Czochralski growth and characterization of the piezoelectric single crystal La3Ga5.5Nb0.5O14

Directionally solidified Si/TaSi2 eutectic composites for the development of electronic devices (e.g. photodiodes and field-emission cathodes) were made using a Czochralski growth technique. High quality epitaxial growth of silicon on the eutectic composite substrates requires a clean silicon substrate surface prior to the growth process. Hence a preepitaxial surface cleaning step is highly desirable. The purpose of this paper is to investigate the effect of surface cleaning methods on the epilayer/substrate interface and the characterization of silicon epilayers grown on Si/TaSi2 substrates by TEM.Wafers were cut normal to the <111> growth axis of the silicon matrix from an approximately 1 cm diameter Si/TaSi2 composite boule. Four pre-treatments were employed to remove native oxide and other contaminants: 1) No treatment, 2) HF only; 3) HC1 only; and 4) both HF and HCl. The cross-sectional specimens for TEM study were prepared by cutting the bulk sample into sheets perpendicular to the TaSi2 fiber axes. The material was then prepared in the usual manner to produce samples having a thickness of 10μm. The final step was ion milling in Ar+ until breakthrough occurred. The TEM samples were then analyzed at 120 keV using the Philips EM400T.

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Spectral Investigation on the Growth and Characterization of NLO Crystals of Thiourea Succinic Acid Single Crystal.

International Journal of Science Technology and Humanities ◽

10.26524/ijsth58 ◽

2015 ◽

Vol 2 (2) ◽

pp. 70-73

Author(s):

Kannan.P ◽

Thambidurai.S ◽

Suresh.N

Keyword(s):

Single Crystal ◽

Succinic Acid ◽

Slow Evaporation Technique ◽

Absorption Studies ◽

Dta Analysis ◽

Evaporation Technique ◽

Ft Ir ◽

Ir Spectroscopic ◽

Thermal Stability Of

Growth of optically transparent single crystals of thiourea succinic acid (TUSA) was grown successfully from aqueous solution by slow evaporation technique. The crystal structure was elucidated using the single crystal XRD. The various functional groups and the modes of vibrations were identified by FT-IR spectroscopic analysis. The optical absorption studies indicate that the optical transparency window is quite wide making its suitable for NLO applications. Thermal stability of the crown crystal carried out by TGA-DTA analysis.

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Design, Analysis, and Characterization of Single Crystal Energy Harvesters for Rotorcraft Wireless Sensor Applications

Journal of the American Helicopter Society ◽

10.4050/jahs.60.022006 ◽

2015 ◽

Vol 60 (2) ◽

pp. 1-10

Author(s):

Michael V. Wozniak ◽

Stephen C. Conlon ◽

Edward C. Smith ◽

Karl M. Reichard

Keyword(s):

Single Crystal ◽

Design Analysis ◽

Wireless Sensor ◽

Energy Harvesters ◽

Sensor Applications

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Heteroleptic [Cu(P^P)(N^N)][PF6] Complexes: Effects of Isomer Switching from 2,2′-biquinoline to 1,1′-biisoquinoline

Crystals ◽

10.3390/cryst11020185 ◽

2021 ◽

Vol 11 (2) ◽

pp. 185

Author(s):

Nina Arnosti ◽

Marco Meyer ◽

Alessandro Prescimone ◽

Edwin C. Constable ◽

Catherine E. Housecroft

Keyword(s):

Crystal Structure ◽

Single Crystal ◽

Nmr Spectra ◽

Phenyl Ether ◽

Quantum Yields ◽

Dynamic Processes ◽

Electrochemical Behaviors ◽

Ambient Temperatures ◽

Π Stacking

The preparation and characterization of [Cu(POP)(biq)][PF6] and [Cu(xantphos)(biq)][PF6] are reported (biq = 1,1′-biisoquinoline, POP = bis(2-(diphenylphosphanyl)phenyl)ether, and xantphos = (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphane). The single crystal structure of [Cu(POP)(biq)][PF6] 0.5Et2O was determined and compared to that in three salts of [Cu(POP)(bq)]+ in which bq = 2,2′-biquinoline. The P–C–P angle is 114.456(19)o in [Cu(POP)(biq)]+ compared to a range of 118.29(3)–119.60(3)o [Cu(POP)(bq)]+. There is a change from an intra-POP PPh2-phenyl/(C6H4)2O-arene π-stacking in [Cu(POP)(biq)]+ to a π-stacking contact between the POP and bq ligands in [Cu(POP)(bq)]+. In solution and at ambient temperatures, the [Cu(POP)(biq)][PF6]+ and [Cu(xantphos)(biq)]+ cations undergo several concurrent dynamic processes, as evidenced in their multinuclear NMR spectra. The photophysical and electrochemical behaviors of the heteroleptic copper (I) complexes were investigated, and the effects of changing from bq to biq are described. Short Cu···O distances within the [Cu(POP)(biq)]+ and [Cu(xantphos)(biq)]+ cations may contribute to their very low photoluminescent quantum yields.

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