Surface Energy Constraints for Heteroepitaxial Growth on Compliant Substrates: Morphology of GaN Grown on Sc Layers

1996 ◽  
Vol 449 ◽  
Author(s):  
D. D. Koleske ◽  
A. E. Wickenden ◽  
J. A. Freitas ◽  
R. Kaplan ◽  
S. M. Prokes
Keyword(s):  
Low Temperature ◽  
Surface Energy ◽  
Empirical Relationship ◽  
Growth Conditions ◽  
Heteroepitaxial Growth ◽  
Nucleation Layer ◽  
Lattice Matching ◽  
Surface And Interface ◽  
Compliant Substrates ◽  
Gan Film

ABSTRACTAn empirical relationship linking surface energy to bulk modulus is presented which suggests that the thermodynamic growth mode for heteroepitaxy on compliant substrates should be 3-D. As an example of this behavior, GaN growth on Sc is shown for various growth conditions. 2-D growth is obtained when the GaN is grown on top of a low temperature GaN nucleation layer. Our results indicate that surface and interface energies, in addition to, lattice matching and thermal matching play an important role in determining the heteroexpitaxial growth morphology of GaN. There appears to be no net reduction in the dislocation density for GaN films grown on the Sc layers, because the GaN film has to be grown on a low temperature nucleation layer.

Microstructural Characterization of Heteroepitaxial SiGeC Alloys

1998 ◽  
Vol 4 (S2) ◽  
pp. 658-659
Author(s):  
David J. Smith ◽  
D. Chandrasekhar ◽  
T. Laursen ◽  
J.W. Mayer ◽  
J. Huffman ◽  
...  
Keyword(s):  
Microstructural Characterization ◽  
Growth Conditions ◽  
Group Iv ◽  
Heteroepitaxial Growth ◽  
Bandgap Engineering ◽  
Lattice Matching ◽  
Interfacial Defects ◽  
Strain Compensation ◽  
Group Iv Elements

Heteroepitaxial growth of Group IV elements on Si is attracting increased attention because of the possibility of strain compensation in addition to bandgap engineering. The incorporation of the smaller C atom into Si1-xGex binary alloys to compensate for the larger size of the Ge atom offers the prospect of lattice matching and hence strain-free growth. In our early work, ternary SiGeC alloy films with up to ∽ 2% C were epitaxial with excellent crystallinity and very few interfacial defects. However, with increased C content, the films developed considerable disorder away from the substrate and finally became amorphous. Moreover, even at low C contents (∽2-3%), it appears that substantial C is being incorporated interstitially rather than substitutionally into the covalent lattice.2 Our recent work has therefore been aimed at establishing growth conditions that enable the amount of substitutional C to be maximized while still maintaining high crystal quality.

Electron microscopic characterization of diamond thin films and substrates for diamond heteroepitaxial growth

1989 ◽  
Vol 47 ◽  
pp. 592-593
Author(s):  
J.B. Posthill ◽  
R.P. Burns ◽  
R.A. Rudder ◽  
Y.H. Lee ◽  
R.J. Markunas ◽  
...  
Keyword(s):  
Thin Films ◽  
Wide Band ◽  
Deposition Process ◽  
Heteroepitaxial Growth ◽  
Electron Microscopic ◽  
Wide Band Gap ◽  
Lattice Matching ◽  
Different Types ◽  
Diamond Thin Films

Because of diamond’s wide band gap, high thermal conductivity, high breakdown voltage and high radiation resistance, there is a growing interest in developing diamond-based devices for several new and demanding electronic applications. In developing this technology, there are several new challenges to be overcome. Much of our effort has been directed at developing a diamond deposition process that will permit controlled, epitaxial growth. Also, because of cost and size considerations, it is mandatory that a non-native substrate be developed for heteroepitaxial nucleation and growth of diamond thin films. To this end, we are currently investigating the use of Ni single crystals on which different types of epitaxial metals are grown by molecular beam epitaxy (MBE) for lattice matching to diamond as well as surface chemistry modification. This contribution reports briefly on our microscopic observations that are integral to these endeavors.

ФОРМИРОВАНИЕ ПЕРЕХОДНОГО СЛОЯ ALN НА ТЕМПЛЕЙТАХ 3С-SIC/SI(111) МЕТОДОМ АММИАЧНОЙ МОЛЕКУЛЯРНО-ЛУЧЕВОЙ ЭПИТАКСИИ

2020 ◽  
Vol 96 (3s) ◽  
pp. 148-153
Author(s):  
С.Д. Федотов ◽  
А.В. Бабаев ◽  
В.Н. Стаценко ◽  
К.А. Царик ◽  
В.К. Неволин
Keyword(s):  
Crystal Structure ◽  
Growth Rate ◽  
Low Temperature ◽  
Surface Morphology ◽  
Single Crystal ◽  
Root Mean Square Roughness ◽  
Rate Variation ◽  
Mean Square ◽  
Nucleation Layer ◽  
Low Temperature Epitaxy

Представлены результаты изучения морфологии поверхности и структуры слоев AlN, сформированных аммиачной МЛЭ на темплейтах 3C-SiC/Si(111) on-axis- и 4° off-axis-разориентации. Опробован технологический режим низкотемпературной эпитаксии зародышевого слоя AlN на поверхности 3C-SiC(111). Среднеквадратичная шероховатость поверхности (5 х 5 мкм) слоев AlN толщиной 150 ± 50 нм составила 2,5-3,5 нм на темплейтах 3C-SiC/Si(111) on-axis и 3,3-3,5 нм на 4° off-axis. Показано уменьшение шероховатости смачивающего слоя AlN при изменении скорости роста. Получены монокристаллические слои AlN(0002) со значениями FWHM (ω-геометрия) 1,4-1,6°. The paper presents the surface morphology and crystal structure of AlN layers formed by ammonia MBE on 3C-SiC/Si(111) on-axis and 4° off-axis disorientation. It offers the technological approach of low-temperature epitaxy of the AlN nucleation layer on the 3C-SiC (111) surface. Root mean square roughness (5 х 5 |xm) of AlN layers with thickness of 150 ± 50 nm was 2,5-3,5 nm onto on-axis templates and 3.3-3.5 nm onto 4° off-axis. It appears that the RMS roughness of the AlN surface is changing with the growth rate variation. Single-crystal AlN(0002) layers with FWHM values (ω-geometry) of 1.4-1.6° have been obtained.

The Effect of the Thickness of the Low Temperature AlN Nucleation Layer on the Material Properties of GaN Grown on a Double-Step AlN Buffer Layer by the MOCVD Method

2015 ◽  
Vol 45 (2) ◽  
pp. 859-866 ◽  
Author(s):  
Wei-Ching Huang ◽  
Chung-Ming Chu ◽  
Chi-Feng Hsieh ◽  
Yuen-Yee Wong ◽  
Kai-wei Chen ◽  
...  
Keyword(s):  
Low Temperature ◽  
Buffer Layer ◽  
Material Properties ◽  
Double Step ◽  
Nucleation Layer ◽  
Aln Buffer

Instabilities, Elasticity, and Wetting Effect in Multilayer Heteroepitaxial Growth

2003 ◽  
Vol 794 ◽  
Author(s):  
Zhi-Feng Huang ◽  
Rashmi C. Desai
Keyword(s):  
Periodic Structures ◽  
Morphological Evolution ◽  
Surface Profile ◽  
Theoretical Work ◽  
Semiconductor Films ◽  
Morphological Instability ◽  
Heteroepitaxial Growth ◽  
Surface And Interface ◽  
Short Period ◽  
Short Period Superlattices

ABSTRACTFor multilayer semiconductor films comprising various material layers, the coupling of elastic states in different layers as well as the nonequilibrium nature of the growing process are essential in understanding the surface and interface morphological instability and hence the growth mechanisms of nanostructures in the overall film. We present the theoretical work on the stress-driven instabilities during the heteroepitaxial growth of multilayers, based on the elastic analysis and the continuous nonequilibrium model. We develop a general theory which determines the morphological evolution of surface profile of the multilayer system, and then apply the results to two types of periodic structures that are being actively investigated: alternating tensile/compressive and strained/spacer multilayers. The wetting effect, which arises from the material properties changing across layer-layer interfaces, is incorporated. It exhibits a significant influence of stabilization on film morphology, particularly for the short-period superlattices. Our results are consistent with the experimental observations in AlAs/InAs/InP(001) and Ge/Si(001) multilayer structures.

Low-Temperature Diffusivity of Hydrogen in Different Silicon Substrates

1995 ◽  
Vol 378 ◽  
Author(s):  
Xiaojun Deng ◽  
Bhushan L. Sopori
Keyword(s):  
Low Temperature ◽  
Carbon Content ◽  
Oxygen Concentration ◽  
Hydrogen Diffusion ◽  
Growth Conditions ◽  
Growth Speed ◽  
Silicon Substrates ◽  
Vacancy Mechanism ◽  
Speed Increase

AbstractThe diffusivity of deuterium (D) at 250°C was determined in silicon samples grown by different techniques. It is found that the diffusivity increases with the growth speed, increase in carbon content and a decrease in oxygen concentration of the substrate. These growth conditions correlate well with the concentration of vacancy-type defects in the as-grown state. Hence, we conclude that a vacancy mechanism is responsible for low-temperature hydrogen diffusion in silicon. The highest diffusivity for hydrogen, calculated from these data, was found to be 3 × 10−7 cm2/s.

Detailed surface analysis of V-defects in GaN films on patterned silicon(111) substrates by metal–organic chemical vapour deposition

2019 ◽  
Vol 52 (3) ◽  
pp. 637-642 ◽  
Author(s):  
Jiang-Dong Gao ◽  
Jian-Li Zhang ◽  
Xin Zhu ◽  
Xiao-Ming Wu ◽  
Chun-Lan Mo ◽  
...  
Keyword(s):  
Growth Rate ◽  
Chemical Vapour ◽  
Direct Consequence ◽  
Growth Conditions ◽  
Organic Chemical ◽  
Film Boundary ◽  
Detailed Surface ◽  
Boundary Facet ◽  
Metal Organic ◽  
Gan Film

The growth mechanism of V-defects in GaN films was investigated. It was observed that the crystal faces of both the sidewall of a V-defect and the sidewall of the GaN film boundary belong to the same plane family of \{ {{{10\bar 11}}} \}, which suggests that the formation of the V-defect is a direct consequence of spontaneous growth like that of the boundary facet. However, the growth rate of the V-defect sidewall is much faster than that of the boundary facet when the V-defect is filling up, implying that lateral growth of \{ {{{10\bar 11}}} \} planes is not the direct cause of the change in size of V-defects. Since V-defects originate from dislocations, an idea was proposed to correlate the growth of V-defects with the presence of dislocations. Specifically, the change in size of the V-defect is determined by the growth rate around dislocations and the growth rate around dislocations is determined by the growth conditions.

Tuning metal oxide defect chemistry by thermochemical quenching

2020 ◽  
Vol 22 (11) ◽  
pp. 6308-6317
Author(s):  
Shehab Shousha ◽  
Sarah Khalil ◽  
Mostafa Youssef
Keyword(s):  
Low Temperature ◽  
Metal Oxide ◽  
Metal Oxides ◽  
First Principles ◽  
Growth Conditions ◽  
Defect Chemistry ◽  
First Principles Calculations

Based on first-principles calculations, we show how to tune the low temperature defect chemistry of metal oxides by varying growth conditions.

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