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Porous anodic alumina (PAA) templates have been extensively studied due to their unique morphology and extensive applications.The fabrication of PAAcan bemodulated to achieve a self-ordered pore structure with desired pore size and interpore separation.PAAthin film templateswere fabricated fromsilicon doped aluminumfilm,Al-1wt%Si, based on one-step anodization method at 22 °C. Effects of anodizing potential (10–20V) as well as sulfuric acid concentrations (0.6–1.8M) on current density, interpore distance, anodization rate, and volume expansion were evaluated.The results indicated that current density increased largely exponentially with a concentration of the electrolyte at a given anodizing voltage. In addition, distinct andwell-ordered pores were obtained for anodization conducted at 15Vand 20 V. The volume expansion factor is proportional to the applied voltage. At 1.8Msulfuric acid, the expansion factor increases with pore regularity with 1.4 considered as the transition point.Theminimumcurrent density (2.1±0.15mAcm−2) was observed at theminimumanodizing condition (0.6M, 10V).Also,maximumanodizing condition (1.8M, 20V) resulted in the highest current density of 34±4mAcm−2.As expected, anodization time decreaseswith an increase in both anodization voltage and electrolyte concentration.

Porous anodic alumina (PAA) templates have been extensively studied due to their unique morphology and extensive applications.The fabrication of PAAcan bemodulated to achieve a self-ordered pore structure with desired pore size and interpore separation.PAAthin film templateswere fabricated fromsilicon doped aluminumfilm,Al-1wt%Si, based on one-step anodization method at 22 °C. Effects of anodizing potential (10–20V) as well as sulfuric acid concentrations (0.6–1.8M) on current density, interpore distance, anodization rate, and volume expansion were evaluated.The results indicated that current density increased largely exponentially with a concentration of the electrolyte at a given anodizing voltage. In addition, distinct andwell-ordered pores were obtained for anodization conducted at 15Vand 20 V. The volume expansion factor is proportional to the applied voltage. At 1.8Msulfuric acid, the expansion factor increases with pore regularity with 1.4 considered as the transition point.Theminimumcurrent density (2.1±0.15mAcm−2) was observed at theminimumanodizing condition (0.6M, 10V).Also,maximumanodizing condition (1.8M, 20V) resulted in the highest current density of 34±4mAcm−2.As expected, anodization time decreaseswith an increase in both anodization voltage and electrolyte concentration.

Porous anodic alumina (PAA) templates have been extensively studied due to their unique morphology and extensive applications.The fabrication of PAAcan bemodulated to achieve a self-ordered pore structure with desired pore size and interpore separation.PAAthin film templateswere fabricated fromsilicon doped aluminumfilm,Al-1wt%Si, based on one-step anodization method at 22 °C. Effects of anodizing potential (10–20V) as well as sulfuric acid concentrations (0.6–1.8M) on current density, interpore distance, anodization rate, and volume expansion were evaluated.The results indicated that current density increased largely exponentially with a concentration of the electrolyte at a given anodizing voltage. In addition, distinct andwell-ordered pores were obtained for anodization conducted at 15Vand 20 V. The volume expansion factor is proportional to the applied voltage. At 1.8Msulfuric acid, the expansion factor increases with pore regularity with 1.4 considered as the transition point.Theminimumcurrent density (2.1±0.15mAcm−2) was observed at theminimumanodizing condition (0.6M, 10V).Also,maximumanodizing condition (1.8M, 20V) resulted in the highest current density of 34±4mAcm−2.As expected, anodization time decreaseswith an increase in both anodization voltage and electrolyte concentration.

Porous anodic alumina (PAA) thin ¯lms, having interconnected pores, were fabricated from Cudoped aluminum ¯lms deposited on p-type silicon wafers by anodization. The anodization was done at four di®erent anodizing voltages (60 V, 70 V, 80V and 90 V) in phosphoric acid and two voltages (60V and 70 V) in oxalic acid. The aluminum and PAA samples were characterized by SEM and XRD while the pore arrangement, pore density, pore diameter, pore circularity and pore regularity were also analyzed. XRD spectra con¯rmed the aluminum to be crystalline with the dominant plane being (220), the Cu-rich phase have an average particle size of 15
5nm uniformly distributed within the Al matrix of 0.4-
m grain size. The steady-state current density through the anodization increased by 117% and 49% for oxalic and phosphoric acids, respectively, for 10V increase (from 60 to 70 V) in anodization voltage. Similarly, the etching rate increased by 100% for oxalic acid and by 40% for phosphoric acid which are responsible for 47% and 29% decreases in anodization duration, respectively. The highest value of circularity obtained for anodized Al–0.5wt.% Cu formed in oxalic acid at 60V was 0.86, and it was 0.80 for the phosphoric acid at 90 V. Anodization of Al–0.5wt.% Cu ¯lms allows the formation of circular pores directly on p-type silicon wafers which is of importance for future nanofabrication of advanced electronics. The results of anodized Al–0.5wt.% Cu thin ¯lm were compared with other anodized systems such as anodized pure Al and Al doped with Si.

Porous anodic alumina (PAA) thin ¯lms, having interconnected pores, were fabricated from Cudoped aluminum ¯lms deposited on p-type silicon wafers by anodization. The anodization was done at four di®erent anodizing voltages (60 V, 70 V, 80V and 90 V) in phosphoric acid and two voltages (60V and 70 V) in oxalic acid. The aluminum and PAA samples were characterized by SEM and XRD while the pore arrangement, pore density, pore diameter, pore circularity and pore regularity were also analyzed. XRD spectra con¯rmed the aluminum to be crystalline with the dominant plane being (220), the Cu-rich phase have an average particle size of 15
5nm uniformly distributed within the Al matrix of 0.4-
m grain size. The steady-state current density through the anodization increased by 117% and 49% for oxalic and phosphoric acids, respectively, for 10V increase (from 60 to 70 V) in anodization voltage. Similarly, the etching rate increased by 100% for oxalic acid and by 40% for phosphoric acid which are responsible for 47% and 29% decreases in anodization duration, respectively. The highest value of circularity obtained for anodized Al–0.5wt.% Cu formed in oxalic acid at 60V was 0.86, and it was 0.80 for the phosphoric acid at 90 V. Anodization of Al–0.5wt.% Cu ¯lms allows the formation of circular pores directly on p-type silicon wafers which is of importance for future nanofabrication of advanced electronics. The results of anodized Al–0.5wt.% Cu thin ¯lm were compared with other anodized systems such as anodized pure Al and Al doped with Si.

Ge-In-Se system, similar to many other chalcogenide glasses, has attracted much attention due to its interesting physical properties and applications. This article reports thermal analysis and estimation of activation energies of the glass transition and amorphous-crystallization transformation of Ge13In8Se79 chalcogenide glass. The kinetic parameters were investigated under a non-isothermal condition at different heating rates (7–40 K/min) using differential scanning calorimetric (DSC) technique. The amorphous nature of the samples was confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The activation energy was calculated from DSC data using five isoconversional methods: Kissinger–Akahira– Sunose (KAS), Flynn–Wall–Ozawa (FWO), Tang, Starink, and Vyazovkin. The results confirm that the activation energy of crystallization varies and depends on the degree of crystallization as well as temperature. It was also observed that the transformation from amorphous to the crystalline structure is complex involving different mechanisms of nucleation, diffusion, and growth.

Ge-In-Se system, similar to many other chalcogenide glasses, has attracted much attention due to its interesting physical properties and applications. This article reports thermal analysis and estimation of activation energies of the glass transition and amorphous-crystallization transformation of Ge13In8Se79 chalcogenide glass. The kinetic parameters were investigated under a non-isothermal condition at different heating rates (7–40 K/min) using differential scanning calorimetric (DSC) technique. The amorphous nature of the samples was confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The activation energy was calculated from DSC data using five isoconversional methods: Kissinger–Akahira– Sunose (KAS), Flynn–Wall–Ozawa (FWO), Tang, Starink, and Vyazovkin. The results confirm that the activation energy of crystallization varies and depends on the degree of crystallization as well as temperature. It was also observed that the transformation from amorphous to the crystalline structure is complex involving different mechanisms of nucleation, diffusion, and growth.

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