Importance of the Photoeffects in Rapid Isothermal Processing (RIP)

1994 ◽  
Vol 342 ◽  
Author(s):  
R. Singh ◽  
J. Mavoori ◽  
R. P. S. Thakur ◽  
S. Narayanan
Keyword(s):  
Processing Time ◽  
Radiation Spectrum ◽  
Light Sources ◽  
Next Generation ◽  
Incoherent Light ◽  
Thermal Budget ◽  
Conventional Furnace ◽  
Fundamental Understanding ◽  
Lower Temperature ◽  
Rapid Isothermal Processing

ABSTRACTThere are fundamental differences between conventional furnace processing (CFP) and rapid isothermal processing (RIP). The radiation spectrum of a conventional furnace consists of photons in the infrared and longer wavelength regions, whereas the spectrum of the incoherent light sources used in RIP consist of some ultraviolet, visible, and infrared photons. As compared to CFP, the photophysical and photochemical effects associated with RIP provide the capability of lower temperature processing. Due to photoeffects in RIP, differences are observed in junction movement and defect evolution with different lamp configurations and different kinds of lamps having differing spectra. This implies that diffusion models, in addition to considering processing time and temperature, should also account for the lamp configurations and spectra of the heating sources. The fundamental understanding of photoeffects in RIP can be further exploited to reduce the overall thermal budget used in the manufacturing of semiconductor devices. In this paper we present our study of photoeffects in RIP, which can be of help in the design of the next generation of RIP equipment.

In-situ Rapid Isiheial Pocessing of Thin Epitaxial Dieleciric Films on Silicon and Compound Semi Semiconductors

1986 ◽  
Vol 75 ◽  
Author(s):  
R. Singh ◽  
F. Radpour ◽  
J. Narayan ◽  
S. P. Joshi ◽  
M. Rahati ◽  
...  
Keyword(s):  
Isothermal Annealing ◽  
Structural Characteristics ◽  
Processing Technique ◽  
Dielectric Films ◽  
Light Sources ◽  
Incoherent Light ◽  
Beam System ◽  
Rapid Isothermal Processing

AbstracrWe have developed a new rapid isothermal processing technique for the deposition of epitaxial dielectric films (II–VIa fluorides and their mixtures) on silicon and ccmpound semiconductors. In this process, epitaxial dielectric films are deposited in an e-beam system at room teqperature and subsequently subjected to in-situ rapid isothermal annealing by using incoherent light sources incorporated in the e-beam system. Epitaxial dielectric films of CaF2 and CaxS1−xF2 have been deposited on Si, GaAs and InP. In this paper, prelimilifty results of electrical and structural characteristics of. epitaxial dielectric films on Si and cupourd semiconductors are presented.

Chitosan-Nanocellulose Composites for Regenerative Medicine Applications

2020 ◽  
Vol 27 (28) ◽  
pp. 4584-4592 ◽  
Author(s):  
Avik Khan ◽  
Baobin Wang ◽  
Yonghao Ni
Keyword(s):  
Regenerative Medicine ◽  
Preparation Method ◽  
Chemical Properties ◽  
Biological Properties ◽  
Next Generation ◽  
Structure Property ◽  
Physico Chemical ◽  
Structure Property Relationship ◽  
Attractive Candidate ◽  
Fundamental Understanding

Regenerative medicine represents an emerging multidisciplinary field that brings together engineering methods and complexity of life sciences into a unified fundamental understanding of structure-property relationship in micro/nano environment to develop the next generation of scaffolds and hydrogels to restore or improve tissue functions. Chitosan has several unique physico-chemical properties that make it a highly desirable polysaccharide for various applications such as, biomedical, food, nutraceutical, agriculture, packaging, coating, etc. However, the utilization of chitosan in regenerative medicine is often limited due to its inadequate mechanical, barrier and thermal properties. Cellulosic nanomaterials (CNs), owing to their exceptional mechanical strength, ease of chemical modification, biocompatibility and favorable interaction with chitosan, represent an attractive candidate for the fabrication of chitosan/ CNs scaffolds and hydrogels. The unique mechanical and biological properties of the chitosan/CNs bio-nanocomposite make them a material of choice for the development of next generation bio-scaffolds and hydrogels for regenerative medicine applications. In this review, we have summarized the preparation method, mechanical properties, morphology, cytotoxicity/ biocompatibility of chitosan/CNs nanocomposites for regenerative medicine applications, which comprises tissue engineering and wound dressing applications.

scholarly journals Mechanochemically-Assisted Synthesis of Lead-Free Piezoelectric CaZrO3-Modified (K,Na,Li)(Nb,Ta)O3-Solid Solution

Ceramics ◽  
2018 ◽  
Vol 1 (2) ◽  
pp. 304-318 ◽  
Author(s):  
Kristian Radan ◽  
Brigita Kmet ◽  
Silvo Drnovšek ◽  
Uroš Prah ◽  
Tadej Rojac ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Solid State ◽  
Processing Time ◽  
Piezoelectric Properties ◽  
Mechanochemical Activation ◽  
Solid State Synthesis ◽  
Lead Free ◽  
Compositional Homogeneity ◽  
Lower Temperature ◽  
Conventional Solid State Synthesis

Lead-free piezoelectric 0.95(Na0.49K0.49Li0.02)(Nb0.8Ta0.2)O3–0.05CaZrO3 with 2 wt % MnO2 addition was prepared using mechanochemically-assisted solid-state synthesis. Upon mechanochemical activation of the mixture of reagents partial amorphization occurs which contributes to a significantly lower temperature of completion of the solid-state reaction, ~600 °C as opposed to ~700 °C for the conventional solid-state synthesis as determined by thermal analysis. The ceramic specimens prepared by the mechanochemically-assisted route exhibit improved compositional homogeneity and slightly enhanced piezoelectric properties, achieved in a considerably shorter processing time compared to the conventional solid-state synthesis route, which was studied as a reference.

Incoherent Light Sources

2007 ◽  
pp. 565-582 ◽  
Author(s):  
Dietrich Bertram ◽  
Matthias Born ◽  
Thomas Jüstel
Keyword(s):  
Light Sources ◽  
Incoherent Light

Incoherent Light Sources

2018 ◽  
pp. 561-578
Author(s):  
Zacarías Malacara-Hernández
Keyword(s):  
Light Sources ◽  
Incoherent Light

Fluidized bed heat treatment of aluminum cast components

2004 ◽  
Vol 120 ◽  
pp. 555-562
Author(s):  
D. Apelian ◽  
S. K. Chaudhury
Keyword(s):  
Heat Treatment ◽  
Fluidized Bed ◽  
Processing Time ◽  
Reaction Times ◽  
Experimental Results ◽  
Fluidized Bed Reactors ◽  
The Past ◽  
Conventional Furnace ◽  
Time Required ◽  
Solutionizing Time

Heat Treatment and post casting treatments of cast components has always been an important step in the control of microstructure, and resultant properties. In the past, the solutionizing, quenching and ageing process steps may have “required” in total over 20 hours of processing time. With the advent of fluidized bed reactors (FB), processing time has been dramatically reduced. For example, instead of 8-10 hours solutionizing time in a conventional furnace, the time required in FB is less than an hour. Experiments with Al-Si-Mg alloy, (both modified with Sr, and unmodified) were performed, having different diffusion distances (different DAS), and for different reaction times and temperatures. Both the model and the experimental results are presented and discussed.

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