Journal De Physique Iii最新文献

{"title":"Mechanical Strength and Dislocation Velocities in GeSi Alloys","authors":"I. Yonenaga, K. Sumino","doi":"10.1051/JP3:1997264","DOIUrl":"https://doi.org/10.1051/JP3:1997264","url":null,"abstract":"The mechanical strength and dislocation velocities in single crystal Ge 1-x Si x alloys grown by the Czochralski method were investigated by compressive deformation and by the etch pit technique, respectively. In the temperature range 450-700°C and the stress range 3-20 MPa, the dislocation velocity in the GeSi with x = 0.004-0.022 decreases monotonically with an increase in the Si content, reaching about a half of that in Ge at x = 0.022, and can be expressed as a function of the stress and the temperature as expressed by the empirical equation known in other semiconductors. The yield stress of the GeSi alloy increases with increasing Si content from x = 0 to 0.4 and is temperature-insensitive at high temperatures, showing that the flow stress of alloy semiconductor has an athermal component which is absent in elemental or compound semiconductors. The hardening mechanism in alloy semiconductors is discussed.","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115433982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Étude théorique de matériaux bianisotropes synthétiques contrôlables","authors":"F. Auzanneau, Richard W. Ziolkowski","doi":"10.1051/JP3:1997267","DOIUrl":"https://doi.org/10.1051/JP3:1997267","url":null,"abstract":"Nous analysons les proprietes electromagnetiques de molecules composees de petites antennes reliees a un circuit electronique lineaire, plongees au sein d'un milieu hote. En fonction de la charge, nous retrouvons des modeles connus (Debye, Lorentz) et generalisons leurs proprietes (Time Derivative Debye et Lorentz). La dualite entre molecules dielectrique et magnetique permet de realiser des materiaux satisfaisant a E r = p r . Les proprietes des molecules bianisotropes, composees de deux antennes, obtenues par ce procede sont presentees. Enfin, l'application de lois de melange permet de specifier les proprietes globales du materiau composite final.","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128734400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of Atomic Fractions in Multi-Phased Materials of Limited Mass via an Empirical Approach to EXAFS Modeling","authors":"V. Harris, S. Oliver, J. D. Ayers, B. Das","doi":"10.1051/JP3:1997270","DOIUrl":"https://doi.org/10.1051/JP3:1997270","url":null,"abstract":"A least-square fitting analysis of EXAFS data collected from partially-crystallized Fe8uB2u thin films (t = 15 um)~ using data collected from pure phase standards of the crystalliza- tion products, was found effective in determining the relative atomic fraction of each crystalline phase present This fitting scheme provides a means for the quantitative treatment of crystall- lization and precipitation kinetics in thin films and multilayered structures A long standing limitation of extended X-ray absorption fine structure (EXAFS) as a tool for quantitative materials science has been its inability to measure the relative fraction of phases in multiphased materials. This is a prerequisite~ for example, in the study of crystallization and precipitation kinetics. Although there exist techniques which are able to perform these tasks on bulk materials, e.g. X-ray diffraction and digital scanning calorimetry~ recent trends toward the design and fabrication of low dimensional devices has made the study of thin films~ which cannot be readily measured by these techniques because of their small masses~ of particular importance. Of the popular local probes~ EXAFS is largely insensitive to small masses (lj, for example~ the signal-to-noise ratio of the EXAFS collected in total electron yield mode does not deteriorate appreciably for thin films until the sampled mass approaches Ge 10~~ grams. In an attempt to illustrate the usefulness of EXAFS in performing quantitative materials science we have applied EXAFS to study the crystallization of a model transition metal metalloid amorphous system in Fe-B. A least-square fitting analysis of the EXAFS data collected from partially-crystallized Fe-B thin films~ using data collected from pure phase standards of the crystallization products~ was found effective in determining the relative atomic fraction of each crystalline phase present. The samples used in this study are from a single 15 nm film (50 mm x 50 mm area) which was ion beam sputter-deposited from a pressed-powder target having the stoichiometry of Fe80B20. Individual pieces (7 mm x 7 mm) were encapsulated in evacuated glass ampoules and annealed at temperatures ranging from 473 K to 823 K for a period of 60 minutes. The X-ray absorption","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132704059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructures and Mechanical Properties of NiAl-(Cr) and TiAl-(Cr) Intermetallic Alloys","authors":"G. Frommeyer, C. Derder","doi":"10.1051/JP3:1997104","DOIUrl":"https://doi.org/10.1051/JP3:1997104","url":null,"abstract":"The oxidation resistant light weight aluminides: NiAl and TiAl with ordered B2 and L 10 super lattices show promising mechanical properties for high temperature applications. The ductility and strength properties at room and higher temperatures are strongly dependent upon the degree of ordering of the intermetallic compounds and of the microstructural parameters of the multiphase alloys, such as NiAl-(Cr) and TiAl-(Cr,Si). The presented paper describes and discusses the influence of second phases on the mechanical properties of these intermetallics with special emphasis of structural defects antistructure atoms - and the dislocation mobility.","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125556185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Large Impurity Atmospheres at Dislocations and Associated Point Defect Reactions in Differently n-Doped GaAs Crystals","authors":"C. Frigeri, J. Weyher, J. Jiménez, P. Martin","doi":"10.1051/JP3:1997263","DOIUrl":"https://doi.org/10.1051/JP3:1997263","url":null,"abstract":"The large impurity atmospheres at dislocations typical of n-type (Si- or Te-doped) GaAs crystals have been analysed by localized measurements of the free electron concentration, diffusion length and DSL etching velocity. The atmospheres always contain dopant atoms as well as point defects (complexes) whose formation and type depend on the type of dopant impurity and melt stoichiometry. The donor- or acceptor-like characteristics of such point defects (complexes) are responsible for the observed remarkable difference in the electrical and recombinative properties of the atmospheres between the differently doped crystals. The point defect reactions at the base of the formation of the slip traces are discussed. The possible mechanisms of the impurity-dislocation interaction leading to the formation of the atmospheres are also considered.","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128967045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trapping and recombination properties due to trap clustering","authors":"A. Mandowski, J. Świa̧tek","doi":"10.1051/JP3:1997258","DOIUrl":"https://doi.org/10.1051/JP3:1997258","url":null,"abstract":"Nonequilibrium charge carriers' trapping and recombination processes in semiconductors and insulators are studied by means of the Monte Carlo method. The effect of trap clustering on trapping and recombination kinetics is considered. It is shown that such non homogeneous distribution of traps may significantly change some physical properties of a solid. The phenomena are analysed wider various conditions. The influence of the temperature, the heating program and external electric field is studied. The calculations are performed for various trap parameters and various types of correlations between traps. Comparing isothermal and non isothermal spectra one can conclude that temperature dependent phenomena - such as thermoluminescence - are more sensitive to trap clustering than their isothermal counterparts -e.g. isothermal phosphorescence decay.","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130092026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TEM imaging of dislocation kinks, their motion and pinning","authors":"J. Spence, H. Kolar, H. Alexander","doi":"10.1051/JP3:1997262","DOIUrl":"https://doi.org/10.1051/JP3:1997262","url":null,"abstract":"HREM lattice images have been obtained using forbidden reflections generated by (111) stacking faults in silicon lying normal to the beam at temperatures up to 600 °C. Stationary and video images of 30°/90° partial dislocations relaxing toward equilibrium are studied. The lattice images formed from these forbidden reflections show directional fluctuations which are believed to be kinks, since, as expected from mobility measurements, a higher density is observed on 90° partials than on 30° partials, whereas artifacts contribute equally. Video difference images are used to obtain direct estimates of kink velocity. Observations of kink delay at obstacles, thought to be oxygen atoms at the dislocation core, yield unpinning energies and the parameters of the obstacle theory of kink motion. The kink formation energy is obtained from the distribution of kink pair separations in low-dose images. The kink migration rather than formation energy barrier is thus found to control the velocity of unobstructed dislocations in silicon under these experimental conditions.","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"87 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133587102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Une méthode naturelle de traitement des potentiels flottants associée a la méthode des élements finis","authors":"Patrick Dular, F. Henrotte, Benoît Meys, A. Genon, W. Legros","doi":"10.1051/JP3:1997252","DOIUrl":"https://doi.org/10.1051/JP3:1997252","url":null,"abstract":"Une methode efficace de traitement des potentiels flottants, utilisee dans le cadre de la methode des elements finis et appliquee au probleme de l'electrostatique, est presentee. De plus, cette methode conduit a une technique pour l'evaluation de la charge electrique, technique qui se base sur un calcul moyenne en accord parfait avec la formulation faible discretisee du probleme. La methode generale offre alors l'avantage de donner directement acces, lors du calcul, aux charges electriques totales des conducteurs a potentiels fixes ou flottants, tout en preservant le caractere symetrique de la matrice du systeme, ce qui permet un couplage aise entre charges et potentiels tant au niveau de la formulation qu'au niveau de la resolution. Elle permet ainsi d'aborder tout probleme electrostatique sans aucune technique intermediaire de calcul, par exemple de differentiation.","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115769999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CuAlSe2 Thin Films Obtained by Chalcogenization","authors":"S. Marsillac, K. Benchouk, C. E. Moctar, J. Bernède, J. Pouzet, A. Khellil, M. Jamali","doi":"10.1051/JP3:1997249","DOIUrl":"https://doi.org/10.1051/JP3:1997249","url":null,"abstract":"Abstract. CuAlSe2 thinfilms havebeen synthesizedbychalcogenization ofthin Cu and Al layerssequentiallydepositedbyevaporation under vacuum. Itisshownthat CuAlSe2films are obtained with some Cu2-rise andSe phases present at thesurfaceThese phases are suppressedbyannealing under vacuum and chemical etching in a KCNsolution. Attheendoftheprocess, XRDspectrum demonstratesthat textured CuAlSe2 filmshave been obtainedwith preferential orientationofthe crystallitesalong the (l12) direction. Thegapthefilmsis2.7eV as expected. The films are nearlystoichiometric~ but theirsurface is quiterough The XPSspectra show that some Nadiffusesfromthe substrate towardthesurface during the annealing process. However, this Nais etched by KCN.1. Introduction TernaryI-III-VI2chalcopyrite semiconductorshavereceivedconsiderableattentioninrecentyearsbecauseoftheir applications in photovoltaic devices.Ifthe CuInSe2 isthe most extensively studied compound of family, some other ternary chalcopyrites haveattractedmuchattention","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122768720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Caractérisation mécanique de micro-poutres par l'essai de flexion associé à une technique d'imagerie","authors":"A. Sergent, L. Robert, P. Delobelle, L. Bornier","doi":"10.1051/JP3:1997244","DOIUrl":"https://doi.org/10.1051/JP3:1997244","url":null,"abstract":"Durant cette derniere decennie le domaine des micro-techniques a connu un formidable essor et maintenant le dimensionnement des micro-systemes fait appel a de nombreuses disciplines scientifiques telles que l'electronique, les procedes d'obtention, l'optique, la mecanique... Celui-ci s'effectue le plus souvent de maniere globale et presente un caractere fortement interdisciplinaire. Dans ce contexte, la connaissance des proprietes mecaniques des materiaux utilises dans la conception des micro-systemes, fortement dependantes des procedes, est un aspect particulierement important. Dans cette logique, de nouveaux moyens experimentaux de caracterisation des materiaux en faibles dimensions ont ete realises et, parmi les differentes possibilites, on presente l'essai de flexion de micro-poutre encastree-encastree ou encastree-libre. La mesure des deplacements globaux est realisee simplement a l'aide d'une technique d'imagerie optique couplee a un traitement numerique d'images. Cette methode a ete validee sur des micro-poutres de silicium monocristallin et conduit a des mesures tres reproductibles. Une application sur des micro-poutres en nickel electro-depose et obtenues par technologie LIGA est egalement presentee. Les resultats experimentaux sont en bon accord avec ceux issus des calculs analytique et numerique, ce qui valide l'ensemble de l'experience.","PeriodicalId":237595,"journal":{"name":"Journal De Physique Iii","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114842441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}