Influence of miscut angle of Si(111) substrates on the performance of InGaN LEDs

ABSTRACTIn this study, we investigate the dependence of GaN surface morphology on the absolute strain values for thin (<10 μm) epitaxial films grown by MOCVD on c-plane sapphire substrates of various miscut angles towards the m-plane. Results indicate an excellent correlation between the surface roughness observed employing an AFM tool and epilayer strain values. An overall increase of surface roughness (decrease of atomic terrace width) is found with decreasing compressive strain (epilayer vs. bulk value). In addition, sapphire substrates with increasing miscut angle (0.30 deg) appear to relax the inherent, built-in strain differently in the vertical (growth) direction when compared to just (0.00 deg) substrates. Strain relaxation by typical V-shaped, hexagonal pits is directly imaged through the comparison of surface features inside and outside of pits in the thin GaN epilayer films.

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AFM study of surface topography of InP epilayers: effect of miscut angle and growth temperature during MOVPE

Proceedings of 8th International Conference on Indium Phosphide and Related Materials ◽

10.1109/iciprm.1996.492291 ◽

2002 ◽

Author(s):

V. Souliere ◽

V. Thevenot ◽

H. Dumont ◽

Y. Monteil ◽

J. Bouix ◽

...

Keyword(s):

Surface Topography ◽

Growth Temperature ◽

Miscut Angle

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Growth Mechanisms and Surface Morphology of Ybco Based High-Tc Thin Films and Heterostructures for sns Junctions

MRS Proceedings ◽

10.1557/proc-574-17 ◽

1999 ◽

Vol 574 ◽

Author(s):

R. A. Rao ◽

C. B. Eom

Keyword(s):

Thin Films ◽

Surface Morphology ◽

Spiral Growth ◽

High Tc ◽

Ybco Films ◽

Step Flow ◽

Pseudomorphic Growth ◽

Growth Features ◽

High Degree ◽

Miscut Angle

AbstractWe have controlled the nanoscale growth mechanism and surface morphology of YBa2Cu3O7 (YBCO) based high-Tc thin films and heterostructures, using miscut SrTiO3 substrates. On exact (001) SrTiO3 substrates, the YBCO films grow in a screw dislocation growth mode. The barrier layers (La6.4Sr1.6Cu8O20 and PrBa2Cu3O7) grown on top of such a YBCO film also show spiral growth features, indicating pseudomorphic growth. On miscut substrates (with miscut angle ≥ 4° toward [010]) the YBCO films grow by step-flow. However, the La6.4Sr1. 6Cu8O20 layers grown on such YBCO bottom electrodes, show a high degree of step bunching with rough surface. In contrast, the PrBa2Cu3O7 layers show clear step-terrace surface morphology similar to the underlying YBCO bottom electrode, suggesting the existence of periodic nanoscale steps at the S-N interface. These heterostructures can be used for the fabrication of SNS Josephson junctions to take advantage of the proximity effect coupling at the nanoscale steps at the interface.

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Measurement of the miscut angle of crystal surfaces vicinal to major crystal planes by x‐ray diffractometry at glancing incidence

Applied Physics Letters ◽

10.1063/1.100313 ◽

1988 ◽

Vol 53 (21) ◽

pp. 2042-2043 ◽

Cited By ~ 5

Author(s):

S. E. G. Slusky ◽

A. T. Macrander

Keyword(s):

Crystal Surfaces ◽

X Ray ◽

Miscut Angle

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Molecular Beam Epitaxial Growth Mode Transitions on Vicinal Surfaces

MRS Proceedings ◽

10.1557/proc-399-47 ◽

1995 ◽

Vol 399 ◽

Cited By ~ 1

Author(s):

V.I. Trofimov ◽

B.K. Medvedev ◽

V.G. Mokerov ◽

A.G. Shumyankov

Keyword(s):

Growth Mode ◽

Rate Equations ◽

Transition Curve ◽

Flow Mode ◽

Mbe Growth ◽

Step Flow ◽

Molecular Beam Epitaxial ◽

Mode Transitions ◽

Molecular Beam Epitaxial Growth ◽

Miscut Angle

ABSTRACTKinetic model of MBE growth on vicinal surface is investigated. The model includes step propagation, nucleation and growth of islands on the terraces and Schwoebel barrier at descending step edges as -well. By numerical solution of kinetic rate equations for growth on stepped surface, adatom and island density profiles across a terrace are obtained. With using simple criterion for growth mode transition the "phase diagram" of growth modes in parametric space γ–β is constructed, γ∼J/D and β∼tan-2φ, where J is the atomic flux, D is the surface diffusion coefficient and φ is the substrate miscut angle. The transition curve in the γ–β plane separating step flow mode region from the mixed (step-flow+nucleation) growth mode region is well describded by a simple equation γ=A/β3 where constant A=10 and 100 with and without Schwoebel effect. The relations for critical terrace width (miscut angle) and transition temperature are derived and it is shown that these relations are in fairly well agreement with available experimental data on the MBE growth of GaAs.

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Control of the morphology of oxide nano-islands through the substrate miscut angle

Progress in Solid State Chemistry ◽

10.1016/j.progsolidstchem.2005.11.017 ◽

2005 ◽

Vol 33 (2-4) ◽

pp. 327-332 ◽

Cited By ~ 8

Author(s):

R. Bachelet ◽

G. Nahélou ◽

A. Boulle ◽

R. Guinebretière ◽

A. Dauger

Keyword(s):

Miscut Angle

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BEHAVIOR OF STEP EDGES ON Si(001)

Modern Physics Letters B ◽

10.1142/s0217984993001582 ◽

1993 ◽

Vol 07 (24n25) ◽

pp. 1547-1566 ◽

Cited By ~ 3

Author(s):

H.J.W. ZANDVLIET ◽

H.B. ELSWIJK

Keyword(s):

Room Temperature ◽

Step Edge ◽

The Other ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Step Step ◽

Formation Energies ◽

Stm Images ◽

Miscut Angle ◽

Step Edges

The morphology of monatomic step edges on vicinal Si (001) surfaces is briefly reviewed. With increasing miscut angle, the Si (001) surface exhibits an interesting sequence of phase transitions. For a miscut angle smaller than about 0.03°, a hilly structure with step loops is found, whereas a phase of wavy steps coexisting with a phase of straight steps is observed in the range of 0.03°–0.1°. If the miscut angle lies in the range of 0.1° up to about 3°, two types, one much straighter than the other, of monatomic step edges develop. For even larger miscut angles, a phase of straight biatomic step edges is found. The fundamental energetic parameters, like kink formation energies, step edge energies and step-step interactions, which govern the thermodynamic behavior are determined using Scanning Tunneling Microscopy (STM) images of 0.5° misoriented Si (001). Despite the weak strength of energetic and entropic step-step interactions as compared to the interactions along the step edge, i.e. the kink formation and step edge energies, they have a profound effect on the meandering of the step edges. Both entropic and energetic step-step interactions are proportional to L−2 (where L is the average terrace length). The behavior of the step edges at temperatures above room temperature will be addressed with the aid of a high-temperature STM. The freeze-out temperature, T f , of the monatomic step edges is estimated to be higher than 600–700 K. The temperature T f is significantly above the roughening temperature, Tr, of the step edges. This means that at room temperature, the monatomic step edges on vicinal Si (001) are always rough.

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