Bi induced step-flow growth in the homoepitaxial growth of Au(111)

Homoepitaxial growth of step-flow single crystal diamond was performed by microwave plasma chemical vapor deposition system on high-pressure high-temperature diamond substrate. A coarse surface morphology with isolated particles was firstly deposited on diamond substrate as an interlayer under hillock growth model. Then, the growth model was changed to step-flow growth model for growing step-flow single crystal diamond layer on this hillock interlayer. Furthermore, the surface morphology evolution, cross-section and surface microstructure, and crystal quality of grown diamond were evaluated by scanning electron microscopy, high-resolution transmission electron microcopy, and Raman and photoluminescence spectroscopy. It was found that the surface morphology varied with deposition time under step-flow growth parameters. The cross-section topography exhibited obvious inhomogeneity in crystal structure. Additionally, the diamond growth mechanism from the microscopic point of view was revealed to illustrate the morphological and structural evolution.

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4H-SiC Homoepitaxial Growth on Substrates with Different Off-Cut Directions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.679-680.55 ◽

2011 ◽

Vol 679-680 ◽

pp. 55-58 ◽

Cited By ~ 5

Author(s):

Birgit Kallinger ◽

Bernd Thomas ◽

Patrick Berwian ◽

Jochen Friedrich ◽

Gerd Trachta ◽

...

Keyword(s):

Growth Process ◽

Screw Dislocations ◽

Force Microscopy ◽

Step Flow ◽

Homoepitaxial Growth ◽

Atomic Force ◽

P Type ◽

Step Flow Growth ◽

Edge Dislocations ◽

Doping Range

Homoepitaxial growth on 4° off-axis substrates with different off-cut directions, i.e. [11-20] and [1-100], was investigated using a commercial CVD reactor. The characteristics of the growth process on substrates with different off-cut directions were determined with respect to applicable C/Si ratio, growth rate and n- and p-type doping range. Stable step flow growth was achieved over a broad range of C/Si ratio at growth rates ~ 15 µm/h in both cases. The n-type doping level of epilayers can be controlled at least in the range from 5  1014 cm-3 to 3  1017 cm-3 on both types of substrates. Highly p-type epilayers with p = 2  1019 cm-3 can also be grown on [1-100] off-cut substrates. Hence, the growth process for standard substrates was successfully transferred to [1-100] off-cut substrates resulting in epilayers with similar doping levels. The dislocation content of the grown epilayers was investigated by means of defect selective etching (DSE) in molten KOH. For both off-cut directions of the substrates, similar densities of threading edge dislocations (TED), threading screw dislocations (TSD) and basal plane dislocations (BPD) were found in the epilayers. Epilayers with very low BPD density can be grown on both kinds of substrates. The remaining BPDs in epilayers are inclined along the off-cut direction of the substrate. The surface morphology and roughness was investigated by atomic force microscopy (AFM). The epilayers grown on [1-100] off-cut substrates are smoother than those on standard substrates.

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Molecular beam homoepitaxial growth of MgO(001)

Journal of Materials Research ◽

10.1557/jmr.1994.2944 ◽

1994 ◽

Vol 9 (11) ◽

pp. 2944-2952 ◽

Cited By ~ 44

Author(s):

S.A. Chambers ◽

T.T. Tran ◽

T.A. Hileman

Keyword(s):

Electron Spectroscopy ◽

High Speed ◽

Molecular Beam ◽

Step Flow ◽

Homoepitaxial Growth ◽

Crystallographic Order ◽

Step Flow Growth ◽

First Time

We describe homoepitaxial growth and detailed in situ characterization of MgO(001). We have used, for the first time, high-speed Auger electron spectroscopy as a real-time probe of film composition during growth. Excellent short-range and long-range crystallographic order are achieved in films grown to a thickness of several hundred angstroms in the substrate temperature range of 450 °C to 750 °C. Moreover, the films become more laminar as the growth temperature increases, suggesting that MgO grows homoepitaxially by the step-flow growth mechanism at elevated temperature. The surfaces of films grown at 650°and 750 °C are smoother than those obtained by cleaving MgO(001).

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Two-Dimensional Nucleation of Cubic and 6H Silicon Carbide

Materials Science Forum ◽

10.4028/www.scientific.net/msf.615-617.189 ◽

2009 ◽

Vol 615-617 ◽

pp. 189-192 ◽

Cited By ~ 11

Author(s):

Remigijus Vasiliauskas ◽

Mikael Syväjärvi ◽

Milena Beshkova ◽

Rositza Yakimova

Keyword(s):

Substrate Surface ◽

Growth Mode ◽

Spiral Growth ◽

Heteroepitaxial Growth ◽

Step Flow ◽

Homoepitaxial Growth ◽

Unit Cell Size ◽

Initial Stage ◽

Higher Temperature ◽

Step Flow Growth

The initial stage of heteroepitaxial growth of 3C-SiC and homoepitaxial growth of 6H-SiC on nominal 6H-SiC on-axis substrates has been studied. Before 3C-SiC starts to nucleate, 6H-SiC grows in a step-flow growth mode due to a slight off-orientation of the substrate surface already at about 1500oC. In the 1650-1700oC temperature interval 3C-SiC nucleates as 2D islands. A distance away from the 3C-SiC island 6H-SiC grows in step-flow mechanism. In the vicinity of the 3C-SiC islands the 6H-SiC growth steps start to change direction and even split into two steps with the equal height of 0.5 nm, which is approaching the unit cell size of cubic SiC. When the supersaturation is lower in comparison with the conditions for 3C-SiC growth, there is only formation of 6H-SiC, i.e. homoepitaxial growth. The growth mode of 6H-SiC is dependent on temperature. At the lowest temperature there is spiral growth while at higher temperature 2D nucleation is preferred.

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Temperature-Dependent Photoluminescence of ZnO Thin Films Grown on Off-Axis SiC Substrates by APMOCVD

Materials ◽

10.3390/ma14041035 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1035

Author(s):

Ivan Shtepliuk ◽

Volodymyr Khranovskyy ◽

Arsenii Ievtushenko ◽

Rositsa Yakimova

Keyword(s):

Optical Properties ◽

Structural Quality ◽

Organic Chemical ◽

Zno Films ◽

Vicinal Surfaces ◽

Temperature Dependent ◽

Step Flow ◽

Step Flow Growth ◽

First Time ◽

Temperature Dependent Photoluminescence

The growth of high-quality ZnO layers with optical properties congruent to those of bulk ZnO is still a great challenge. Here, for the first time, we systematically study the morphology and optical properties of ZnO layers grown on SiC substrates with off-cut angles ranging from 0° to 8° by using the atmospheric pressure meta–organic chemical vapor deposition (APMOCVD) technique. Morphology analysis revealed that the formation of the ZnO films on vicinal surfaces with small off-axis angles (1.4°–3.5°) follows the mixed growth mode: from one side, ZnO nucleation still occurs on wide (0001) terraces, but from another side, step-flow growth becomes more apparent with the off-cut angle increasing. We show for the first time that the off-cut angle of 8° provides conditions for step-flow growth of ZnO, resulting in highly improved growth morphology, respectively structural quality. Temperature-dependent photoluminescence (PL) measurements showed a strong dependence of the excitonic emission on the off-cut angle. The dependences of peak parameters for bound exciton and free exciton emissions on temperature were analyzed. The present results provide a correlation between the structural and optical properties of ZnO on vicinal surfaces and can be utilized for controllable ZnO heteroepitaxy on SiC toward device-quality ZnO epitaxial layers with potential applications in nano-optoelectronics.

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Growth of (Zn)CdSe quantum structures on vicinal GaAs(001) substrates: step flow growth versus strain effects

Journal of Crystal Growth ◽

10.1016/s0022-0248(00)00162-7 ◽

2000 ◽

Vol 214-215 ◽

pp. 606-609 ◽

Cited By ~ 5

Author(s):

T Passow ◽

H Heinke ◽

D Kayser ◽

K Leonardi ◽

D Hommel

Keyword(s):

Quantum Structures ◽

Strain Effects ◽

Step Flow ◽

Step Flow Growth ◽

Versus Strain

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Development of Cross-Hatch Morphology During Growth of Lattice Mismatched Layers

MRS Proceedings ◽

10.1557/proc-673-p5.2 ◽

2001 ◽

Vol 673 ◽

Author(s):

A. Maxwell Andrews ◽

J.S. Speck ◽

A.E. Romanov ◽

M. Bobeth ◽

W. Pompe

Keyword(s):

Misfit Dislocation ◽

Film Growth ◽

Strain Relaxation ◽

Dislocation Generation ◽

Force Microscopy ◽

Step Flow ◽

Atomic Force ◽

Subsequent Step ◽

Step Flow Growth ◽

Lateral Scale

ABSTRACTAn approach is developed for understanding the cross-hatch morphology in lattice mismatched heteroepitaxial film growth. It is demonstrated that both strain relaxation associated with misfit dislocation formation and subsequent step elimination (e.g. by step-flow growth) are responsible for the appearance of nanoscopic surface height undulations (0.1-10 nm) on a mesoscopic (∼100 nm) lateral scale. The results of Monte Carlo simulations for dislocation- assisted strain relaxation and subsequent film growth predict the development of cross-hatch patterns with a characteristic surface undulation magnitude ∼50 Å in an approximately 70% strain relaxed In0.25Ga0.75As layers. The model is supported by atomic force microscopy (AFM) observations of cross-hatch morphology in the same composition samples grown well beyond the critical thickness for misfit dislocation generation.

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