Phase Formations in Co/Si, Co/Ge, and Co/Si1−xGex by Solid Phase Reactions

1993 ◽  
Vol 320 ◽  
Author(s):  
Z. Wang ◽  
Y. L. Chen ◽  
H. Ying ◽  
R. J. Nemanich ◽  
D. E. Sayers
Keyword(s):  
Thin Films ◽  
Sheet Resistance ◽  
Epitaxial Layer ◽  
Annealing Temperature ◽  
Solid Phase ◽  
The Other ◽  
Other Hand ◽  
Solid Phase Reactions

ABSTRACTPhase formations in Co thin films (200Å in thickness) reacting with atomically clean Si(100), Ge(100), and Si0.80Ge0.20 epitaxial layer (800Å in thickness on Si(100) substrates) in UHV have been investigated. For the Co/Si system, it is found that CoSi (FeSi structure) is formed at 375°C through a very disordered CoSi phase, and the final CoSi2 phase is formed at 575°C. On the other hand, the Co5Ge7 phase was identified for the Co/Ge samples annealed at 300°C and 450°C and the final CoGe2 phase is formed at 600°C. For the Co/Si0.8 Ge0.20 samples annealed from 400°C to 600°C, Co(Si1−yGey) phases with y∼0.10 were detected, and for annealing at 700°C, only the CoSi2 phase was formed. These results indicate a preferential Co- Si reaction when annealing the Co/SiGe structure. It was also found that the sheet resistance of the reacted thin films depend strongly on annealing temperature.

Oxytocin analogues with non-coded amino acid residues in position 8: [8-Neopentylglycine]oxytocin and [8-cycloleucine]oxytocin

1987 ◽  
Vol 52 (9) ◽  
pp. 2317-2325 ◽  
Author(s):  
Jan Hlaváček ◽  
Jan Pospíšek ◽  
Jiřina Slaninová ◽  
Walter Y. Chan ◽  
Victor J. Hruby
Keyword(s):  
Amino Acid ◽  
Solid Phase Synthesis ◽  
Solid Phase ◽  
The Other ◽  
Amino Acid Residues ◽  
Phase Synthesis ◽  
Other Hand ◽  
Fragment Condensation

[8-Neopentylglycine]oxytocin (II) and [8-cycloleucine]oxytocin (III) were prepared by a combination of solid-phase synthesis and fragment condensation. Both analogues exhibited decreased uterotonic potency in vitro, each being about 15-30% that of oxytocin. Analogue II also displayed similarly decreased uterotonic potency in vivo and galactogogic potency. On the other hand, analogue III exhibited almost the same potency as oxytocin in the uterotonic assay in vivo and in the galactogogic assay.

Comparison of the Potency of 8-L-Arginine, 8-D-Arginine and 8-D-Homoarginine Vasopressin Analogs with Substituted Phenylalanine in Position 2

1994 ◽  
Vol 59 (6) ◽  
pp. 1439-1450 ◽  
Author(s):  
Miroslava Žertová ◽  
Jiřina Slaninová ◽  
Zdenko Procházka
Keyword(s):  
Amino Acid ◽  
Solid Phase Synthesis ◽  
Solid Phase ◽  
Basic Amino Acid ◽  
The Other ◽  
Side Chain ◽  
Inhibitory Potency ◽  
Phase Synthesis ◽  
Other Hand ◽  
Order Of Magnitude

An analysis of the uterotonic potencies of all analogs having substituted L- or D-tyrosine or -phenylalanine in position 2 and L-arginine, D-arginine or D-homoarginine in position 8 was made. The series of analogs already published was completed by the solid phase synthesis of ten new analogs having L- or D-Phe, L- or D-Phe(2-Et), L- or D-Phe(2,4,6-triMe) or D-Tyr(Me) in position 2 and either L- or D-arginine in position 8. All newly synthesized analogs were found to be uterotonic inhibitors. Deamination increases both the agonistic and antagonistic potency. In the case of phenylalanine analogs the change of configuration from L to D in position 2 enhances the uterotonic inhibition for more than 1 order of magnitude. The L to D change in position 8 enhances the inhibitory potency negligibly. Prolongation of the side chain of the D-basic amino acid in position 8 seems to decrease slightly the inhibitory potency if there is L-substituted amino acid in position 2. On the other hand there is a tendency to the increase of the inhibitory potency if there is D-substituted amino acid in position 2.

Solid phase reactions between Fe thin films and Si-Ge layers on Si

2004 ◽  
Vol 461 (1) ◽  
pp. 81-85 ◽  
Author(s):  
C.H Yu ◽  
Y.L Chueh ◽  
S.W Lee ◽  
S.L Cheng ◽  
L.J Chen ◽  
...  
Keyword(s):  
Thin Films ◽  
Solid Phase ◽  
Solid Phase Reactions

PTCDA Films Deposited by Ionized Beam Method

1993 ◽  
Vol 316 ◽  
Author(s):  
Hiroaki Usui ◽  
Kiyoshi Kashihara ◽  
Kuniaki Tanaka ◽  
Seizo Miyata
Keyword(s):  
Thin Films ◽  
Molecular Orientation ◽  
Chemical Structure ◽  
Chemical Change ◽  
The Other ◽  
Ion Acceleration ◽  
Ionization Condition ◽  
Other Hand ◽  
Beam Method

ABSTRACTThin films of 3,4,9,10-perylenetetracarboxylic-dianhydride (PTCDA) were deposited by an ionized beam method. The molecular orientation and chemical structure of the films were studied in connection with ionization and ion acceleration conditions. At a low ionization condition, the molecules are oriented in parallel with the substrate, and the crystallinity was improved by an appropriate ion acceleration. At higher ionization conditions, on the other hand, ion acceleration resulted in a loss of crystallinity. Deposited molecules undergo chemical change in such a condition, leading to dissociation of dianhydride groups.

Variations in the Effects of Implanting Al at Different Concentrations into SiC

2006 ◽  
Vol 527-529 ◽  
pp. 831-834
Author(s):  
Kenneth A. Jones ◽  
T.S. Zheleva ◽  
Pankaj B. Shah ◽  
Michael A. Derenge ◽  
Jaime A. Freitas ◽  
...  
Keyword(s):  
Sheet Resistance ◽  
Epitaxial Layer ◽  
Partial Dislocation ◽  
Annealing Temperature ◽  
Stacking Faults ◽  
Sheet Resistivity ◽  
Complex Defect ◽  
Annealing Temperatures ◽  
Peak Intensity ◽  
The Difference

SiC samples implanted at 600°C with 1018, 1019, or 1020 cm-3 of Al to a depth of ~ 0.3 μm and annealed with a (BN)AlN cap at temperatures ranging from 1300 – 1700°C were studied. Some of the samples have been co-implanted with C or Si. They are examined using Hall, sheet resistivity, CL, EPR, RBS, and TEM measurements. In all instances the sheet resistance is larger than a comparably doped epitaxial layer, with the difference being larger for samples doped to higher levels. The results suggest that not all of the damage can be annealed out, as stable defects appear to form, and a greater number or more complex defects form at the higher concentrations. Further, the defects affect the properties of the Al as no EPR peak is detected for implanted Al, and the implanted Al reduces the AlSi peak intensity in bulk SiC. CL measurements show that there is a peak near 2.9941 eV that disappears only at the highest annealing temperature suggesting it is associated with a complex defect. The DI peaks persist at all annealing temperatures, and are possibly associated with a Si terminated partial dislocation. TEM analyses indicate that the defects are stacking faults and/or dislocations, and that these faulted regions can grow during annealing. This is confirmed by RBS measurements.

Growth of Epitaxial Site-Engineered Bi4Ti3O12-Basded Thin Films by Mocvdand Their Characterization

2002 ◽  
Vol 748 ◽  
Author(s):  
Hiroshi Funakubo ◽  
Tomohiro Sakai ◽  
Takayuki Watanabe ◽  
Minoru Osada ◽  
Masato Kakihana ◽  
...  
Keyword(s):  
Thin Films ◽  
Leakage Current ◽  
Leakage Current Density ◽  
Current Density ◽  
Spontaneous Polarization ◽  
Chemical Vapor ◽  
The Other ◽  
Other Hand ◽  
La Substitution ◽  
Lower Temperature

ABSTRACTThin films of BIT, La-substituted BIT (BLT) and La- and V-cosubstituted BIT(BLTV) were epitaxially grown on SrRuO3//SrTiO3 substrates at 850°C by metalorganic chemical vapor deposition (MOCVD), and their electrical properties were systematically compared. All films on (100), (110) and (111)-oriented substrates were epitaxially grown with (001)-, (104)-/(014)-and (118) –preferred orientations, respectively. The leakage current density of the BLTV film was almost the same with that of the BLT film, but was smaller than that of BIT film, suggesting that the La substitution contributed to the decrease of the leakage current density especially in pseudoperovskite layer. Spontaneous polarization of the BLTV film was estimated to be almost the same with the BLT film but was smaller that that of the BIT film. This is explained by the decrease of Tc with the La substitution, while V did not contribute to the change of the Curie temperature (Tc ). On the other hand, the coercive field (Ec) value of the BLTV was smaller than that of the BIT and the BLT films. As a result, La substitution contributed to the decrease of the leakage current density together with the decrease of the spontaneous polarization due to the decrease of the Tc. On the other hand, V substitution contributes to the decrease of the defects that suppress the domain motion and increases the Ec value. Therefore, each substitution of La and V plays different roles and this contribution is remarkable for the films deposited at lower temperature.

The Intercorrelation Between Microstructure and Chemicalmechanical Polish of Metal Thin Films

1999 ◽  
Vol 564 ◽  
Author(s):  
Wei-Tsu Tseng ◽  
Ying-Lang Wang
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Removal Rate ◽  
Metal Films ◽  
The Other ◽  
Metal Thin Films ◽  
Other Hand ◽  
Underlying Mechanisms ◽  
Table Speed

AbstractThe correlation between microstructures of Al and W metal thin films and their respective CMP performance is investigated. It is found that CMP removal rate decreases with increasing grain size. In both cases, the textures of the metal films are altered and their resistivity increased after CMP. The phenomenon is more pronounced for polish under a greater down force. The table speed, on the other hand, has only minimum effects on microstructure and resistivity. The possible underlying mechanisms leading to this phenomenon are proposed and their potential impacts on metallization reliability is discussed.

Solid-phase reactions, self-propagating high-temperature synthesis, and order-disorder phase transition in thin films

JETP Letters ◽  
2000 ◽  
Vol 71 (5) ◽  
pp. 183-186 ◽  
Author(s):  
V. G. Myagkov ◽  
L. E. Bykova ◽  
G. N. Bondarenko ◽  
V. S. Zhigalov ◽  
A. I. Pol’skii ◽  
...  
Keyword(s):  
Thin Films ◽  
Phase Transition ◽  
High Temperature ◽  
Solid Phase ◽  
Temperature Synthesis ◽  
Disorder Phase Transition ◽  
High Temperature Synthesis ◽  
Solid Phase Reactions

Persistent Electronic Conduction in 12CaO7Al2O3 Thin Films Produced by Ar Ion Implantation: Selective Kick-Out Effect Leads to Electride Thin Films

2004 ◽  
Vol 811 ◽  
Author(s):  
Masashi Miyakawa ◽  
Katsuro Hayashi ◽  
Yoshitake Toda ◽  
Toshio Kamiya ◽  
Masahiro Hirano ◽  
...  
Keyword(s):  
Thin Films ◽  
Ion Implantation ◽  
The Other ◽  
New Method ◽  
Electronic Conduction ◽  
High Concentration ◽  
Electronic Conductor ◽  
Other Hand

ABSTRACTA new method to convert 12CaO7Al2O3 (C12A7) thin films to electronic conductor by hot Ar+ ion implantation has been developed and its mechanism is discussed. It was found that hot Ar+ ion implantation extruded free O2- ions in C12A7 films by kick-out effects at fluences higher than 1×1017 cm−2, which left electrons in the cages embedded in C12A7 crystal and produced high concentration F+-like centers (∼1.4×1021 cm−3). The resulting films show coloration and persistent electronic conduction with conductivities up to ∼1 Scm−1. On the other hand, fluences less than 1×1017 cm−2 kept the films transparent and insulating.

scholarly journals One Internal Standard for Multiple Analytes: A Limit and Solution

2004 ◽  
Vol 87 (5) ◽  
pp. 1058-1062
Author(s):  
Li Huang ◽  
Mary Wu
Keyword(s):  
Solid Phase Extraction ◽  
Solid Phase ◽  
Internal Standard ◽  
The Other ◽  
Recovery Factor ◽  
Phase Extraction ◽  
Dilution Factor ◽  
Other Hand ◽  
Multiple Analytes

Abstract The use of a single internal standard (ephedrine-d5) as the basis for calculations of the concentrations of both the major and the minor alkaloids leads to incorrect results from variabilities in the solid-phase extraction (SPE) of the ephedra alkaloids. Because the SPE column is overloaded by ephedrine, the recovery of the internal standard, which is dependent on the dilution factor, is decreased. On the other hand, the recoveries of the minor alkaloids (methylephedrine, methylpseudoephedrine, norephedrine, and norpseudoephedrine) stay high because these compounds are less concentrated and do not overload the SPE column. Consequently, the recovery factors for the major and minor alkaloids are different, or the results are incorrect if the same recovery factor is used.

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