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The development of sputtered coatings with improved hardness-toughness property combination is widely sought after. Multi-element ceramic carbide (Hf-Nb-Ta-Zr)C coatings with excess carbon, synthesized by DC co-sputtering is presented in this study as a promising candidate to achieve this objective. The specific roles of microstructure and residual stress are decoupled in order to understand their influence on the mechanical properties. Extensive mechanical characterization through in situ testing of focused ion beam fabricated microcantilevers and nanoindentation based approaches are adopted to quantitatively separate the effect of residual stresses on the fracture toughness of the (Hf-Nb-Ta-Zr)C coatings. Residual stress free, microcantilever testing in notched and unnotched conditions, in combination with microstructural characterization unambiguously reveals the intrinsic mechanical behavior of coatings, which solely depend on the microstructure. On the other hand, nanoindentation based testing techniques probe the influence of residual stress and microstructure on the measured mechanical properties. The segregation and thickening of carbon-rich clusters, especially to the grain boundaries with increasing deposition temperatures is speculated to lead to substantial degradation in all mechanical properties measured. An easier fracture path through grain boundaries leads to a reduction in fracture resistance, which is possibly related to carbon enrichment.

The development of sputtered coatings with improved hardness-toughness property combination is widely sought after. Multi-element ceramic carbide (Hf-Nb-Ta-Zr)C coatings with excess carbon, synthesized by DC co-sputtering is presented in this study as a promising candidate to achieve this objective. The specific roles of microstructure and residual stress are decoupled in order to understand their influence on the mechanical properties. Extensive mechanical characterization through in situ testing of focused ion beam fabricated microcantilevers and nanoindentation based approaches are adopted to quantitatively separate the effect of residual stresses on the fracture toughness of the (Hf-Nb-Ta-Zr)C coatings. Residual stress free, microcantilever testing in notched and unnotched conditions, in combination with microstructural characterization unambiguously reveals the intrinsic mechanical behavior of coatings, which solely depend on the microstructure. On the other hand, nanoindentation based testing techniques probe the influence of residual stress and microstructure on the measured mechanical properties. The segregation and thickening of carbon-rich clusters, especially to the grain boundaries with increasing deposition temperatures is speculated to lead to substantial degradation in all mechanical properties measured. An easier fracture path through grain boundaries leads to a reduction in fracture resistance, which is possibly related to carbon enrichment.

The development of sputtered coatings with improved hardness-toughness property combination is widely sought after. Multi-element ceramic carbide (Hf-Nb-Ta-Zr)C coatings with excess carbon, synthesized by DC co-sputtering is presented in this study as a promising candidate to achieve this objective. The specific roles of microstructure and residual stress are decoupled in order to understand their influence on the mechanical properties. Extensive mechanical characterization through in situ testing of focused ion beam fabricated microcantilevers and nanoindentation based approaches are adopted to quantitatively separate the effect of residual stresses on the fracture toughness of the (Hf-Nb-Ta-Zr)C coatings. Residual stress free, microcantilever testing in notched and unnotched conditions, in combination with microstructural characterization unambiguously reveals the intrinsic mechanical behavior of coatings, which solely depend on the microstructure. On the other hand, nanoindentation based testing techniques probe the influence of residual stress and microstructure on the measured mechanical properties. The segregation and thickening of carbon-rich clusters, especially to the grain boundaries with increasing deposition temperatures is speculated to lead to substantial degradation in all mechanical properties measured. An easier fracture path through grain boundaries leads to a reduction in fracture resistance, which is possibly related to carbon enrichment.

The development of sputtered coatings with improved hardness-toughness property combination is widely sought after. Multi-element ceramic carbide (Hf-Nb-Ta-Zr)C coatings with excess carbon, synthesized by DC co-sputtering is presented in this study as a promising candidate to achieve this objective. The specific roles of microstructure and residual stress are decoupled in order to understand their influence on the mechanical properties. Extensive mechanical characterization through in situ testing of focused ion beam fabricated microcantilevers and nanoindentation based approaches are adopted to quantitatively separate the effect of residual stresses on the fracture toughness of the (Hf-Nb-Ta-Zr)C coatings. Residual stress free, microcantilever testing in notched and unnotched conditions, in combination with microstructural characterization unambiguously reveals the intrinsic mechanical behavior of coatings, which solely depend on the microstructure. On the other hand, nanoindentation based testing techniques probe the influence of residual stress and microstructure on the measured mechanical properties. The segregation and thickening of carbon-rich clusters, especially to the grain boundaries with increasing deposition temperatures is speculated to lead to substantial degradation in all mechanical properties measured. An easier fracture path through grain boundaries leads to a reduction in fracture resistance, which is possibly related to carbon enrichment.

The development of sputtered coatings with improved hardness-toughness property combination is widely sought after. Multi-element ceramic carbide (Hf-Nb-Ta-Zr)C coatings with excess carbon, synthesized by DC co-sputtering is presented in this study as a promising candidate to achieve this objective. The specific roles of microstructure and residual stress are decoupled in order to understand their influence on the mechanical properties. Extensive mechanical characterization through in situ testing of focused ion beam fabricated microcantilevers and nanoindentation based approaches are adopted to quantitatively separate the effect of residual stresses on the fracture toughness of the (Hf-Nb-Ta-Zr)C coatings. Residual stress free, microcantilever testing in notched and unnotched conditions, in combination with microstructural characterization unambiguously reveals the intrinsic mechanical behavior of coatings, which solely depend on the microstructure. On the other hand, nanoindentation based testing techniques probe the influence of residual stress and microstructure on the measured mechanical properties. The segregation and thickening of carbon-rich clusters, especially to the grain boundaries with increasing deposition temperatures is speculated to lead to substantial degradation in all mechanical properties measured. An easier fracture path through grain boundaries leads to a reduction in fracture resistance, which is possibly related to carbon enrichment.

GaN thin films were utilized as an active channel layer to produce bottom-gate n-type thin-film transistors (TFTs). The GaN thin films with wurtzite structure were deposited by the reactive dc magnetron sputtering technique using liquid gallium target. The resulting GaN TFTs exhibit good electrical performance, including a field-effect mobility of 5 cm(2)/V . s, a threshold voltage of 11.5 V, an on/off current ratio of 6 x 10(6), and a subthreshold swing of 0.4 V/dec. The reported GaN TFTs have great potential in the application of next-generation flat-panel display.

GaN thin films were utilized as an active channel layer to produce bottom-gate n-type thin-film transistors (TFTs). The GaN thin films with wurtzite structure were deposited by the reactive dc magnetron sputtering technique using liquid gallium target. The resulting GaN TFTs exhibit good electrical performance, including a field-effect mobility of 5 cm(2)/V . s, a threshold voltage of 11.5 V, an on/off current ratio of 6 x 10(6), and a subthreshold swing of 0.4 V/dec. The reported GaN TFTs have great potential in the application of next-generation flat-panel display.

GaN thin films were utilized as an active channel layer to produce bottom-gate n-type thin-film transistors (TFTs). The GaN thin films with wurtzite structure were deposited by the reactive dc magnetron sputtering technique using liquid gallium target. The resulting GaN TFTs exhibit good electrical performance, including a field-effect mobility of 5 cm(2)/V . s, a threshold voltage of 11.5 V, an on/off current ratio of 6 x 10(6), and a subthreshold swing of 0.4 V/dec. The reported GaN TFTs have great potential in the application of next-generation flat-panel display.

Top-gate n-type GaN thin-film transistors (TFTs) based on AlN/GaN heterostructures were fabricated. GaN and AlN thin films were sequentially deposited by the reactive dc magnetron sputtering technique at room temperature on quartz. The proposed GaN TFTs exhibit good electrical performance, such as field mobility of 2.5 cm(2)/V . s, threshold voltage of 2.4 V, ON/OFF-current ratio of 1.2 x 10(5), and subthreshold swing of 0.5 V/dec. The proposed GaN TFT has great potential in the application of next-generation flat-panel displays.

Top-gate n-type GaN thin-film transistors (TFTs) based on AlN/GaN heterostructures were fabricated. GaN and AlN thin films were sequentially deposited by the reactive dc magnetron sputtering technique at room temperature on quartz. The proposed GaN TFTs exhibit good electrical performance, such as field mobility of 2.5 cm(2)/V . s, threshold voltage of 2.4 V, ON/OFF-current ratio of 1.2 x 10(5), and subthreshold swing of 0.5 V/dec. The proposed GaN TFT has great potential in the application of next-generation flat-panel displays.

n recent times Platinum (Pt), Iridium (Ir), Iridium oxide (IrO) and Platinum-Iridium (Pt-Ir) are the favorable microelectrode materials. They show excellent electrical and mechanical properties suitable for neural stimulation and sensing/recording purposes. But their long term stability and performance is still in question especially working in conductive saline environment. Titanium Nitride (TiN) is advantageous than the mentioned noble metals used as microelectrode material for nerve stimulation and sensing. TiN films are generally used in biomedical implants due to their good mechanical and high corrosion resistance with extreme biocompatibility. Here we talk over the capabilities of sputtered TiN material as a microelectrode material with respect to its mechanical and electrical properties. Also, we discuss the initial results for sputtered TiN layers and its surface properties suitable for electrical stimulation and sensing neuronal activity. TiN was chosen because it readily lends itself to reactive sputtering method and provides significant charge injection rates 23 mC/cm2 with excellent corrosion and biocompatibility properties. Titanium (Ti) and TiN thin films of 200 nm thick were deposited by DC magnetron sputtering process on plain silicon substrates. Initial AFM and XRD characterization study was carried to study the crystal structural properties of these thin films., Microelectronics, Electrical Engineering, Mathematics and Computer Science

Top-gate n-type GaN thin-film transistors (TFTs) based on AlN/GaN heterostructures were fabricated. GaN and AlN thin films were sequentially deposited by the reactive dc magnetron sputtering technique at room temperature on quartz. The proposed GaN TFTs exhibit good electrical performance, such as field mobility of 2.5 cm(2)/V . s, threshold voltage of 2.4 V, ON/OFF-current ratio of 1.2 x 10(5), and subthreshold swing of 0.5 V/dec. The proposed GaN TFT has great potential in the application of next-generation flat-panel displays.

n recent times Platinum (Pt), Iridium (Ir), Iridium oxide (IrO) and Platinum-Iridium (Pt-Ir) are the favorable microelectrode materials. They show excellent electrical and mechanical properties suitable for neural stimulation and sensing/recording purposes. But their long term stability and performance is still in question especially working in conductive saline environment. Titanium Nitride (TiN) is advantageous than the mentioned noble metals used as microelectrode material for nerve stimulation and sensing. TiN films are generally used in biomedical implants due to their good mechanical and high corrosion resistance with extreme biocompatibility. Here we talk over the capabilities of sputtered TiN material as a microelectrode material with respect to its mechanical and electrical properties. Also, we discuss the initial results for sputtered TiN layers and its surface properties suitable for electrical stimulation and sensing neuronal activity. TiN was chosen because it readily lends itself to reactive sputtering method and provides significant charge injection rates 23 mC/cm2 with excellent corrosion and biocompatibility properties. Titanium (Ti) and TiN thin films of 200 nm thick were deposited by DC magnetron sputtering process on plain silicon substrates. Initial AFM and XRD characterization study was carried to study the crystal structural properties of these thin films., Microelectronics, Electrical Engineering, Mathematics and Computer Science

We motivate our studying on simulating thin film deposition processes that can be done by sputtering processes. In the last years, the research in producing high temperature films by depositing of low pressure processes have increased. Due to standard applications in deposing TiN and TiC, that are immense, recently also deposition with new material classes known as MAX-phases became be more and more important. The MAX-phase are nanolayered terniar metal-carbides or -nitrids, where M is a transition metal, A is an A-group element (e.g. Al, Ga, In, Si, etc.) and X is C (carbon) or N (nitrid). We present a particle tracking model for low temperature and low pressure plasma. Several collision models are presented for projectile and target collisions in order to compute the mean free path and the differential cross section (angular distribution of scattered projectiles) of the scattering process. The detailed description of collision models is of highest importance in Monte Carlo Simulations of high power pulsed magnetron sputtering and DC sputtering. We derive an equation for the mean free path for arbitrary interactions (cross sections) that include the relative velocity between the particles. We apply our results to two major interaction models: hard sphere interaction and Screened Coulomb interaction. Both types of interaction separates DC sputtering from HPPMS. Further investigations presented in this paper involve modifications of the scattering angle probability distribution due to initially moving background targets. In order to tackle this modification, an appropriate Monte-Carlo-Markov-Chain approach is proposed.

We motivate our study by simulating the particle transport of a thin film deposition process done by PVD (physical vapor deposition) processes. In this paper we present a new model taken into account a higher pressure regimes in a sputter process. We propose a collision models for projectile and target collisions in order to compute the mean free path and include the virial coefficients that considered interacting gas particles. A detailed description of collision models of the Monte Carlo Simulations is discussed for high power impulse magnetron sputtering (HIPIMS) and DC sputtering in lower pressure regimes. We derive an equation for the mean free path for arbitrary interactions (cross sections) which (most important) includes the relative velocity between the projectiles and targets based on physical first principles and extend with higher order Virial terms . At the substrate we simulate the implantation of the particles with the help of TRIM, based on result of the energy that are computed with the Monte Carlo methods. We apply our results to three interaction models: hard sphere interaction, Screened Coulomb interaction and a mixture of the last mentioned interactions. The deposition to realistic geometries, which have sharp angles included, are presented. Because of the strong convective process of a HIPIMS method, the low diffusion process allows not to deposit into delicate geometries, see [Christ2005]. This can be improved by rotating the target to a more or less perpendicular angle.

We motivate our studying on simulating thin film deposition processes that can be done by sputtering processes. In the last years, the research in producing high temperature films by depositing of low pressure processes have increased. Due to standard applications in deposing TiN and TiC, that are immense, recently also deposition with new material classes known as MAX-phases became be more and more important. The MAX-phase are nanolayered terniar metal-carbides or -nitrids, where M is a transition metal, A is an A-group element (e.g. Al, Ga, In, Si, etc.) and X is C (carbon) or N (nitrid). We present a particle tracking model for low temperature and low pressure plasma. Several collision models are presented for projectile and target collisions in order to compute the mean free path and the differential cross section (angular distribution of scattered projectiles) of the scattering process. The detailed description of collision models is of highest importance in Monte Carlo Simulations of high power pulsed magnetron sputtering and DC sputtering. We derive an equation for the mean free path for arbitrary interactions (cross sections) that include the relative velocity between the particles. We apply our results to two major interaction models: hard sphere interaction and Screened Coulomb interaction. Both types of interaction separates DC sputtering from HPPMS. Further investigations presented in this paper involve modifications of the scattering angle probability distribution due to initially moving background targets. In order to tackle this modification, an appropriate Monte-Carlo-Markov-Chain approach is proposed.

We motivate our study by simulating the particle transport of a thin film deposition process done by PVD (physical vapor deposition) processes. In this paper we present a new model taken into account a higher pressure regimes in a sputter process. We propose a collision models for projectile and target collisions in order to compute the mean free path and include the virial coefficients that considered interacting gas particles. A detailed description of collision models of the Monte Carlo Simulations is discussed for high power impulse magnetron sputtering (HIPIMS) and DC sputtering in lower pressure regimes. We derive an equation for the mean free path for arbitrary interactions (cross sections) which (most important) includes the relative velocity between the projectiles and targets based on physical first principles and extend with higher order Virial terms . At the substrate we simulate the implantation of the particles with the help of TRIM, based on result of the energy that are computed with the Monte Carlo methods. We apply our results to three interaction models: hard sphere interaction, Screened Coulomb interaction and a mixture of the last mentioned interactions. The deposition to realistic geometries, which have sharp angles included, are presented. Because of the strong convective process of a HIPIMS method, the low diffusion process allows not to deposit into delicate geometries, see [Christ2005]. This can be improved by rotating the target to a more or less perpendicular angle.

The electronic structure of U-diluted in an Ag matrix has been studied in situ by ultraviolet and X-ray photoelectron spectroscopy (UPS and XPS, respectively). UxAg100-x thin films (x = 0-100 at.%) were produced by sputter co-deposition in an Ar atmosphere. UPS spectra of the Ag-4d line indicate formation of a homogeneous mixture despite the fact that U and Ag do not form stable alloys. A major goal of this work was to find out whether the dilution of U atoms in an inert matrix with no bonding states induces the localisation of the U-5f states. Both U-4f core level spectra and the U-5f spectra indicate U-5f delocalisation, down to 5 at.% of uranium in UxAg100-x films., QC 20150728