Elevated nighttime temperature affects fiber bundle strength via altering cellulose deposition rate during early fiber development

The structure and organization of cellulose in developing cotton fibers harvested from two cultivars of Gossypium hirsutum L. (Texas Marker-1 and TX55) at varying developmental stages from 10 to 56 days post anthesis (dpa) were investigated using wide-angle X-ray diffraction (WAXD) and Fourier transform infrared (FTIR) spectroscopy. During fiber development, the percentage crystallinity and crystallite size normal to the 200 plane increased while the full width at half maximum (FWHM) decreased. This indicates an increased alignment and decreased molecular disorder along the 200 plane as cellulose biogenesis progresses. The evolution of the WAXD parameters as a function of developmental stages provided information on the transition from the primary cell wall to the secondary cell wall and, thus, could indicate the rate of cellulose macromolecules deposition and organization during cellulose biosynthesis. These results were further confirmed by FTIR and cellulose content data. Indeed, IR ratios, cellulose content, and the integrated intensities of the vibrations 667 and 897 cm−1 showed good correlation with the percentage crystallinity. These parameters could be used as good indirect estimators of the percentage crystallinity in developing cotton fibers.

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(111) Monocrystalline Nickel Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095819 ◽

1972 ◽

Vol 30 ◽

pp. 512-513

Author(s):

T.E. Pratt ◽

R.W. Vook

Keyword(s):

Film Thickness ◽

Deposition Rate ◽

Room Temperature ◽

Narrow Range ◽

High Vacuum ◽

Residual Pressure ◽

Temperature Dependent ◽

Deposition Parameters ◽

Transmission Electron ◽

Substrate Temperatures

(111) oriented thin monocrystalline Ni films have been prepared by vacuum evaporation and examined by transmission electron microscopy and electron diffraction. In high vacuum, at room temperature, a layer of NaCl was first evaporated onto a freshly air-cleaved muscovite substrate clamped to a copper block with attached heater and thermocouple. Then, at various substrate temperatures, with other parameters held within a narrow range, Ni was evaporated from a tungsten filament. It had been shown previously that similar procedures would yield monocrystalline films of CU, Ag, and Au.For the films examined with respect to temperature dependent effects, typical deposition parameters were: Ni film thickness, 500-800 A; Ni deposition rate, 10 A/sec.; residual pressure, 10-6 torr; NaCl film thickness, 250 A; and NaCl deposition rate, 10 A/sec. Some additional evaporations involved higher deposition rates and lower film thicknesses.Monocrystalline films were obtained with substrate temperatures above 500° C. Below 450° C, the films were polycrystalline with a strong (111) preferred orientation.

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Hole Formation in Gold Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095807 ◽

1972 ◽

Vol 30 ◽

pp. 510-511

Author(s):

R. W. Vook ◽

R. Cook ◽

R. Ziemer

Keyword(s):

Deposition Rate ◽

Quartz Crystal ◽

Evaporation Rate ◽

Gold Films ◽

Hole Density ◽

Hole Formation ◽

Microscope Slide ◽

Crystal Film ◽

Glass Microscope Slide ◽

Glass Microscope

During recent experiments on Au films, a qualitative correlation between hole formation and deposition rate was observed. These early studies were concerned with films 80 to 1000A thick deposited on glass at -185°C and annealed at 170°C. In the present studies this earlier work was made quantitative. Deposition rates varying between 5 and 700 A/min were used. The effects of deposition rate on hole density for two films 300 and 700A thick were investigated.Au was evaporated from an outgassed W filament located 10 cm from a glass microscope slide substrate and a quartz crystal film thickness monitor. A shutter separating the filament from the substrate and monitor made it possible to obtain a constant evaporation rate before initiating deposition. The pressure was reduced to less than 1 x 10-6 torr prior to cooling the substrate with liquid nitrogen. The substrate was cooled in 15 minutes during which the pressure continued to drop to the mid 10-7 torr range, where deposition was begun.

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Electron-impact silane dissociation and deposition rate relationship in the PECVD of microcrystalline silicon thin films

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2001390 ◽

2001 ◽

Vol 11 (PR3) ◽

pp. Pr3-715-Pr3-722 ◽

Cited By ~ 1

Author(s):

E. Amanatides ◽

D. E. Rapakoulias ◽

D. Mataras

Keyword(s):

Thin Films ◽

Electron Impact ◽

Deposition Rate ◽

Microcrystalline Silicon ◽

Silicon Thin Films ◽

Rate Relationship

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Epitaxial Growth in Dislocation-Free Strained Alloy Films

MRS Proceedings ◽

10.1557/proc-715-a19.10 ◽

2002 ◽

Vol 715 ◽

Author(s):

Zhi-Feng Huang ◽

Rashmi C. Desai

Keyword(s):

Deposition Rate ◽

Elastic Moduli ◽

Composition Dependence ◽

Critical Thickness ◽

Lattice Misfit ◽

Misfit Strain ◽

Joint Stability ◽

Alloy Films ◽

The Stability ◽

Stability Results

AbstractThe morphological and compositional instabilities in the heteroepitaxial strained alloy films have attracted intense interest from both experimentalists and theorists. To understand the mechanisms and properties for the generation of instabilities, we have developed a nonequilibrium, continuum model for the dislocation-free and coherent film systems. The early evolution processes of surface pro.les for both growing and postdeposition (non-growing) thin alloy films are studied through a linear stability analysis. We consider the coupling between top surface of the film and the underlying bulk, as well as the combination and interplay of different elastic effects. These e.ects are caused by filmsubstrate lattice misfit, composition dependence of film lattice constant (compositional stress), and composition dependence of both Young's and shear elastic moduli. The interplay of these factors as well as the growth temperature and deposition rate leads to rich and complicated stability results. For both the growing.lm and non-growing alloy free surface, we determine the stability conditions and diagrams for the system. These show the joint stability or instability for film morphology and compositional pro.les, as well as the asymmetry between tensile and compressive layers. The kinetic critical thickness for the onset of instability during.lm growth is also calculated, and its scaling behavior with respect to misfit strain and deposition rate determined. Our results have implications for real alloy growth systems such as SiGe and InGaAs, which agree with qualitative trends seen in recent experimental observations.

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Anisotropic Plasma ChemicalVapor Deposition of Copper Films in Trenches

MRS Proceedings ◽

10.1557/proc-766-e3.8 ◽

2003 ◽

Vol 766 ◽

Author(s):

Kosuke Takenaka ◽

Masao Onishi ◽

Manabu Takenshita ◽

Toshio Kinoshita ◽

Kazunori Koga ◽

...

Keyword(s):

Chemical Vapor Deposition ◽

Deposition Rate ◽

Vapor Deposition ◽

Chemical Vapor ◽

Anisotropic Plasma ◽

Bottom Surface ◽

Chemical Vapor Deposition Method ◽

Copper Films ◽

Deposition Method ◽

Via Holes

AbstractAn ion-assisted chemical vapor deposition method by which Cu is deposited preferentially from the bottom of trenches (anisotropic CVD) has been proposed in order to fill small via holes and trenches. By using Ar + H2 + C2H5OH[Cu(hfac)2] discharges with a ratio H2 / (H2 + Ar) = 83%, Cu is filled preferentially from the bottom of trenches without deposition on the sidewall and top surfaces. The deposition rate on the bottom surface of trenches is experimentally found to increase with decreasing its width.

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