽  
Growth Conditions ◽  
High Energy ◽  
Controlled Growth ◽  
Sticking Coefficient ◽  
Group V ◽  
Mbe Growth ◽  
Group Iii ◽  
Sticking Coefficients

ABSTRACTReflection High Energy Electron Diffraction (RHEED) oscillations under arsenic and gallium-controlled Molecular Beam Epitaxy (MBE) growth conditions have been used to measure the sticking and desorption coefficients of As2 and As4. The coefficients are obtained from measurements of the arsenic incorporation rates. Comparisons are made with measurements obtained from desorption rates using modulated beam mass spectroscopy. The transition from gallium to arsenic-controlled growth is observed to occur after excess gallium atoms accumulate on the surface. The maximum intrinsic arsenic sticking coefficients occur when the maximum number of gallium atoms can be incorporated for a given arsenic flux. The intrinsic maximum arsenic sticking coefficients are found to be 0.75 and 0.50 for As2 and As4, respectively. During galliumcontrolled growth, the arsenic sticking coefficients are independent of substrate temperature as long as the sticking coefficient of gallium is equal to one. However, a temperature dependent maximum gallium-controlled arsenic sticking coefficient exists. It can be measured by the maximum Ga to As4 flux ratio that produces specular film surfaces. During gallium-controlled growth, the Ga to As flux ratios are shown to be equal to the gallium-controlled arsenic sticking coefficients. The activation energy for arsenic desorption during arsenic-controlled growth conditions was measured as -0.50 eV for independent As4 and As2 incident fluxes. During gallium-controlled growth with incident As4 fluxes, an activation energy for arsenic desorption of -0.70 eV was measured for the maximum gallium-controlled arsenic sticking coefficients.

Mechanism of Metalorganic MBE Growth of High Quality AlN on Si (111).

2004 ◽  
Vol 831 ◽  
Author(s):  
I. Gherasoiu ◽  
S. Nikishin ◽  
G. Kipshidze ◽  
B. Borisov ◽  
A. Chandolu ◽  
...  
Keyword(s):  
Growth Rate ◽  
Growth Parameters ◽  
In Situ Monitoring ◽  
X Ray Diffraction ◽  
High Quality ◽  
Mbe Growth ◽  
Gas Source ◽  
Surface Hydrogen ◽  
Nitrogen Bonds ◽  
Gas Source Mbe

ABSTRACTAlN constitutes the buffer layer of choice for the growth of GaN on all common substrates and its crystalline quality and surface morphology determine many of the properties of the overgrown epitaxial structure. This work systematically investigates the MOMBE growth of high quality AlN on Si (111) using trimethylaluminum and ammonia as sources of aluminum and nitrogen, respectively. Metalorganic MBE represents a hybrid growth technique that offers a combination of growth precision, in-situ monitoring and ease of source management with the promise of high material quality. We demonstrate very efficient growth, with the growth rate in excess of 500 nm/h and low ammonia consumption of less than 1 sccm. Over the entire domain of growth parameters, the surface roughness remained in the range from 12 to 53 Å rms for AlN layers up to 1000 nm thick. Here, the low values of the roughness are associated to the low growth temperature (760 °C), behavior that contrasts with that usually observed in gas source MBE with elemental Al source. X-ray diffraction linewidth as narrow as 141 arcsec has been demonstrated for samples grown under stoichiometric conditions. High temperature of the ammonia injector promotes the transition to the two-dimensional growth, while reducing the growth rate, pointing out the importance of surface hydrogen. We demonstrate that hydrogen plays an important role in the MOMBE process acting as a surfactant and passivating surface nitrogen bonds.

The Effect of Phosphine Pressure on the Band Gap of Ga0.5In0.5P

1994 ◽  
Vol 340 ◽  
Author(s):  
Sarah R. Kurtz ◽  
D. J. Arent ◽  
K. A. Bertness ◽  
J. M. Olson
Keyword(s):  
Growth Rate ◽  
Surface Structure ◽  
Band Gap ◽  
Surface Diffusion ◽  
Parameter Space ◽  
Growth Temperature ◽  
Growth Rates ◽  
Diffusion Length ◽  
Group V ◽  
Group Iii

ABSTRACTThe band gap of Ga0.51n0.5P is studied as a function of phosphine pressure, B-type substrate misorientation, growth rate, and growth temperature, with emphasis placed on the effect of the phosphine pressure. Over most of the parameter space explored (high temperatures, large substrate misorientations, and low growth rates), the band gap increases with decreasing phosphine. This increase is proposed to be caused by lower phosphorus coverage of the surface, resulting in a different surface structure that doesn't promote ordering. The implications of this effect on the observed variations of band gap with growth temperature, substrate misorientation, and growth rate are discussed. For regions of parameter space in which the ordering appears to be kinetically limited by surface diffusion, the band gap increases slightly with phosphine pressure, consistent with observations that increased group-V pressure decreases the group-III surface diffusion length.

Characterization of group Ill-nitrides by high-resolution electron microscopy

1994 ◽  
Vol 52 ◽  
pp. 846-847
Author(s):  
D. Chandrasekhar ◽  
D. J. Smith ◽  
S. Strite ◽  
M. E. Lin ◽  
H. Morkoc
Keyword(s):  
Crystal Structure ◽  
Optoelectronic Devices ◽  
High Resolution Electron Microscopy ◽  
Growth Conditions ◽  
Buffer Layers ◽  
Electromagnetic Spectrum ◽  
Group Iii ◽  
Potential Applications ◽  
Group Iii Nitride ◽  
Quality Material

The Group III-nitride semiconductors A1N, GaN, and InN are of interest for their potential applications in short wavelength optoelectronic devices. This interest stems from their direct wideband gapswhich range from 1.9 eV (InN), to 3.4 eV (GaN), to 6.2 eV (A1N). If high quality nitride films can besuccessfully grown, then optoelectronic devices with wavelengths ranging from the visible to the deepultraviolet region of the electromagnetic spectrum are theoretically possible. Recently, LED's basedon GaN and InGaN QW's were demonstrated. Also, their excellent thermal properties make them ideal candidates for high-temperature and high-power devices. Many problems plague nitride research, especiallythe lack of suitable substrate materials that are both lattice- and thermal-matched to the nitrides. The crystal structure of these materials is strongly influenced by the substrate and its orientation.For example, although the equilibrium crystal structure of these nitrides is wurtzite, zincblende phase can be nucleated under nonequilibrium growth conditions but only on cubic substrates. These zincblende nitrides represent new material systems with properties that differ from their wurtzite counterparts. Recently, good quality material has been produced employing metalorganic vapor phase epitaxy (MOVPE) and reactive molecular beam epitaxy (RMBE) techniques with incorporation of buffer layers.

MOVPE GaN Gas-Phase Chemistry for Reactor Design and Optimization

1996 ◽  
Vol 449 ◽  
Author(s):  
S. A. Safvi ◽  
J. M. Redwing ◽  
A. Thon ◽  
J. S. Flynn ◽  
M. A. Tischler ◽  
...  
Keyword(s):  
Growth Rate ◽  
Gas Phase ◽  
Growth Rates ◽  
Operating Conditions ◽  
Gas Phase Reactions ◽  
Group V ◽  
Group Iii ◽  
Design And Optimization ◽  
Gas Phase Chemistry ◽  
Phase Chemistry

ABSTRACTThe results of gas phase decomposition studies are used to construct a chemistry model which is compared to data obtained from an experimental MOVPE reactor. A flow tube reactor is used to study gas phase reactions between trimethylgallium (TMG) and ammonia at high temperatures, characteristic to the metalorganic vapor phase epitaxy (MOVPE) of GaN. Experiments were performed to determine the effect of the mixing of the Group III precursors and Group V precursors on the growth rate, growth uniformity and film properties. Growth rates are predicted for simple reaction mechanisms and compared to those obtained experimentally. Quantification of the loss of reacting species due to oligmerization is made based on experimentally observed growth rates. The model is used to obtain trends in growth rate and uniformity with the purpose of moving towards better operating conditions.

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