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Volumetric heat capacity enhancement in thin films of amorphous fluorocarbon polymers / Hongxiang Tian in Journal of heat transfer, Vol. 134 N° 8 (special issue) (Août 2012) 

Public ISBD [article]  in Journal of heat transfer > Vol. 134 N° 8 (special issue) (Août 2012) . - 09 p. Titre : Volumetric heat capacity enhancement in thin films of amorphous fluorocarbon polymers Type de document : texte imprimé Auteurs : Hongxiang Tian, Auteur ; Marc G. Ghossoub, Auteur ; Oksen T. Baris, Auteur Année de publication : 2012 Article en page(s) : 09 p. Note générale : heat transfer Langues : Anglais (eng) Mots-clés : thin  film;  differential  scanning  calorimetry;  heat  capacity;  fluorocarbon  polymer Index. décimale : 536 Chaleur. Thermodynamique Résumé : Plasma deposited amorphous fluorocarbon polymers find use in biopassivation, and as low-friction coatings, adhesion promoters, and interlayer dielectrics. Here, we exploit their ease of deposition into ultrathin layers (<50 nm thick) to explore their potential as thermal storage elements. We design and fabricate a microcalorimeter for measuring the heat capacity of thin fluorocarbons. Conventional thin film calorimetry assumes adiabatic conditions that lead to large errors as film thickness decreases. We propose a new data analysis procedure that incorporates a one-dimensional solution of the transient heat diffusion equation to account for conduction losses. The data for films with thicknesses in the range 12–27 nm reveal a lowering of the melting point and an increase in the volumetric heat capacity with decreasing thickness. We attribute this to change in the carbon to fluorine ratio in the films' composition. The volumetric heat capacity approximately doubles at room temperature as the film thickness decreases from 27 nm to 12 nm. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000008 [...] [article] Volumetric heat capacity enhancement in thin films of amorphous fluorocarbon polymers [texte imprimé] / Hongxiang Tian, Auteur ; Marc G. Ghossoub, Auteur ; Oksen T. Baris, Auteur . - 2012 . - 09 p. heat transfer Langues : Anglais (eng) in Journal of heat transfer > Vol. 134 N° 8 (special issue) (Août 2012) . - 09 p. Mots-clés : thin  film;  differential  scanning  calorimetry;  heat  capacity;  fluorocarbon  polymer Index. décimale : 536 Chaleur. Thermodynamique Résumé : Plasma deposited amorphous fluorocarbon polymers find use in biopassivation, and as low-friction coatings, adhesion promoters, and interlayer dielectrics. Here, we exploit their ease of deposition into ultrathin layers (<50 nm thick) to explore their potential as thermal storage elements. We design and fabricate a microcalorimeter for measuring the heat capacity of thin fluorocarbons. Conventional thin film calorimetry assumes adiabatic conditions that lead to large errors as film thickness decreases. We propose a new data analysis procedure that incorporates a one-dimensional solution of the transient heat diffusion equation to account for conduction losses. The data for films with thicknesses in the range 12–27 nm reveal a lowering of the melting point and an increase in the volumetric heat capacity with decreasing thickness. We attribute this to change in the carbon to fluorine ratio in the films' composition. The volumetric heat capacity approximately doubles at room temperature as the film thickness decreases from 27 nm to 12 nm. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000008 [...]