ChemInform Abstract: Growth, Morphology and Structural Perfection of Dislocation-Free Si Tetracrystals.

Thin layers of III-V semiconductors, such as quantum well structures and strained layer superlattices (SLS's), are currently of great interest. However, there have been widely scattered reports suggesting that thin layers and SLS's with arbitrarily large strain and thicknesses are difficult if not impossible to grow. In this work we studied the nucleation, morphology and structural perfection of a wide variety of thin layers in the GaAs/GalnAsP system. These epitaxial layers were grown by atmospheric pressure MOCVD. The GaAs/GalnAs system is mismatched through the entire compositional range, the extreme mismatch being 7% for GaAs/lnAs. The nucleation and growth morphology of GalnAs layers on GaAs were observed to be very strongly dependent on the mismatch (i.e. the In concentration x) This is clearly depicted in Fig. 1 which shows secondary electron micrographs of the surface of three GalnAs layers grown for 30 sec. using the same growth rate of 600 Å min-1.

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High resolution in-situ interferometric studies of lysozyme crystal growth morphology and kinetics

10.2514/6.1995-3579 ◽

1995 ◽

Author(s):

Peter Vekilov ◽

Franz Rosenberger

Keyword(s):

Crystal Growth ◽

High Resolution ◽

Growth Morphology ◽

Lysozyme Crystal

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Copper to Aluminum Bonding: IMC Characterization through New Mechanical Sectioning Methods

ISTFA 2010: Conference Proceedings from the 36th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2010p0181 ◽

2010 ◽

Author(s):

Lucas Copeland ◽

Mukul Saran

Keyword(s):

Intermetallic Compound ◽

Imaging Study ◽

Thermal Ageing ◽

Initial Model ◽

Growth Morphology ◽

Intermetallic Formation ◽

Imaging Parameters ◽

Bonded Interface ◽

Bond Interface ◽

Sem Imaging

Abstract This paper presents a mechanical cross-sectioning approach that produces an image clarity not yet demonstrated in published literature. It demonstrates how a critical sequence of polishing, basic slurry optimization and staining, in conjunction with correct imaging parameters can be used to highlight the growth morphology of the intermetallic compound (IMCs). Utilizing this approach, the paper describes the results of a SEM imaging study of the intermetallic formation and growth at the Cu-Al bond interface during thermal ageing for up to 4000hrs at 150 deg C. The paper uses direct SEM imaging to catalog observations which are used to create an initial model for IMC and void growth at the wire bonded interface. It examines the effect of aluminum splash and concludes that growth of intermetallics at the Cu-Al interface is rapid into the bond-pad aluminum than into the Cu-ball, but the growth thickness uniformity is much higher into the Cu-ball.

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Theoretical Study on the Effect of Solvent Behavior on Ammonium Dinitramide (ADN)/1,4,7,10,13,16‐Hexaoxacyclooctadecane (18‐Crown‐6) Cocrystal Growth Morphology at Different Temperatures

Crystal Research and Technology ◽

10.1002/crat.202000203 ◽

2021 ◽

pp. 2000203

Author(s):

Hong Xie ◽

Rui‐jun Gou ◽

Shu‐hai Zhang

Keyword(s):

Theoretical Study ◽

Ammonium Dinitramide ◽

Growth Morphology ◽

Effect Of Solvent ◽

Different Temperatures

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Effect of Bias Voltage on Microstructure and Properties of Tantalum Nitride Coatings Deposited by RF Magnetron Sputtering

Coatings ◽

10.3390/coatings11080911 ◽

2021 ◽

Vol 11 (8) ◽

pp. 911

Author(s):

Wei Dai ◽

Yunzhan Shi

Keyword(s):

Magnetron Sputtering ◽

Bias Voltage ◽

Rf Magnetron Sputtering ◽

Amorphous Structure ◽

Tribological Performance ◽

Tantalum Nitride ◽

Growth Morphology ◽

Low Friction ◽

Nitride Coatings ◽

Overall Performance

TaNx coatings were deposited by RF magnetron sputtering with different bias voltages. The growth morphology, crystalline structure, chemical bond structure, hardness and elastic modulus, adhesion strength and tribological performance of the coatings were studied as a function of the bias voltage. The results showed that an increasing bias voltage refines the coating grains and facilitates structure densification. Simultaneously, the structure of the TaNx coatings transfers from a composite structure consisting of TaN and Ta2N crystals, through a single composite mainly composed of the Ta2N crystal, to an amorphous structure as the bias voltage increases from low to high, indicating that the phase composition of the TaNx coatings can be varied by the bias voltage. The coating composed of Ta2N crystal showed a good overall performance including enhanced hardness, enhanced adhesive strength, and good tribological performance with enhanced wear resistance and a low friction coefficient of 0.18.

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