Oxygen-Trapping and Oxidation Induced by Laser Irradiation in Silicon

1981 ◽  
Vol 4 ◽  
Author(s):  
Yung S. Liu ◽  
Shin-Wu Chiang ◽  
W. Katz

ABSTRACTRapid oxidation in silicon induced by nanosecond UV laser pulses has been recently reported [1]. A significant amount of oxygen was observed to be incorporated in theregrown silicon layer when irradiation took place in air or in oxygen ambient. The fundamental interaction and transport kinetics involved include: incorporation of impurity during surface melting, trapping of solute during resolidification, and rapid reaction to form chemical bonds. The present study has investigated the mechanism of oxygen incorporation and trapping under various regrowth conditions. Oxygen depth-concentration distributions were analyzed using secondary-ion-mass spectroscopy (SIMS). The oxide formed was studied using differential Fourier-Transformed IR (FT-IR) spectroscopy.

2021 ◽  
Vol 6 (27) ◽  
pp. 6957-6972
Author(s):  
Cristina M. Muntean ◽  
Rǎzvan Ştefan ◽  
Alexandra Tǎbǎran ◽  
Carmen Tripon ◽  
Attila Bende ◽  
...  

1988 ◽  
Vol 42 (6) ◽  
pp. 997-1004 ◽  
Author(s):  
D. B. Parry ◽  
J. M. Harris

Attenuated total reflection (ATR) FT-IR spectroscopy has been adapted to measure the rates of chemical modification reactions at silica surfaces. In this method, a silicon ATR crystal is oxidized at 1000°C under dry O2 to produce a silicon dioxide layer on the crystal surface, the thickness of which can be measured using ellipsometry. The oxidized silicon layer is then used as a model silica surface in measurements of the rates of chemical modification. A flow cell is filled with a solution of a surface active reagent. ATR infrared spectra are obtained at regular time intervals, where confinement of the intensity to the interface by total internal reflection provides a measure of local changes in concentration of species which adsorb or bind to the surface. The effect of the silicon dioxide layer on the sensitivity of measuring absorbance at the silica-solution interface is investigated. A model reaction study is carried out to determine the binding kinetics diphenylchlorosilane to silica from carbon tetrachloride solution. The technique yields both in situ kinetic and structural information about the reaction of this reagent with silica surfaces.


Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 127 ◽  
Author(s):  
Yu Sun ◽  
Yazhen Wang ◽  
Li Liu ◽  
Tianyuan Xiao

A 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) acrylate, (6-oxidodibenzo [c,e][1,2] oxaphosphinin-6-yl) methyl acrylate (DOPOAA), has been prepared. Copolymers of styrene (St) and DOPOAA were prepared by emulsion polymerization. The chemical structures of copolymers containing levels of DOPOAA were verified using Fourier transform infrared (FT-IR) spectroscopy and 1H nuclear magnetic resonance (1H-NMR) spectroscopy. The thermal properties and flame-retardant behaviors of DOPO-containing monomers and copolymers were observed using thermogravimetric analysis and micro calorimetry tests. From thermogravimetric analysis (TGA), it was found out that the T5% for decomposition of the copolymer was lower than that of polystyrene (PS), but the residue at 700 °C was higher than that of PS. The results from micro calorimetry (MCC) tests indicated that the rate for the heat release of the copolymer combustion was lower than that for PS. The limiting oxygen index (LOI) for combustion of the copolymer rose with increasing levels of DOPOAA. These data indicate that copolymerization of the phosphorus-containing flame-retardant monomer, DOPOAA, into a PS segment can effectively improve the thermal stability and flame retardancy of the copolymer.


Author(s):  
Maciej Strzempek ◽  
Karolina A. Tarach ◽  
Kinga Góra-Marek ◽  
Fernando Rey ◽  
Miguel Palomino ◽  
...  

Abstract In this article the results of the statistical MC modelling corroborated by the FT-IR spectroscopy and gravimetric adsorption studies of the low aliphatic hydrocarbons in ZSM-5 (Si/Al =28 or...


2021 ◽  
Vol 22 (4) ◽  
pp. 2191
Author(s):  
Jing Huang ◽  
Nairveen Ali ◽  
Elsie Quansah ◽  
Shuxia Guo ◽  
Michel Noutsias ◽  
...  

In recent decades, vibrational spectroscopic methods such as Raman and FT-IR spectroscopy are widely applied to investigate plasma and serum samples. These methods are combined with drop coating deposition techniques to pre-concentrate the biomolecules in the dried droplet to improve the detected vibrational signal. However, most often encountered challenge is the inhomogeneous redistribution of biomolecules due to the coffee-ring effect. In this study, the variation in biomolecule distribution within the dried-sample droplet has been investigated using Raman and FT-IR spectroscopy and fluorescence lifetime imaging method. The plasma-sample from healthy donors were investigated to show the spectral differences between the inner and outer-ring region of the dried-sample droplet. Further, the preferred location of deposition of the most abundant protein albumin in the blood during the drying process of the plasma has been illustrated by using deuterated albumin. Subsequently, two patients with different cardiac-related diseases were investigated exemplarily to illustrate the variation in the pattern of plasma and serum biomolecule distribution during the drying process and its impact on patient-stratification. The study shows that a uniform sampling position of the droplet, both at the inner and the outer ring, is necessary for thorough clinical characterization of the patient’s plasma and serum sample using vibrational spectroscopy.


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