Exposure of W-TiC/Cu Functionally Graded Materials in the Edge Plasma of HT-7 Tokamak

Six-layered W-TiC/Cu functionally graded materials were fabricated by resistance sintering under ultra-high pressure and exposed in the edge plasma of HT-7 tokamak. Microstruc- ture morphologies show that the TiC particles distribute homogeneously in the W matrix, strength- ening the grain boundary, while gradient layers provide a good compositional transition from W- TiC to Cu. After about 360 shots in the HT-7 tokamak, clear surface modification can be observed after plasma exposure, and the addition of nano TiC particles is beneficial to the improvement of plasma loads resistance of W.

A New Type of Multielements-Doped,Carbon-based Materials Characterized by High-thermoconductiv-ity,Low Chemical Sputtering,Low RES Yield and Exposure to Plasma

Low-Z materials, such as carbon-based materials and Be, are major plasma-facing material (PFM) for current, even in future fusion devices. In this paper, a new type of multielement-doped carbon-based materials developed are presented along with experimental re-sults of their properties. The results indicate a decrease in chemical sputtering yield by one order of magnitude, a decrease in both thermal shock resistance and radiation-enhanced sublimation, an evidently lower temperature desorption spectrum, and combined properties of exposing to plasma.

X-Ray Diffraction Study of Plasma Exposed and Annealed AlSb Bilayer Thin Film

Aluminum antimony seems to be a promising semiconducting material for high temperature applications, especially for transistors and P-N junction diodes. Additionally, it is a highly efficient solar material. This paper discusses the plasma induced bilayer diffusion of A1Sb bilayer thin films using X-ray diffractogram. A1Sb bilayer thin films were prepared on a glass substrate by vacuum evaporation technique. The effect of plasma exposure time and annealing temperature on the micro-structural parameters were investigated. X-ray diffraction studies show that the cubic crystals of A1 orient along the （111） plane and the hexagonal crystals of Sb orient along the （003） plane. Newly formed cubic crystals of A1Sb are oriented along the （200） plane and they are formed due to the simultaneous growth of A1 and Sb crystals during plasma exposure.

Effect of Oxygen Plasma on Low Dielectric Constant HSQ (Hydrogensilsesquioxane) Films

The commercially available hydrogensilsesquioxane （HSQ） offers a low dielectric constant. In this paper, the impact of oxygen plasma treatment has been investigated on the low- k HSQ films. Fourier transform infrared （FTIR） spectroscopy was used to identify the network structure and cage structure of Si-O-Si bonds and other possible bonds after treatments. C-V and I-V measurements were used to determine the dielectric constant, the electronic resistivity and the breakdown electric field, respectively. The result indicates that oxygen plasma treatment will damage the HSQ films by removing the hydrogen content. Both dielectric constant and leakage current density increase significantly after oxygen plasma exposure. The dielectric constant and leakage current density can both be decreased by annealing at 350 ℃ for 1.5 h in nitrogen ambient. The reason is that the open porous of the external films can be modified and density of thin film be increased. The rough surface can be smoothed.

Work Function Optimization Technology of Indium Tin Oxide Films

Indium tin oxide(In_(2)O_(3)∶Sn)film is one of the most potential materials in the field of semiconductor industry.However,untreated In2O3∶Sn film has a low work function which can result in a high energy barrier that hinders the passage of carriers through the interface,thus leading to poor overall performance of directly prepared devices.In this study,crystalline transparent conductive In_(2)O_(3)∶Sn films were prepared by plasma exposure assisted magnetron sputtering under room temperature.Based on multiple testing methods,it can be found that the low temperature crystallization characteristics of In_(2)O_(3)∶Sn film were enhanced and the work function was effectively improved after Ar^(+)plasma exposure.The increase of the work function of In_(2)O_(3)∶Sn film was due to the increment of Sn⁃O bond on the surface brought by the transition from low oxidation state Sn^(2+)to high oxidation state Sn^(4+)under the action of high exposure.