Nonlinear interaction of macrosteps on vicinal surfaces at crystal growth from vapor

Abstract Observations of slab-avalanche releases in alpine terrain have led to the hypothesis that rocky outcrops can influence the spatial distributions of temperature and heal flow in dry alpine snow covers and Unis control the local distribution of depth hoar. We investigate the effects of terrain on crystal growth by using a two-dimensional finite-clemcnl model of heal How coupled with a model of crystal growth from vapor. We used the model to examine the influence of snow properties, terrain geometry and snow depth on this phenomenon. The efleel is stronger in the early winter than in the late winter, because the rock has then had time to cool. In all cases, we found that depth-hoar growth occurs preferentially over the rock. This suggests that snow-pit investigations made over soil can he misleading if rocky outcrops are present.

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Depth-hoar growth rates near a rocky outcrop

Journal of Glaciology ◽

10.3189/s0022143000002008 ◽

1998 ◽

Vol 44 (148) ◽

pp. 477-484

Author(s):

E. M. Arons ◽

S. C. Colbeck ◽

J. M. N.T. Gray

Keyword(s):

Crystal Growth ◽

Snow Depth ◽

Late Winter ◽

Spatial Distributions ◽

Two Dimensional ◽

Local Distribution ◽

Snow Properties ◽

Rocky Outcrop ◽

Rocky Outcrops ◽

Growth From Vapor

AbstractObservations of slab-avalanche releases in alpine terrain have led to the hypothesis that rocky outcrops can influence the spatial distributions of temperature and heal flow in dry alpine snow covers and Unis control the local distribution of depth hoar. We investigate the effects of terrain on crystal growth by using a two-dimensional finite-clemcnl model of heal How coupled with a model of crystal growth from vapor. We used the model to examine the influence of snow properties, terrain geometry and snow depth on this phenomenon. The efleel is stronger in the early winter than in the late winter, because the rock has then had time to cool. In all cases, we found that depth-hoar growth occurs preferentially over the rock. This suggests that snow-pit investigations made over soil can he misleading if rocky outcrops are present.

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Numerical simulation on dumping of convection by rotating a horizontal cylinder during crystal growth from vapor

Journal of Crystal Growth ◽

10.1016/s0022-0248(98)00433-3 ◽

1998 ◽

Vol 192 (1-2) ◽

pp. 328-334 ◽

Cited By ~ 3

Author(s):

S. Fujiwara ◽

Y. Watanabe ◽

Y. Namikawa ◽

T. Keishi ◽

K. Matsumoto ◽

...

Keyword(s):

Numerical Simulation ◽

Crystal Growth ◽

Horizontal Cylinder ◽

Growth From Vapor

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The As-Grown Microtopologies of Solution Grown GaAs (001) Vicinal Surfaces

MRS Proceedings ◽

10.1557/proc-317-615 ◽

1993 ◽

Vol 317 ◽

Cited By ~ 2

Author(s):

T. Marek ◽

H.P. Strunk ◽

E. Bauser ◽

Y.C. Lu

Keyword(s):

Crystal Growth ◽

Low Temperature ◽

Growth Temperature ◽

High Growth ◽

Vicinal Surfaces ◽

Temperature Range ◽

Medium Range ◽

Parallel Growth

ABSTRACTThe observations of the as-solution-grown GaAs (001) vicinal surfaces yield three kinds of Microtopologies. Each of them develops in a certain range of growth temperature. In a low temperature range (492° C…600° C) we observe parallel growth steps with heights of one Monolayer. In a medium range, a network consisting of two sets of growth steps with larger heights is observed. At high growth temperatures (780° C…850° C) we find growth surfaces that are atomically rough. IMplications of these findings for modelling the crystal growth will be discussed.

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Surface in the studies of crystal growth from vapor phase.

Hyomen Kagaku ◽

10.1380/jsssj.6.64 ◽

1985 ◽

Vol 6 (1) ◽

pp. 64-66

Author(s):

Koichi MATSUMOTO

Keyword(s):

Crystal Growth ◽

Vapor Phase ◽

Growth From Vapor

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Montmorillonite Dendrites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052286 ◽

1974 ◽

Vol 32 ◽

pp. 454-455

Author(s):

Necip Güven ◽

Rodney W. Pease

Keyword(s):

Crystal Growth ◽

Growth Mechanism ◽

Growth Front ◽

Morphological Features ◽

Dendritic Crystal ◽

Crystal Growth Mechanism

Morphological features of montmorillonite aggregates in a large number of samples suggest that they may be formed by a dendritic crystal growth mechanism (i.e., tree-like growth by branching of a growth front).

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TEM and cathodoluminescence of precipitates in II-VI semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104509 ◽

1988 ◽

Vol 46 ◽

pp. 488-489

Author(s):

Joanna L. Batstone

Keyword(s):

Crystal Growth ◽

Band Gap ◽

Local Strain ◽

Wide Band ◽

Optoelectronic Device ◽

Wide Band Gap ◽

Bulk Crystal Growth ◽

Transmission Electron ◽

Device Applications ◽

Stoichiometry Control

Interest in II-VI semiconductors centres around optoelectronic device applications. The wide band gap II-VI semiconductors such as ZnS, ZnSe and ZnTe have been used in lasers and electroluminescent displays yielding room temperature blue luminescence. The narrow gap II-VI semiconductors such as CdTe and HgxCd1-x Te are currently used for infrared detectors, where the band gap can be varied continuously by changing the alloy composition x.Two major sources of precipitation can be identified in II-VI materials; (i) dopant introduction leading to local variations in concentration and subsequent precipitation and (ii) Te precipitation in ZnTe, CdTe and HgCdTe due to native point defects which arise from problems associated with stoichiometry control during crystal growth. Precipitation is observed in both bulk crystal growth and epitaxial growth and is frequently associated with segregation and precipitation at dislocations and grain boundaries. Precipitation has been observed using transmission electron microscopy (TEM) which is sensitive to local strain fields around inclusions.

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STM studies of crystal growth

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086179 ◽

1991 ◽

Vol 49 ◽

pp. 374-375

Author(s):

M. G. Lagally

Keyword(s):

Crystal Growth ◽

Molecular Beam ◽

Chemical Vapor ◽

Sputter Deposition ◽

Field Of View ◽

Scanning Tunneling ◽

Wide Field ◽

Tunneling Microscopy ◽

Wide Field Of View ◽

The One

It has been recognized since the earliest days of crystal growth that kinetic processes of all Kinds control the nature of the growth. As the technology of crystal growth has become ever more refined, with the advent of such atomistic processes as molecular beam epitaxy, chemical vapor deposition, sputter deposition, and plasma enhanced techniques for the creation of “crystals” as little as one or a few atomic layers thick, multilayer structures, and novel materials combinations, the need to understand the mechanisms controlling the growth process is becoming more critical. Unfortunately, available techniques have not lent themselves well to obtaining a truly microscopic picture of such processes. Because of its atomic resolution on the one hand, and the achievable wide field of view on the other (of the order of micrometers) scanning tunneling microscopy (STM) gives us this opportunity. In this talk, we briefly review the types of growth kinetics measurements that can be made using STM. The use of STM for studies of kinetics is one of the more recent applications of what is itself still a very young field.

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