功率和埚转对直拉单晶硅漏硅事故率的影响及分析

在CZ法硅单晶生长中,化料过程是原生硅固液形态转换的主要过程,由于化料阶段功率最高,也是最容易发生事故的过程,其中溅硅、漏硅等事故对石墨热场、产品品质、安全等方面有着较大的不良影响。

Monte Carlo simulation for the sputtering yield of Si_3N_4 thin film milled by focused ion beams

The sputtering yield of the Si3N4 thin film is calculated by Monte Carlo method with different parameters. The dependences of the sputtering yield on the incident ion energy, the incident angle and the number of Gallium （Ga） and Arsenic （As） ions are predicted. The abnormal sputtering yield for As at 90 keV occurs when the incident angle reaches the range between 82° and 84°.

Effects of ratio of hydrogen flow on microstructure of hydrogenated microcrystalline silicon films deposited by magnetron sputtering at 100 ℃

Hydrogenated microcrystalline silicon(μc-Si:H)films were prepared on glass and silicon substrates by radio frequency magnetron sputtering at 100°C using a mixture of argon(Ar)and hydrogen(H2)gasses as precursor gas.The effects of the ratio of hydrogen flow(H2/(Ar+H2)%)on the microstructure were evaluated.Results show that the microstructure,bonding structure,and surface morphology of theμc-Si:H films can be tailored based on the ratio of hydrogen flow.An amorphous to crystalline phase transition occurred when the ratio of hydrogen flow increased up to 50%.The crystallinity increased and tended to stabilize with the increase in ratio of hydrogen flow from 40%to 70%.The surface roughness of thin films increased,and total hydrogen content decreased as the ratio of hydrogen flow increased.Allμc-Si:H films have a preferred(111)orientation,independent of the ratio of hydrogen flow.And theμc-Si:H films had a dense structure,which shows their excellent resistance to post-oxidation.

Fabrication of Multilayer Optical interference Filter as Colored Glazed Buildings Fa（;ades for Thermal Solar Collectors Using MgF2/SiO2

A simple idea to obtain a desired color that hiding the black color, and the visibility of tubes and corrugations of the metal sheet （absorber） of the thermal solar collectors which is consider the main obstacle to facade integration buildings of solar thermal collectors will be presented in this study by designing a multilayer optical interference filter during RF magnetron sputtering process. This filter work as antireflection coating in the near IR region and also includes a high colored reflectance at a specific wavelength in the visible region, this is to gain an esthetic aspect for the thermal solar collector which can be used as building facades by employing appropriate dielectric materials with high refractive index （H） like SiO2 and low refractive index （L） such as MgF2 which they deposited on glass substrate for quarterwave thickness and for the optical model air//HL//glass.

Hybrid Silicon-Carbon Nanostructured Composites as Superior Anodes for Lithium Ion Batteries

We have successfully fabricated a hybrid silicon-carbon nanostructured composite with large area （about 25.5 in^2） in a simple fashion using a conventional sputtering system. When used as the anode in lithium ion batteries, the uniformly deposited amorphous silicon （a-Si） works as the active material to store electrical energy, and the pre-coated carbon nanofibers （CNFs） serve as both the electron conducting pathway and a strain/stress relaxation layer for the sputtered a-Si layers during the intercalation process of lithium ions. As a result, the as-fabricated lithium ion batteries, with deposited a-Si thicknesses of 200 nm or 300 nm, not only exhibit a high specific capacity of 〉2000 mA.h/g, but also show a good capacity retention of over 80% and Coulombic efficiency of 〉98% after a large number of charge/discharge experiments. Our approach offers an efficient and scalable method to obtain silicon-carbon nanostructured composites for application in lithium ion batteries.

Effects of ion bombardment on microcrystalline silicon growth by inductively coupled plasma assistant magnetron sputtering

Hydrogenated microcrystalline silicon （mc-Si：H） thin films were deposited by inductively coupled plasma assistant magnetron sputtering （ICP-MS） in an Ar-H2 gas mixture. The role of ion bombardment in the growth of mc-Si：H films was studied with increasing negative bias voltages on the substrate holder from 0 to -100 V. Raman scattering, X-ray diffraction （XRD）, Fourier transform infrared （FTIR） spectroscopy and transmission electron microscopy （TEM） were performed to investigate the microstructure changes of deposited Si films. Raman scattering showed that the high energy ion bombardment resulted in crystalline degradation of Si films. The XRD results showed the decrease and even elimination of preferential growth orientation of crystalline Si films with ion bombardment energy increase. The SiH bonding configuration changes and the increase of bonded hydrogen concentration were determined with the analysis of FTIR spectra. Furthermore, the dramatic evolution of cross-sectional morphology of Si thin films was detected by TEM observation.