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Efficient electrocatalysts are vital to large-current hydrogen production in commercial water splitting for green energy generation. Herein, a novel heterophase engineering strategy is described to produce polymorphic CoSe2 electrocatalysts. The composition of the electrocatalysts consisting of both cubic CoSe2 (c-CoSe2) and orthorhombic CoSe2 (o-CoSe2) phases can be controlled precisely. Our results demonstrate that junction-induced spin-state modulation of Co atoms enhances the adsorption of intermediates and accelerates charge transfer resulting in superior large-current hydrogen evolution reaction (HER) properties. Specifically, the CoSe2-based heterophase catalyst with the optimal c-CoSe2 content requires an overpotential of merely 240 mV to achieve 1,000 mA·cm−2 as well as a Tafel slope of 50.4 mV·dec−1. Furthermore, the electrocatalyst can maintain a large current density of 1,500 mA·cm−2 for over 320 h without decay. The results reveal the advantages and potential of heterophase junction engineering pertaining to design and fabrication of low-cost transition metal catalysts for large-current water splitting.

Microwave heating has been used to decrease the time required for exfoliation of thin single-crystalline silicon layers onto insulator substrates using ion-cut processing. Samples exfoliated in a 2.45 GHz, 1300 W cavity applicator microwave system saw a decrease in incubation times as compared to conventional anneal processes. Rutherford backscattering spectrometry, cross sectional scanning electron microscopy, cross sectional transmission electron microscopy, and selective aperture electron diffraction were used to determine the transferred layer thickness and crystalline quality. The surface quality was determined by atomic force microscopy. Hall measurements were used to determine electrical properties as a function of radiation repair anneal times. Results of physical and electrical characterizations demonstrate that the end products of microwave enhanced ion-cut processing do not appreciably differ from those using more traditional means of exfoliation. © 2007 American Institute of Physics.

Microwave heating has been used to decrease the time required for exfoliation of thin single-crystalline silicon layers onto insulator substrates using ion-cut processing. Samples exfoliated in a 2.45 GHz, 1300 W cavity applicator microwave system saw a decrease in incubation times as compared to conventional anneal processes. Rutherford backscattering spectrometry, cross sectional scanning electron microscopy, cross sectional transmission electron microscopy, and selective aperture electron diffraction were used to determine the transferred layer thickness and crystalline quality. The surface quality was determined by atomic force microscopy. Hall measurements were used to determine electrical properties as a function of radiation repair anneal times. Results of physical and electrical characterizations demonstrate that the end products of microwave enhanced ion-cut processing do not appreciably differ from those using more traditional means of exfoliation. © 2007 American Institute of Physics.

Amorphous carbon films have been applied in biomedical fields as potential biocompatible materials with wettability that can be adjusted by doping with other elements, including F, Si, Ti, O and N. In this study, nitrogen-doped hydrogenated amorphous carbon (a-C:H:N) films were deposited by PIII-D using C2H2 + N-2 gas mixtures. The biocompatibility and anti-thrombotic properties of the films were assessed in vitro. The surface morphology and surface wettability of the films were characterized using atomic force microscopy (AFM) and a contact angle method. The results show no cytotoxicity for all films, and films with appropriate nitrogen doping possess much better endothelial cell growth and anti-thrombotic properties. (c) 2005 Elsevier B.V. All rights reserved.

ZnO thin film with strong orientation (0 0 2) and smooth surface morphology was electrosynthesized on ITO-coated glass substrate at room temperature under pulsed voltage. Photoluminescence (PL) shows two obvious peaks: violet band and strong green band. The former is due to the free-excitonic transition and the latter is believed to arise from the single ionized oxygen vacancy (V-O(+)). Raman scattering reveals that the 580 cm(-1) mode and the shoulder peak mode at 550 cm(-1) originate from the N-related local vibration mode (LVM) and E-1 (LO) mode, respectively. (c) 2005 Elsevier B.V. All rights reserved.

Amorphous carbon films have been applied in biomedical fields as potential biocompatible materials with wettability that can be adjusted by doping with other elements, including F, Si, Ti, O and N. In this study, nitrogen-doped hydrogenated amorphous carbon (a-C:H:N) films were deposited by PIII-D using C2H2 + N-2 gas mixtures. The biocompatibility and anti-thrombotic properties of the films were assessed in vitro. The surface morphology and surface wettability of the films were characterized using atomic force microscopy (AFM) and a contact angle method. The results show no cytotoxicity for all films, and films with appropriate nitrogen doping possess much better endothelial cell growth and anti-thrombotic properties. (c) 2005 Elsevier B.V. All rights reserved.

ZnO thin film with strong orientation (0 0 2) and smooth surface morphology was electrosynthesized on ITO-coated glass substrate at room temperature under pulsed voltage. Photoluminescence (PL) shows two obvious peaks: violet band and strong green band. The former is due to the free-excitonic transition and the latter is believed to arise from the single ionized oxygen vacancy (V-O(+)). Raman scattering reveals that the 580 cm(-1) mode and the shoulder peak mode at 550 cm(-1) originate from the N-related local vibration mode (LVM) and E-1 (LO) mode, respectively. (c) 2005 Elsevier B.V. All rights reserved.

ZnO thin film with strong orientation (0 0 2) and smooth surface morphology was electrosynthesized on ITO-coated glass substrate at room temperature under pulsed voltage. Photoluminescence (PL) shows two obvious peaks: violet band and strong green band. The former is due to the free-excitonic transition and the latter is believed to arise from the single ionized oxygen vacancy (V-O(+)). Raman scattering reveals that the 580 cm(-1) mode and the shoulder peak mode at 550 cm(-1) originate from the N-related local vibration mode (LVM) and E-1 (LO) mode, respectively. (c) 2005 Elsevier B.V. All rights reserved.

Amorphous carbon films have been applied in biomedical fields as potential biocompatible materials with wettability that can be adjusted by doping with other elements, including F, Si, Ti, O and N. In this study, nitrogen-doped hydrogenated amorphous carbon (a-C:H:N) films were deposited by PIII-D using C2H2 + N-2 gas mixtures. The biocompatibility and anti-thrombotic properties of the films were assessed in vitro. The surface morphology and surface wettability of the films were characterized using atomic force microscopy (AFM) and a contact angle method. The results show no cytotoxicity for all films, and films with appropriate nitrogen doping possess much better endothelial cell growth and anti-thrombotic properties. (c) 2005 Elsevier B.V. All rights reserved.

The saturated vapor adsorption (SVA) method is adopted to fabricate nanorods, nanotubes, and special nanostructures with the assistance of template. Here, germanium tubular structures with several diameters (50-200 nm) were produced with porous anodic alumina (PAA) template via SVA. The germanium tubular structures grew inside the nanopores, whose size agreed with that of Ge nanotubes, and then expanded to outside of PAA template, forming pipette-like structures. The Ge tubular structure growth process can be explained by both the vapor-solid and oxide-assisted growth mechanisms, which is different from the mechanism for nanorod growth. (c) 2005 Elsevier B.V. All rights reserved.

The application of silicon-on-insulator (SOI) substrates to high-power integrated circuits is hampered by self-heating effects due to the poor thermal conductivity of the buried SiO2 layer. We propose to replace the buried SiO2 layer in SOI with a plasma synthesized SiOxNy, thin film to mitigate the self-heating effects. The SiOxNy films synthesized on silicon by plasma immersion ion implantation (PHI) exhibit outstanding surface topography, and excellent insulating characteristics are maintained up to an annealing temperature of 1100 degrees C. Hence, the polycrystallization in our SiOxNy materials is insignificant during conventional complementary metal oxide silicon (CMOS) processing. Using Si/SiOxNy direct bonding and the hydrogen-induced layer transfer, a silicon-on-SiOxNy structure has been successfully fabricated. Cross-sectional high-resolution transmission electron microscopy (HRTEM) and spreading resistance profiling (SRP) reveal that the bonded interface is abrupt and the top Si layer exhibits nearly perfect single crystalline quality. The reaction mechanism of SiOxNy and Si wafer bonding are also discussed. (c) 2004 Elsevier B.V. All rights reserved.

SiNx:H films with different N/Si ratios were synthesized by plasma-enhanced chemical vapor deposition (PECVD), aimed for BioMEMS or other biomedical applications. In vitro platelet adhesion tests were conducted to evaluate the hemocompatibility of the prepared films and the results were compared to low-temperature isotropic carbon (LTI-C) which is the most commonly used materials in commercial blood contacting biomedical devices such as artificial heart valves. Our results indicate that the SiN,:H films offer acceptable hemocompatibility compared to LTI-C and possess better characteristics. The hydrophilic property in terms of surface free energy is considered to contribute to the platelet adhesion and activation behavior. The thrombogenicity of the materials is investigated from the thermodynamic and kinetic points of view. Our results indicate that the Si-N bonds play a crucial role in determining the hydrophilic property of the film and consequently affect the blood/surface reactions and hemocompatibility of the films. (c) 2005 Elsevier B.V. All rights reserved.

A large quantity of monocrystalline germanium nanorods and their arrays were produced on a porous anodic alumina (PAA) template utilizing saturated vapor adsorption, during which the Ge gas pressure was saturated at a high temperature in an airtight quartz tube. Raman scattering and photoluminescence (PL) results were acquired from the Ge nanorod array and discussed in details. Using Si-based PAA template with 25 nm nanopores, Si-based Ge nanorod array with a large area (larger than 1x1 cm(2)) was obtained and the quantum confinement effect is demonstrated in Raman spectrum. (C) 2005 American Institute of Physics.

We report on cathodoluminescence (CL) of monosized and well-aligned 4 angstrom single-walled carbon nanotubes in a zeolite template (AlPO4-5 single crystal). The CL exhibits three emission bands centered at 1.87, 2.22, and 2.98 eV, which are assigned to three possible 4 angstrom tube structures (4,2), (5,0), and (3,3), respectively. The assignation is based on first-principles calculations, Raman scattering measurement, and CL behavior of various samples. The emission peak shift of the (5, 0) tube is explained by the transition mechanism being different from photoluminescence due to the excitation of electrons with high energy. (c) 2005 American Institute of Physics.

A large quantity of monocrystalline germanium nanorods and their arrays were produced on a porous anodic alumina (PAA) template utilizing saturated vapor adsorption, during which the Ge gas pressure was saturated at a high temperature in an airtight quartz tube. Raman scattering and photoluminescence (PL) results were acquired from the Ge nanorod array and discussed in details. Using Si-based PAA template with 25 nm nanopores, Si-based Ge nanorod array with a large area (larger than 1x1 cm(2)) was obtained and the quantum confinement effect is demonstrated in Raman spectrum. (C) 2005 American Institute of Physics.

We report on cathodoluminescence (CL) of monosized and well-aligned 4 angstrom single-walled carbon nanotubes in a zeolite template (AlPO4-5 single crystal). The CL exhibits three emission bands centered at 1.87, 2.22, and 2.98 eV, which are assigned to three possible 4 angstrom tube structures (4,2), (5,0), and (3,3), respectively. The assignation is based on first-principles calculations, Raman scattering measurement, and CL behavior of various samples. The emission peak shift of the (5, 0) tube is explained by the transition mechanism being different from photoluminescence due to the excitation of electrons with high energy. (c) 2005 American Institute of Physics.

The application of silicon-on-insulator (SOI) substrates to high-power integrated circuits is hampered by self-heating effects due to the poor thermal conductivity of the buried SiO2 layer. We propose to replace the buried SiO2 layer in SOI with a plasma synthesized SiOxNy, thin film to mitigate the self-heating effects. The SiOxNy films synthesized on silicon by plasma immersion ion implantation (PHI) exhibit outstanding surface topography, and excellent insulating characteristics are maintained up to an annealing temperature of 1100 degrees C. Hence, the polycrystallization in our SiOxNy materials is insignificant during conventional complementary metal oxide silicon (CMOS) processing. Using Si/SiOxNy direct bonding and the hydrogen-induced layer transfer, a silicon-on-SiOxNy structure has been successfully fabricated. Cross-sectional high-resolution transmission electron microscopy (HRTEM) and spreading resistance profiling (SRP) reveal that the bonded interface is abrupt and the top Si layer exhibits nearly perfect single crystalline quality. The reaction mechanism of SiOxNy and Si wafer bonding are also discussed. (c) 2004 Elsevier B.V. All rights reserved.

SiNx:H films with different N/Si ratios were synthesized by plasma-enhanced chemical vapor deposition (PECVD), aimed for BioMEMS or other biomedical applications. In vitro platelet adhesion tests were conducted to evaluate the hemocompatibility of the prepared films and the results were compared to low-temperature isotropic carbon (LTI-C) which is the most commonly used materials in commercial blood contacting biomedical devices such as artificial heart valves. Our results indicate that the SiN,:H films offer acceptable hemocompatibility compared to LTI-C and possess better characteristics. The hydrophilic property in terms of surface free energy is considered to contribute to the platelet adhesion and activation behavior. The thrombogenicity of the materials is investigated from the thermodynamic and kinetic points of view. Our results indicate that the Si-N bonds play a crucial role in determining the hydrophilic property of the film and consequently affect the blood/surface reactions and hemocompatibility of the films. (c) 2005 Elsevier B.V. All rights reserved.

The saturated vapor adsorption (SVA) method is adopted to fabricate nanorods, nanotubes, and special nanostructures with the assistance of template. Here, germanium tubular structures with several diameters (50-200 nm) were produced with porous anodic alumina (PAA) template via SVA. The germanium tubular structures grew inside the nanopores, whose size agreed with that of Ge nanotubes, and then expanded to outside of PAA template, forming pipette-like structures. The Ge tubular structure growth process can be explained by both the vapor-solid and oxide-assisted growth mechanisms, which is different from the mechanism for nanorod growth. (c) 2005 Elsevier B.V. All rights reserved.

Hydrogen ion implantation is conventionally used to initiate the transfer of Si thin layers onto Si wafers coated with thermal oxide. In this work, we studied the feasibility of using plasma hydrogenation to replace high dose H implantation for layer transfer. Boron ion implantation was used to introduce H -trapping centers into Si wafers to illustrate the idea. Instead of the widely recognized interactions between boron and hydrogen atoms, this study showed that lattice damage, i.e., dangling bonds, traps H atoms and can lead to surface blistering during hydrogenation or upon postannealing at higher temperature. The B implantation and subsequent processes control the uniformity of H trapping and the trap depths. While the trap centers were introduced by B implantation in this study, there are many other means to do the same without implantation. Our results suggest an innovative way to achieve high quality transfer of Si layers without H implantation at high energies and high doses. © 2005 American Institute of Physics.

We have developed an innovative approach without the use of ion implantation to transfer a high-quality thin Si layer for the fabrication of silicon-on-insulator wafers. The technique uses a buried strained SiGe layer, a few nanometers in thickness, to provide H trapping centers. In conjunction with H plasma hydrogenation, lift-off of the top Si layer can be realized with cleavage occurring at the depth of the strained SiGe layer. This technique avoids irradiation damage within the top Si layer that typically results from ion implantation used to create H trapping regions in the conventional ion-cut method. We explain the strain-facilitated layer transfer as being due to preferential vacancy aggregation within the strained layer and subsequent trapping of hydrogen, which lead to cracking in a well controlled manner. © 2005 American Institute of Physics.

Hydrogen ion implantation is conventionally used to initiate the transfer of Si thin layers onto Si wafers coated with thermal oxide. In this work, we studied the feasibility of using plasma hydrogenation to replace high dose H implantation for layer transfer. Boron ion implantation was used to introduce H -trapping centers into Si wafers to illustrate the idea. Instead of the widely recognized interactions between boron and hydrogen atoms, this study showed that lattice damage, i.e., dangling bonds, traps H atoms and can lead to surface blistering during hydrogenation or upon postannealing at higher temperature. The B implantation and subsequent processes control the uniformity of H trapping and the trap depths. While the trap centers were introduced by B implantation in this study, there are many other means to do the same without implantation. Our results suggest an innovative way to achieve high quality transfer of Si layers without H implantation at high energies and high doses. © 2005 American Institute of Physics.

We have developed an innovative approach without the use of ion implantation to transfer a high-quality thin Si layer for the fabrication of silicon-on-insulator wafers. The technique uses a buried strained SiGe layer, a few nanometers in thickness, to provide H trapping centers. In conjunction with H plasma hydrogenation, lift-off of the top Si layer can be realized with cleavage occurring at the depth of the strained SiGe layer. This technique avoids irradiation damage within the top Si layer that typically results from ion implantation used to create H trapping regions in the conventional ion-cut method. We explain the strain-facilitated layer transfer as being due to preferential vacancy aggregation within the strained layer and subsequent trapping of hydrogen, which lead to cracking in a well controlled manner. © 2005 American Institute of Physics.

SiNx:H films with different N/Si ratios were synthesized by plasma-enhanced chemical vapor deposition (PECVD), aimed for BioMEMS or other biomedical applications. In vitro platelet adhesion tests were conducted to evaluate the hemocompatibility of the prepared films and the results were compared to low-temperature isotropic carbon (LTI-C) which is the most commonly used materials in commercial blood contacting biomedical devices such as artificial heart valves. Our results indicate that the SiN,:H films offer acceptable hemocompatibility compared to LTI-C and possess better characteristics. The hydrophilic property in terms of surface free energy is considered to contribute to the platelet adhesion and activation behavior. The thrombogenicity of the materials is investigated from the thermodynamic and kinetic points of view. Our results indicate that the Si-N bonds play a crucial role in determining the hydrophilic property of the film and consequently affect the blood/surface reactions and hemocompatibility of the films. (c) 2005 Elsevier B.V. All rights reserved.

We report on cathodoluminescence (CL) of monosized and well-aligned 4 angstrom single-walled carbon nanotubes in a zeolite template (AlPO4-5 single crystal). The CL exhibits three emission bands centered at 1.87, 2.22, and 2.98 eV, which are assigned to three possible 4 angstrom tube structures (4,2), (5,0), and (3,3), respectively. The assignation is based on first-principles calculations, Raman scattering measurement, and CL behavior of various samples. The emission peak shift of the (5, 0) tube is explained by the transition mechanism being different from photoluminescence due to the excitation of electrons with high energy. (c) 2005 American Institute of Physics.

The application of silicon-on-insulator (SOI) substrates to high-power integrated circuits is hampered by self-heating effects due to the poor thermal conductivity of the buried SiO2 layer. We propose to replace the buried SiO2 layer in SOI with a plasma synthesized SiOxNy, thin film to mitigate the self-heating effects. The SiOxNy films synthesized on silicon by plasma immersion ion implantation (PHI) exhibit outstanding surface topography, and excellent insulating characteristics are maintained up to an annealing temperature of 1100 degrees C. Hence, the polycrystallization in our SiOxNy materials is insignificant during conventional complementary metal oxide silicon (CMOS) processing. Using Si/SiOxNy direct bonding and the hydrogen-induced layer transfer, a silicon-on-SiOxNy structure has been successfully fabricated. Cross-sectional high-resolution transmission electron microscopy (HRTEM) and spreading resistance profiling (SRP) reveal that the bonded interface is abrupt and the top Si layer exhibits nearly perfect single crystalline quality. The reaction mechanism of SiOxNy and Si wafer bonding are also discussed. (c) 2004 Elsevier B.V. All rights reserved.

The saturated vapor adsorption (SVA) method is adopted to fabricate nanorods, nanotubes, and special nanostructures with the assistance of template. Here, germanium tubular structures with several diameters (50-200 nm) were produced with porous anodic alumina (PAA) template via SVA. The germanium tubular structures grew inside the nanopores, whose size agreed with that of Ge nanotubes, and then expanded to outside of PAA template, forming pipette-like structures. The Ge tubular structure growth process can be explained by both the vapor-solid and oxide-assisted growth mechanisms, which is different from the mechanism for nanorod growth. (c) 2005 Elsevier B.V. All rights reserved.

A large quantity of monocrystalline germanium nanorods and their arrays were produced on a porous anodic alumina (PAA) template utilizing saturated vapor adsorption, during which the Ge gas pressure was saturated at a high temperature in an airtight quartz tube. Raman scattering and photoluminescence (PL) results were acquired from the Ge nanorod array and discussed in details. Using Si-based PAA template with 25 nm nanopores, Si-based Ge nanorod array with a large area (larger than 1x1 cm(2)) was obtained and the quantum confinement effect is demonstrated in Raman spectrum. (C) 2005 American Institute of Physics.

Si-based nano-island arrays were fabricated on porous anodic alumina by two methods. In the first method, a thick silicon film was first deposited onto the surface with highly ordered bowl array prepared by anodizing an Al foil, followed by the formation of a polycrystalline silicon nano-island array on the surface close to the bowl array after dissolving aluminum. In the second method, porous anodization was performed on an Al thin film on Si and a SiO2 nano-island array was subsequently formed electrochemically. Time-resolved atomic force microscopy and photoluminescence were used to investigate the growth process as well as the mechanism of the growth process. Our proposed mechanism as well as assumptions made to formulate the model were found to be in agreement with the experimental results. (C) 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

High-quality (100) ZnO films with smooth surface topography have been synthesized on Si substrate by plasma immersion ion implantation. The materials exhibit compressive stress because of room temperature growth. After annealing at different temperatures, various visible photoluminescence bands are observed. The optical phenomenon as well as the transition mechanism which may involve defects such as [Zn-1], [V-Zn], and [O-i(-)] induced by the high substrate bias are discussed in this paper. (C) 2004 Elsevier Ltd. All rights reserved.

We propose to replace the buried SiO2 layer in silicon-on-insulator with a plasma synthesized diamond-like-carbon (DLC) thin film to mitigate the self-heating effects. The DLC films synthesized on silicon by a plasma immersion ion implantation & deposition process exhibit outstanding surface topography, and excellent insulating properties are maintained up to an annealing temperature of 900degreesC. Hence, the degree of graphitization in our DLC materials is insignificant during thin-film transistor processing and even in most annealing steps in conventional complementary metal oxide silicon processing. Using Si/DLC direct bonding and the hydrogen-induced layer transfer method, a silicon-on-diamond structure has been fabricated. Cross-sectional high-resolution transmission electron microscopy reveals that the bonded interface is abrupt and the top Si layer exhibits nearly perfect single crystalline quality. A model is postulated to describe the reactions occurring at the interface during the annealing steps in Si-DLC wafer bonding. (C) American Institute of Physics.

High-quality (100) ZnO films with smooth surface topography have been synthesized on Si substrate by plasma immersion ion implantation. The materials exhibit compressive stress because of room temperature growth. After annealing at different temperatures, various visible photoluminescence bands are observed. The optical phenomenon as well as the transition mechanism which may involve defects such as [Zn-1], [V-Zn], and [O-i(-)] induced by the high substrate bias are discussed in this paper. (C) 2004 Elsevier Ltd. All rights reserved.

We propose to replace the buried SiO2 layer in silicon-on-insulator with a plasma synthesized diamond-like-carbon (DLC) thin film to mitigate the self-heating effects. The DLC films synthesized on silicon by a plasma immersion ion implantation & deposition process exhibit outstanding surface topography, and excellent insulating properties are maintained up to an annealing temperature of 900degreesC. Hence, the degree of graphitization in our DLC materials is insignificant during thin-film transistor processing and even in most annealing steps in conventional complementary metal oxide silicon processing. Using Si/DLC direct bonding and the hydrogen-induced layer transfer method, a silicon-on-diamond structure has been fabricated. Cross-sectional high-resolution transmission electron microscopy reveals that the bonded interface is abrupt and the top Si layer exhibits nearly perfect single crystalline quality. A model is postulated to describe the reactions occurring at the interface during the annealing steps in Si-DLC wafer bonding. (C) American Institute of Physics.

We propose to replace the buried SiO2 layer in silicon-on-insulator with a plasma synthesized diamond-like-carbon (DLC) thin film to mitigate the self-heating effects. The DLC films synthesized on silicon by a plasma immersion ion implantation & deposition process exhibit outstanding surface topography, and excellent insulating properties are maintained up to an annealing temperature of 900degreesC. Hence, the degree of graphitization in our DLC materials is insignificant during thin-film transistor processing and even in most annealing steps in conventional complementary metal oxide silicon processing. Using Si/DLC direct bonding and the hydrogen-induced layer transfer method, a silicon-on-diamond structure has been fabricated. Cross-sectional high-resolution transmission electron microscopy reveals that the bonded interface is abrupt and the top Si layer exhibits nearly perfect single crystalline quality. A model is postulated to describe the reactions occurring at the interface during the annealing steps in Si-DLC wafer bonding. (C) American Institute of Physics.

Si-based nano-island arrays were fabricated on porous anodic alumina by two methods. In the first method, a thick silicon film was first deposited onto the surface with highly ordered bowl array prepared by anodizing an Al foil, followed by the formation of a polycrystalline silicon nano-island array on the surface close to the bowl array after dissolving aluminum. In the second method, porous anodization was performed on an Al thin film on Si and a SiO2 nano-island array was subsequently formed electrochemically. Time-resolved atomic force microscopy and photoluminescence were used to investigate the growth process as well as the mechanism of the growth process. Our proposed mechanism as well as assumptions made to formulate the model were found to be in agreement with the experimental results. (C) 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

High-quality (100) ZnO films with smooth surface topography have been synthesized on Si substrate by plasma immersion ion implantation. The materials exhibit compressive stress because of room temperature growth. After annealing at different temperatures, various visible photoluminescence bands are observed. The optical phenomenon as well as the transition mechanism which may involve defects such as [Zn-1], [V-Zn], and [O-i(-)] induced by the high substrate bias are discussed in this paper. (C) 2004 Elsevier Ltd. All rights reserved.

Epitaxial growth of CoSi2 by solid state reaction of Co/a-Si/Ti/Si(100) is investigated. A Ti/a-Si composite interlayer is used to modify the diffusion barrier and influence the epitaxial growth process. The epitaxial quality of the CoSi2 is improved compared to the film grown by Co/Ti/Si reaction. A multielement amorphous layer is formed by a solid-state amorphization reaction at the initial stage of the multilayer reaction. This layer acts as a diffusion barrier, which controls the atomic interdiffusion of Co and Si while limiting the supply of Co atoms. CoSi2 grows as the first phase and the growth interface of the epitaxial CoSi2 is at both the CoSi2/Si and CoSi2/CoSi interfaces. Investigation of the growth kinetics shows that the activation energy of CoSi2 formation is larger than that without an amorphous Si layer. (C) 2001 American Institute of Physics.

A study has been made of the interlaminar fracture behaviour of unidirectional carbon fibre-epoxy matrix composites containing polyethylene terephthalate (PET) interleaving films,with and without plasma surface treatment. Comparisons are made of the initiation Values of mode I and mode II interlaminar fracture toughness, G(Ic) and G(IIc), for composites with and without interleaves. It is shown that the interleaves have completely reverse effects on interlaminar fracture toughness with different mo des of fracture. The interleaves have the detrimental effect of reducing G(Ic), up to 70\%, and the plasma treatment is effective in mitigating the toughness reduction. In sharp contrast, the interleaves improve the corresponding toughness in mode II, with a negligible influence of plasma treatment on G(IIc). The major failure mechanisms associated with the presence of interleaves are discussed.

Epitaxial growth of CoSi2 by solid state reaction of Co/a-Si/Ti/Si(100) is investigated. A Ti/a-Si composite interlayer is used to modify the diffusion barrier and influence the epitaxial growth process. The epitaxial quality of the CoSi2 is improved compared to the film grown by Co/Ti/Si reaction. A multielement amorphous layer is formed by a solid-state amorphization reaction at the initial stage of the multilayer reaction. This layer acts as a diffusion barrier, which controls the atomic interdiffusion of Co and Si while limiting the supply of Co atoms. CoSi2 grows as the first phase and the growth interface of the epitaxial CoSi2 is at both the CoSi2/Si and CoSi2/CoSi interfaces. Investigation of the growth kinetics shows that the activation energy of CoSi2 formation is larger than that without an amorphous Si layer. (C) 2001 American Institute of Physics.

A study has been made of the interlaminar fracture behaviour of unidirectional carbon fibre-epoxy matrix composites containing polyethylene terephthalate (PET) interleaving films,with and without plasma surface treatment. Comparisons are made of the initiation Values of mode I and mode II interlaminar fracture toughness, G(Ic) and G(IIc), for composites with and without interleaves. It is shown that the interleaves have completely reverse effects on interlaminar fracture toughness with different mo des of fracture. The interleaves have the detrimental effect of reducing G(Ic), up to 70\%, and the plasma treatment is effective in mitigating the toughness reduction. In sharp contrast, the interleaves improve the corresponding toughness in mode II, with a negligible influence of plasma treatment on G(IIc). The major failure mechanisms associated with the presence of interleaves are discussed.

Epitaxial growth of CoSi2 by solid state reaction of Co/a-Si/Ti/Si(100) is investigated. A Ti/a-Si composite interlayer is used to modify the diffusion barrier and influence the epitaxial growth process. The epitaxial quality of the CoSi2 is improved compared to the film grown by Co/Ti/Si reaction. A multielement amorphous layer is formed by a solid-state amorphization reaction at the initial stage of the multilayer reaction. This layer acts as a diffusion barrier, which controls the atomic interdiffusion of Co and Si while limiting the supply of Co atoms. CoSi2 grows as the first phase and the growth interface of the epitaxial CoSi2 is at both the CoSi2/Si and CoSi2/CoSi interfaces. Investigation of the growth kinetics shows that the activation energy of CoSi2 formation is larger than that without an amorphous Si layer. (C) 2001 American Institute of Physics.

A study has been made of the interlaminar fracture behaviour of unidirectional carbon fibre-epoxy matrix composites containing polyethylene terephthalate (PET) interleaving films,with and without plasma surface treatment. Comparisons are made of the initiation Values of mode I and mode II interlaminar fracture toughness, G(Ic) and G(IIc), for composites with and without interleaves. It is shown that the interleaves have completely reverse effects on interlaminar fracture toughness with different mo des of fracture. The interleaves have the detrimental effect of reducing G(Ic), up to 70\%, and the plasma treatment is effective in mitigating the toughness reduction. In sharp contrast, the interleaves improve the corresponding toughness in mode II, with a negligible influence of plasma treatment on G(IIc). The major failure mechanisms associated with the presence of interleaves are discussed.

Plasma immersion ion implantation is a burgeoning surface modification technique and not limited by the line-of-sight restriction plaguing conventional beam-line ion implantation. It is therefore an excellent technique to treat interior surfaces as well as components of a complex shape. To enhance the implant uniformity and increase the thickness of the modified layer, we are using a high frequency, low-voltage process to achieve high temperature and dose rate to increase the thickness of the modified layer. The low voltage conditions also lead to a thinner sheath more favorable to conformal implantation. In this article, we will describe our special modulator consisting of a single ended forward converter with a step-up transformer. The modulator is designed to operate from 5 to 35 kHz and the output voltage is adjustable to an upper ceiling of 5000 V that is deliberately chosen to be our voltage limit for the present experiments. We will also present experimental data on SS304 stainless steel materials elucidating the advantages of our modulator and high frequency, low-voltage experimental protocols. (C) 1999 American Institute of Physics. [S0034-6748(99)00803-5].

Plasma immersion ion implantation is a burgeoning surface modification technique and not limited by the line-of-sight restriction plaguing conventional beam-line ion implantation. It is therefore an excellent technique to treat interior surfaces as well as components of a complex shape. To enhance the implant uniformity and increase the thickness of the modified layer, we are using a high frequency, low-voltage process to achieve high temperature and dose rate to increase the thickness of the modified layer. The low voltage conditions also lead to a thinner sheath more favorable to conformal implantation. In this article, we will describe our special modulator consisting of a single ended forward converter with a step-up transformer. The modulator is designed to operate from 5 to 35 kHz and the output voltage is adjustable to an upper ceiling of 5000 V that is deliberately chosen to be our voltage limit for the present experiments. We will also present experimental data on SS304 stainless steel materials elucidating the advantages of our modulator and high frequency, low-voltage experimental protocols. (C) 1999 American Institute of Physics. [S0034-6748(99)00803-5].

Plasma immersion ion implantation (PIII) has recently been shown to be a viable method to fabricate silicon-on-insulator (SOI) materials using either the SPIMOX (separation by plasma implantation of oxygen) or the ion cut/wafer bonding method, We have recently modified and characterized a new generation plasma immersion ion implanter for SOI fabrication, and this paper will discuss some of the instrumental and processing issues, including the plasma source, mean free path consideration, and de sheath characteristics.

The high voltage and electromagnetic field environment poses a big challenge to a control system for plasma immersion ion implantation (PIII). The automation process must be immune to electric field interference produced by the high voltage power supply, modulator, radio-frequency or microwave plasma generator, MEVVA plasma sources, and so oil. We have recently designed and installed a distributed control system, PIIIDCS, to automate the operation of our PIII facility. Programmable logic controllers are used as the held control stations because of their good anti-interference ability and good real time response. A DH-485 network is used as the communication link between the field controllers and the management station in order to improve the robustness and reliability of the system. The newly developed interface is designed to work in a graphic mode in Microsoft Windows 95. Test runs have shown that the system is reliable, flexible, and easy to operate. The development of this novel control system will expedite the development of commercial PIII instrumentation. (C) 1998 American Institute of Physics.

The high voltage and electromagnetic field environment poses a big challenge to a control system for plasma immersion ion implantation (PIII). The automation process must be immune to electric field interference produced by the high voltage power supply, modulator, radio-frequency or microwave plasma generator, MEVVA plasma sources, and so oil. We have recently designed and installed a distributed control system, PIIIDCS, to automate the operation of our PIII facility. Programmable logic controllers are used as the held control stations because of their good anti-interference ability and good real time response. A DH-485 network is used as the communication link between the field controllers and the management station in order to improve the robustness and reliability of the system. The newly developed interface is designed to work in a graphic mode in Microsoft Windows 95. Test runs have shown that the system is reliable, flexible, and easy to operate. The development of this novel control system will expedite the development of commercial PIII instrumentation. (C) 1998 American Institute of Physics.

Plasma immersion ion implantation (PIII) has recently been shown to be a viable method to fabricate silicon-on-insulator (SOI) materials using either the SPIMOX (separation by plasma implantation of oxygen) or the ion cut/wafer bonding method, We have recently modified and characterized a new generation plasma immersion ion implanter for SOI fabrication, and this paper will discuss some of the instrumental and processing issues, including the plasma source, mean free path consideration, and de sheath characteristics.

The high voltage and electromagnetic field environment poses a big challenge to a control system for plasma immersion ion implantation (PIII). The automation process must be immune to electric field interference produced by the high voltage power supply, modulator, radio-frequency or microwave plasma generator, MEVVA plasma sources, and so oil. We have recently designed and installed a distributed control system, PIIIDCS, to automate the operation of our PIII facility. Programmable logic controllers are used as the held control stations because of their good anti-interference ability and good real time response. A DH-485 network is used as the communication link between the field controllers and the management station in order to improve the robustness and reliability of the system. The newly developed interface is designed to work in a graphic mode in Microsoft Windows 95. Test runs have shown that the system is reliable, flexible, and easy to operate. The development of this novel control system will expedite the development of commercial PIII instrumentation. (C) 1998 American Institute of Physics.

Plasma immersion ion implantation (PIII) has recently been shown to be a viable method to fabricate silicon-on-insulator (SOI) materials using either the SPIMOX (separation by plasma implantation of oxygen) or the ion cut/wafer bonding method, We have recently modified and characterized a new generation plasma immersion ion implanter for SOI fabrication, and this paper will discuss some of the instrumental and processing issues, including the plasma source, mean free path consideration, and de sheath characteristics.