Daniel S. Raimundo

Anodic porous alumina structural characteristics study based on SEM image processing and analysis

The present work reports the porous alumina structures fabrication and their quantitative structural characteristics study based on mathematical morphology analysis by using the SEM images. The algorithm used in this work was implemented in 6.2 MATLAB software. Using the algorithm it was possible to obtain the distribution of maximum, minimum and average radius of the pores in porous alumina structures. Additionally, with the calculus of the area occupied by the pores, it was possible to obtain the porosity of the structures. The quantitative results could be obtained and related to the process fabrication characteristics, showing to be reliable and promising to be used to control the pores formation process. Then, this technique could provide a more accurate determination of pore sizes and pores distribution.

Self-assembled systems obtained by chemical and electrochemical techniques for photonic crystal fabrication

Abstract The present work reports the formation of self-assembled systems by chemical and electrochemical techniques for photonic crystal structures fabrication. The chemical technique was used to the fabrication of self-assembled polystyrene micro-spheres structures. The influence of temperature setup and monodispersion concentration in the chemical self-assemble mechanism was studied. The electrochemical technique also was used to fabricate the self-assembled porous alumina structures. The influence of electrolyte type and anodic voltage in the electrochemical self-assemble process was studied. The self-assembled structures were analyzed to the possibility of application as photonic crystal structures

Backside contact effect on the morphological and optical features of porous silicon photonic crystals

The present work reports on the effect of the type of backside contact used in the electrochemical process and their relation with the structural features and optical responses of the one-dimensional photonic crystal (PC) anodized in simple and double electrochemical cell. The PC, obtained in the single cell, showed to have thicker layers than of the PC obtained in double electrochemical cell. Additionally, the PC obtained in double cell showed highest reflectance in the band gap region than of the PCs obtained in single cell. These results suggest that the interface roughness between adjacent layers in the PC devices obtained in double electrochemical cell is minimized.