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In this work, GaSb thin films were prepared by DC magnetron sputtering method using Soda Lime-type glass and ITO (Indium tin oxide), as substrates. Annealing processes were carried out under high vacuum conditions to avoid the incorporation of oxygen (O) atoms present in the atmosphere. From X-ray diffraction (XRD) measurements it was possible to establish a Zinc-blende type structure and InO phases associated to the ITO substrate. The annealing processes showed a significant improvement in the crystallinity of the material being less amorphous when the annealing temperature (Tr) was 673 K. A value of the gap energy ranging from 0.75 to 0.85 eV was obtained in samples of GaSb when the Tr changed between 300 K and 673 K, respectively. Scanning Electron Microscopy (SEM) and atomic force microscopy (AFM) measurements provided information on the surface morphology of the material., Resumo Neste trabalho, os filmes finos de GaSb foram preparados pelo método de pulverização catódica assistido por campo magnético em substratos de vidro e ITO (óxido de estanho de índio). Após os processos de recozimento foram realizados em condições de alto vácuo que evitam a incorporação de átomos de oxigênio (O) presentes na atmosfera. A partir de medições de difração de raios X (XRD), foi possível estabelecer uma estrutura semelhante ao Zenz Blende e as fases InO associadas ao substrato ITO. Os processos de recozimento mostraram uma melhoria significativa na cristalinidade do material sendo menos amorfa quando a temperatura de recozimento (Tr) foi de 673 K. Foi obtido um valor do intervalo de energia proibido variando de 0,75 a 0,85 eV em amostras de GaSb quando o Tr mudou entre 300 K e 673 K, respectivamente. As medições de microscopia eletrônica de varredura (SEM) e microscopia de força atômica (AFM) forneceram informações sobre a morfologia da superfície do material., Resumen En este trabajo se fabricaron películas delgadas nanoestructuradas de GaSb por el método de pulverización catódica asistidas por campo magnético sobre sustratos de vidrio e ITO. Se realizaron procesos de recocido posterior a la preparación y bajo condiciones de alto vacío que evitaran la incorporación de átomos de oxígeno presentes en la atmósfera. A partir de medidas de difracción de rayos X se pudo establecer una estructura tipo blenda de Zinc y fases de InO asociadas al sustrato ITO. Los procesos de recocido permitieron evidenciar una mejora significativa en la cristalinidad del material siendo éste menos amorfo cuando la temperatura de recocido (Tr) fue de 673 K. Un valor de la brecha de energía prohibida variando entre 0.75 y 0.85 eV fue obtenido en muestras de GaSb cuando la Tr cambió entre 300 K y 673 K, respectivamente. Medidas de microscopia electrónica de barrido y fuerza atómica permitieron obtener información de la morfología en la superficie del material.

In this work, GaSb thin films were prepared by DC magnetron sputtering method using Soda Lime-type glass and ITO (Indium tin oxide), as substrates. Annealing processes were carried out under high vacuum conditions to avoid the incorporation of oxygen (O) atoms present in the atmosphere. From X-ray diffraction (XRD) measurements it was possible to establish a Zinc-blende type structure and InO phases associated to the ITO substrate. The annealing processes showed a significant improvement in the crystallinity of the material being less amorphous when the annealing temperature (Tr) was 673 K. A value of the gap energy ranging from 0.75 to 0.85 eV was obtained in samples of GaSb when the Tr changed between 300 K and 673 K, respectively. Scanning Electron Microscopy (SEM) and atomic force microscopy (AFM) measurements provided information on the surface morphology of the material., Resumo Neste trabalho, os filmes finos de GaSb foram preparados pelo método de pulverização catódica assistido por campo magnético em substratos de vidro e ITO (óxido de estanho de índio). Após os processos de recozimento foram realizados em condições de alto vácuo que evitam a incorporação de átomos de oxigênio (O) presentes na atmosfera. A partir de medições de difração de raios X (XRD), foi possível estabelecer uma estrutura semelhante ao Zenz Blende e as fases InO associadas ao substrato ITO. Os processos de recozimento mostraram uma melhoria significativa na cristalinidade do material sendo menos amorfa quando a temperatura de recozimento (Tr) foi de 673 K. Foi obtido um valor do intervalo de energia proibido variando de 0,75 a 0,85 eV em amostras de GaSb quando o Tr mudou entre 300 K e 673 K, respectivamente. As medições de microscopia eletrônica de varredura (SEM) e microscopia de força atômica (AFM) forneceram informações sobre a morfologia da superfície do material., Resumen En este trabajo se fabricaron películas delgadas nanoestructuradas de GaSb por el método de pulverización catódica asistidas por campo magnético sobre sustratos de vidrio e ITO. Se realizaron procesos de recocido posterior a la preparación y bajo condiciones de alto vacío que evitaran la incorporación de átomos de oxígeno presentes en la atmósfera. A partir de medidas de difracción de rayos X se pudo establecer una estructura tipo blenda de Zinc y fases de InO asociadas al sustrato ITO. Los procesos de recocido permitieron evidenciar una mejora significativa en la cristalinidad del material siendo éste menos amorfo cuando la temperatura de recocido (Tr) fue de 673 K. Un valor de la brecha de energía prohibida variando entre 0.75 y 0.85 eV fue obtenido en muestras de GaSb cuando la Tr cambió entre 300 K y 673 K, respectivamente. Medidas de microscopia electrónica de barrido y fuerza atómica permitieron obtener información de la morfología en la superficie del material.

Diamond-like carbon (DLC) has been widely studied due to its mechanical properties such as low friction coefficient, high hardness, and high adherence on different substrate materials. The unique combination of chemical and mechanical properties of DLC films has opened the possibilities for the electrochemical applications of these film materials. In this chapter, a review of DLC films with extremally high hardness and very resistant to corrosion by incoporating crystalline diamond (CD) particles during the deposition process will be presented. These films were for the first time developed in our laboratories and the characterization performed will be also showed. The studies carried out in our laboratories show CD-DLC films improving DLC and stainless steel electrochemical corrosion resistance. CD-DLC prevented aggressive ions from attacking metallic surfaces, becoming a potential candidate for an anti-corrosion material in industrial applications, like pipelines in petroleum industry. It was also investigated the influence of the diamond particle sizes on the electrochemical corrosion resistance of these films. The electrochemical parameters obtained from the potentiodynamic polarization curves and the impedance were correlationated with the qualitative sp3/sp2 ratio of the CD-DLC films obtained from Raman scattering spectroscopy. The results show that both protection efficiency and impedance increase with the decrease of ID/IG ratio. It means the increase of sp3 bonds in DLC films reduce its electrochemical corrosion, improving the electrochemical protection efficiency and the impedance. In addition, diamond crystallites bigger than the DLC grain size reduced the pitting corrosion, which is an indication of the chemical inertness of the CD-DLC coatings to the Cl− ions. The tribological behavior of these films under aggressive solution was also investigated. The presence of bigger CD particles increased the film roughness. In addition, these CD particles dem, isbn: 9781613247, Pages: xxx

Diamond-like carbon (DLC) has been widely studied due to its mechanical properties such as low friction coefficient, high hardness, and high adherence on different substrate materials. The unique combination of chemical and mechanical properties of DLC films has opened the possibilities for the electrochemical applications of these film materials. In this chapter, a review of DLC films with extremally high hardness and very resistant to corrosion by incoporating crystalline diamond (CD) particles during the deposition process will be presented. These films were for the first time developed in our laboratories and the characterization performed will be also showed. The studies carried out in our laboratories show CD-DLC films improving DLC and stainless steel electrochemical corrosion resistance. CD-DLC prevented aggressive ions from attacking metallic surfaces, becoming a potential candidate for an anti-corrosion material in industrial applications, like pipelines in petroleum industry. It was also investigated the influence of the diamond particle sizes on the electrochemical corrosion resistance of these films. The electrochemical parameters obtained from the potentiodynamic polarization curves and the impedance were correlationated with the qualitative sp3/sp2 ratio of the CD-DLC films obtained from Raman scattering spectroscopy. The results show that both protection efficiency and impedance increase with the decrease of ID/IG ratio. It means the increase of sp3 bonds in DLC films reduce its electrochemical corrosion, improving the electrochemical protection efficiency and the impedance. In addition, diamond crystallites bigger than the DLC grain size reduced the pitting corrosion, which is an indication of the chemical inertness of the CD-DLC coatings to the Cl− ions. The tribological behavior of these films under aggressive solution was also investigated. The presence of bigger CD particles increased the film roughness. In addition, these CD particles dem, Pages: xxx

Diamond-like carbon (DLC) has been widely studied due to its mechanical properties such as low friction coefficient, high hardness, and high adherence on different substrate materials. The unique combination of chemical and mechanical properties of DLC films has opened the possibilities for the electrochemical applications of these film materials. In this chapter, a review of DLC films with extremally high hardness and very resistant to corrosion by incoporating crystalline diamond (CD) particles during the deposition process will be presented. These films were for the first time developed in our laboratories and the characterization performed will be also showed. The studies carried out in our laboratories show CD-DLC films improving DLC and stainless steel electrochemical corrosion resistance. CD-DLC prevented aggressive ions from attacking metallic surfaces, becoming a potential candidate for an anti-corrosion material in industrial applications, like pipelines in petroleum industry. It was also investigated the influence of the diamond particle sizes on the electrochemical corrosion resistance of these films. The electrochemical parameters obtained from the potentiodynamic polarization curves and the impedance were correlationated with the qualitative sp3/sp2 ratio of the CD-DLC films obtained from Raman scattering spectroscopy. The results show that both protection efficiency and impedance increase with the decrease of ID/IG ratio. It means the increase of sp3 bonds in DLC films reduce its electrochemical corrosion, improving the electrochemical protection efficiency and the impedance. In addition, diamond crystallites bigger than the DLC grain size reduced the pitting corrosion, which is an indication of the chemical inertness of the CD-DLC coatings to the Cl− ions. The tribological behavior of these films under aggressive solution was also investigated. The presence of bigger CD particles increased the film roughness. In addition, these CD particles dem, Pages: xxx

Diamond-like carbon (DLC) has been widely studied due to its mechanical properties such as low friction coefficient, high hardness, and high adherence on different substrate materials. The unique combination of chemical and mechanical properties of DLC films has opened the possibilities for the electrochemical applications of these film materials. In this chapter, a review of DLC films with extremally high hardness and very resistant to corrosion by incoporating crystalline diamond (CD) particles during the deposition process will be presented. These films were for the first time developed in our laboratories and the characterization performed will be also showed. The studies carried out in our laboratories show CD-DLC films improving DLC and stainless steel electrochemical corrosion resistance. CD-DLC prevented aggressive ions from attacking metallic surfaces, becoming a potential candidate for an anti-corrosion material in industrial applications, like pipelines in petroleum industry. It was also investigated the influence of the diamond particle sizes on the electrochemical corrosion resistance of these films. The electrochemical parameters obtained from the potentiodynamic polarization curves and the impedance were correlationated with the qualitative sp3/sp2 ratio of the CD-DLC films obtained from Raman scattering spectroscopy. The results show that both protection efficiency and impedance increase with the decrease of ID/IG ratio. It means the increase of sp3 bonds in DLC films reduce its electrochemical corrosion, improving the electrochemical protection efficiency and the impedance. In addition, diamond crystallites bigger than the DLC grain size reduced the pitting corrosion, which is an indication of the chemical inertness of the CD-DLC coatings to the Cl− ions. The tribological behavior of these films under aggressive solution was also investigated. The presence of bigger CD particles increased the film roughness. In addition, these CD particles dem, isbn: 9781613247, Pages: xxx

Diamond-like carbon (DLC) has been widely studied due to its mechanical properties such as low friction coefficient, high hardness, and high adherence on different substrate materials. The unique combination of chemical and mechanical properties of DLC films has opened the possibilities for the electrochemical applications of these film materials. In this chapter, a review of DLC films with extremally high hardness and very resistant to corrosion by incoporating crystalline diamond (CD) particles during the deposition process will be presented. These films were for the first time developed in our laboratories and the characterization performed will be also showed. The studies carried out in our laboratories show CD-DLC films improving DLC and stainless steel electrochemical corrosion resistance. CD-DLC prevented aggressive ions from attacking metallic surfaces, becoming a potential candidate for an anti-corrosion material in industrial applications, like pipelines in petroleum industry. It was also investigated the influence of the diamond particle sizes on the electrochemical corrosion resistance of these films. The electrochemical parameters obtained from the potentiodynamic polarization curves and the impedance were correlationated with the qualitative sp3/sp2 ratio of the CD-DLC films obtained from Raman scattering spectroscopy. The results show that both protection efficiency and impedance increase with the decrease of ID/IG ratio. It means the increase of sp3 bonds in DLC films reduce its electrochemical corrosion, improving the electrochemical protection efficiency and the impedance. In addition, diamond crystallites bigger than the DLC grain size reduced the pitting corrosion, which is an indication of the chemical inertness of the CD-DLC coatings to the Cl− ions. The tribological behavior of these films under aggressive solution was also investigated. The presence of bigger CD particles increased the film roughness. In addition, these CD particles dem, isbn: 9781613247, Pages: xxx

Diamond-like carbon (DLC) has been widely studied due to its mechanical properties such as low friction coefficient, high hardness, and high adherence on different substrate materials. The unique combination of chemical and mechanical properties of DLC films has opened the possibilities for the electrochemical applications of these film materials. In this chapter, a review of DLC films with extremally high hardness and very resistant to corrosion by incoporating crystalline diamond (CD) particles during the deposition process will be presented. These films were for the first time developed in our laboratories and the characterization performed will be also showed. The studies carried out in our laboratories show CD-DLC films improving DLC and stainless steel electrochemical corrosion resistance. CD-DLC prevented aggressive ions from attacking metallic surfaces, becoming a potential candidate for an anti-corrosion material in industrial applications, like pipelines in petroleum industry. It was also investigated the influence of the diamond particle sizes on the electrochemical corrosion resistance of these films. The electrochemical parameters obtained from the potentiodynamic polarization curves and the impedance were correlationated with the qualitative sp3/sp2 ratio of the CD-DLC films obtained from Raman scattering spectroscopy. The results show that both protection efficiency and impedance increase with the decrease of ID/IG ratio. It means the increase of sp3 bonds in DLC films reduce its electrochemical corrosion, improving the electrochemical protection efficiency and the impedance. In addition, diamond crystallites bigger than the DLC grain size reduced the pitting corrosion, which is an indication of the chemical inertness of the CD-DLC coatings to the Cl− ions. The tribological behavior of these films under aggressive solution was also investigated. The presence of bigger CD particles increased the film roughness. In addition, these CD particles dem, isbn: 9781613247, Pages: xxx

Diamond-like carbon (DLC) has been widely studied due to its mechanical properties such as low friction coefficient, high hardness, and high adherence on different substrate materials. The unique combination of chemical and mechanical properties of DLC films has opened the possibilities for the electrochemical applications of these film materials. In this chapter, a review of DLC films with extremally high hardness and very resistant to corrosion by incoporating crystalline diamond (CD) particles during the deposition process will be presented. These films were for the first time developed in our laboratories and the characterization performed will be also showed. The studies carried out in our laboratories show CD-DLC films improving DLC and stainless steel electrochemical corrosion resistance. CD-DLC prevented aggressive ions from attacking metallic surfaces, becoming a potential candidate for an anti-corrosion material in industrial applications, like pipelines in petroleum industry. It was also investigated the influence of the diamond particle sizes on the electrochemical corrosion resistance of these films. The electrochemical parameters obtained from the potentiodynamic polarization curves and the impedance were correlationated with the qualitative sp3/sp2 ratio of the CD-DLC films obtained from Raman scattering spectroscopy. The results show that both protection efficiency and impedance increase with the decrease of ID/IG ratio. It means the increase of sp3 bonds in DLC films reduce its electrochemical corrosion, improving the electrochemical protection efficiency and the impedance. In addition, diamond crystallites bigger than the DLC grain size reduced the pitting corrosion, which is an indication of the chemical inertness of the CD-DLC coatings to the Cl− ions. The tribological behavior of these films under aggressive solution was also investigated. The presence of bigger CD particles increased the film roughness. In addition, these CD particles dem, isbn: 9781613247, Pages: xxx