http://archives.univ-biskra.dz/handle/123456789/2169 2026-04-12T17:44:27Z 2026-04-12T17:44:27Z Yacine Aoun Boubaker Benhaoua Brahim Gasmi Said Benramache http://archives.univ-biskra.dz/handle/123456789/8117 2019-05-06T09:41:17Z 2016-09-24T00:00:00Z

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.

2016-09-24T00:00:00Z Yacine Aoun Boubaker Benhaoua Brahim Gasmic Said Benramache http://archives.univ-biskra.dz/handle/123456789/8116 2019-05-06T09:38:41Z 2016-09-24T00:00:00Z

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.

2016-09-24T00:00:00Z Yacine Aouna Boubaker Benhaouac Said Benramache Brahim Gasmi http://archives.univ-biskra.dz/handle/123456789/8115 2019-05-06T09:43:13Z 2016-09-24T00:00:00Z

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).

2016-09-24T00:00:00Z أ/محمد الأمین ولید طالب http://archives.univ-biskra.dz/handle/123456789/8114 2019-05-06T09:41:13Z 2016-09-24T00:00:00Z

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 - liquidité

2016-09-24T00:00:00Z