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http://archives.univ-biskra.dz/handle/123456789/7
2024-03-29T10:58:28ZStructural, optical and electrical properties of zinc oxide (ZnO) thin films deposited by a spray pyrolysis technique
http://archives.univ-biskra.dz/handle/123456789/8117
Titre: Structural, optical and electrical properties of zinc oxide (ZnO) thin films deposited by a spray pyrolysis technique
Auteur(s): Yacine Aoun; Boubaker Benhaoua; Brahim Gasmi; Said Benramache
Résumé: Zinc oxide (ZnO) thin films were deposited on glass substrates by spray pyrolysis technique decomposition
of zinc acetate dihydrate in an ethanol solution with 30 mL of deposition rate, the ZnO thin films were
deposited at two different temperatures: 300 and 350 C. The substrates were heated using the solar cells method.
The substrate was R217102 glass, whose size was 30 17.5 1 mm3. The films exhibit a hexagonal wurtzite
structure with a strong (002) preferred orientation. The higher value of crystallite size is attained for sprayed films
at 350 C, which is probably due to an improvement of the crystallinity of the films at this point.The average trans
mittance of obtain films is about 90%–95%, as measured by a UV–vis analyzer. The band gap energy varies from
3.265 to 3.294 eV for the deposited ZnO thin film at 300 and 350 C, respectively. The electrical resistivity measured
of our films in the order 0.36 cm.2016-09-24T00:00:00ZStudy the structural, optical and electrical properties of sprayed Zinc oxide (ZnO) thin films before and after annealing temperature
http://archives.univ-biskra.dz/handle/123456789/8116
Titre: Study the structural, optical and electrical properties of sprayed Zinc oxide (ZnO) thin films before and after annealing temperature
Auteur(s): Yacine Aoun; Boubaker Benhaoua; Brahim Gasmic; Said Benramache
Résumé: Zinc oxide (ZnO) thin films were deposited on glass substrates by spray pyrolysis technique by decomposition of
zinc acetate dihydrate in ethanol. The ZnO thin films were deposited at 350◦C and annealed at 500◦C for 2 h. The substrate
was R217102 glass in a size of 30 cm×7.5 cm×0.1 cm. The films exhibited a hexagonal wurtzite structure with a strong (002)
preferred orientation. The higher value of crystallite size (20.29 nm) was attained with films annealed at 500◦C, probably due
to improvement of the crystallinity of the films with heating. The average transmittance of the films, by UV-Vis, was over of
95 %. The band gap energy varied from 3.279 to 3.288 eV for the non-annealed and annealed films, respectively. The electrical
resistivity was measured to be 0.4 .cm.2016-09-24T00:00:00ZEffect of annealing temperature on structural, optical and electricalproperties of zinc oxide (ZnO) thin films deposited by spray pyrolysistechnique
http://archives.univ-biskra.dz/handle/123456789/8115
Titre: Effect of annealing temperature on structural, optical and electricalproperties of zinc oxide (ZnO) thin films deposited by spray pyrolysistechnique
Auteur(s): Yacine Aouna; Boubaker Benhaouac; Said Benramache; Brahim Gasmi
Résumé: tIn the present paper, the structural, optical and electrical properties of zinc oxide thin films were studiedbefore and after annealing temperature at 500◦C. The ZnO thin films were sprayed on glass substrates at350◦C, which were heated using the solar cells method. Polycrystalline films with a hexagonal wurtzitestructure with (0 0 2) preferential orientation corresponding to ZnO films were observed. It can be foundthat the good crystallinity are achieved in the films annealed at 500◦C. All films exhibit an average opticaltransmittance about 95% measured by UV–vis analyzer. The shift of optical transmittance towards highwavelength can be showed by the increases of band gap after annealing temperature which can be explainby the oxygen diffusion with annealing temperature. The electrical resistivity measured of our films inthe order 0.4 ( . cm).2016-09-24T00:00:00Zالسیاسة النقدیة خلال الأزمة المالیة العالمیة 2008 " FED و الاحتیاطي الفد ا رلي الأمریكي BCE " البنك المركزي الأوربي
http://archives.univ-biskra.dz/handle/123456789/8114
Titre: السیاسة النقدیة خلال الأزمة المالیة العالمیة 2008 " FED و الاحتیاطي الفد ا رلي الأمریكي BCE " البنك المركزي الأوربي
Auteur(s): أ/محمد الأمین ولید طالب
Résumé: La crise financière mondiale de 2008 a constitué un énorme défi pour la réserve fédérale américaine
et la banque centrale européenne. Ces deux institutions qui représentent l’autorité monétaire aux les
Etats-Unis et dans la zone euro ont essayé d’endiguer les conséquences de cette crise en utilisant les
politiques monétaires traditionnelles ainsi que le développement de nouveaux programmes.
La crise financière - la politique monétaire - la Réserve fédérale - la Banque centrale
européenne - liquidité2016-09-24T00:00:00Z