Early stages of growth and crystal structure evolution of boron nitride thin films

Our understanding of the structure and the formation of inorganic minerals in the bivalve shells has been considerably advanced by the use of electron microscope. However, very little is known about the ultrastructure of valves in the larval stage of the oysters. The present study examines the developmental changes which occur between the time of conception to the early stages of Dissoconch in the Crassostrea virginica(Gmelin), focusing on the initial deposition of inorganic crystals by the oysters.The spawning was induced by elevating the temperature of the seawater where the adult oysters were conditioned. The eggs and sperm were collected separately, then immediately mixed for the fertilizations to occur. Fertilized animals were kept in the incubator where various stages of development were stopped and observed. The detailed analysis of the early stages of growth showed that CaCO3 crystals(aragonite), with orthorhombic crystal structure, are deposited as early as gastrula stage(Figuresla-b). The next stage in development, the prodissoconch, revealed that the crystal orientation is in the form of spherulites.

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7451. Atomic morphology of thin films in the early stages of growth

Vacuum ◽

10.1016/0042-207x(91)91519-t ◽

1991 ◽

Vol 42 (10-11) ◽

pp. 668

Keyword(s):

Thin Films ◽

Stages Of Growth ◽

Early Stages

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Early Stages of Growth of BaTiO3 Thin-Films

MRS Proceedings ◽

10.1557/proc-200-237 ◽

1990 ◽

Vol 200 ◽

Cited By ~ 3

Author(s):

M. Grant Norton ◽

Gerald R. English ◽

C. Barry Carter

Keyword(s):

Thin Films ◽

Film Growth ◽

Lattice Mismatch ◽

Pulsed Laser ◽

Surface Preparation ◽

Thin Foil ◽

Stages Of Growth ◽

Early Stages ◽

Transmission Electron ◽

Film Nucleation

ABSTRACTBarium titanate (BaTiO3) is of interest for use in a number of thin-film applications in electronic and optoelectronic devices. For these devices the formation of epitactic films of the correct stoichiometry and phase is essential. The substrate is important during the early stages of growth in the establishment of epitaxy, factors such as lattice mismatch, surface preparation and crystallographic orientation can all affect film nucleation and growth. In this study thin-films of BaTiO3 have been formed using the pulsed-laser ablation technique. The early stages of film growth have been studied directly using transmission electron microscopy by examination of very thin films deposited onto specially prepared electron-transparent thin-foil substrates.

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Growth and Structure of in-plane Textured MgO Thin Films Deposited on Amorphous Substrates using ion-beam-assisted E-Beam Evaporation

MRS Proceedings ◽

10.1557/proc-504-301 ◽

1997 ◽

Vol 504 ◽

Cited By ~ 1

Author(s):

Connie P. Wang ◽

Khiem B. Do ◽

Ann F. Marshall ◽

Theodore H. Geballe ◽

Malcolm R. Beasley ◽

...

Keyword(s):

Thin Films ◽

Cross Section ◽

Film Growth ◽

Early Stage ◽

Ion Beam ◽

Electron Beam Evaporation ◽

Grain Structure ◽

Structure Evolution ◽

Stages Of Growth ◽

Amorphous Substrates

ABSTRACTIn-plane aligned MgO thin films (∼100Å) have been obtained on various amorphous substrates by Ar+ ion-assisted electron-beam evaporation. Based on RHEED and cross-section TEM, we have shown that the MgO texture appears at a very early stage of film growth and is optimized at a thickness of around 100Å. Optimal thickness is the stage at which the surface is fully covered by MgO crystallites. The planar-view TEM of grain structure evolution in samples at different stages of growth reveals the dynamics of the texture developing process. Small, (100)-faceted MgO grains were observed both in planar-view and cross-section TEM images.

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