Our recent studies of oxidation processes on high-index silicon surfaces are reviewed. Interface trap densities, D_it, at the thermally oxidized Si surfaces were systematically investigated for (001), (111), (110), (120), (331) and (113) orientations. Structure model of the SiO₂/Si interface on (113) substrate was proposed based on the analysis of the optical measurements. The initial oxidation processes on high-index silicon surfaces with (113), (120) and (331) orientations at high temperatures have been investigated by X-ray photoelectron spectroscopy, and the results were compared with the case of (001) orientation. It has been shown that monolayer oxidation on high-index silicon surfaces can be characterized through chemical shift in the core level of the Si 2p and O 1s states, and in addition through evaluation of oxide thickness, oxide composition and band bending.

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  We report the applications of a hard X-ray photoelectron spectroscopy to the characterization of SiO₂/Si(001) systems. Large escape depth of high-energy photoelectron enables us to probe buried layers and their interfaces in multilayer structures. Estimation of SiO₂ overlayer thicknesses up to 25 nm by angle resolved XPS was possible in SiO₂/Si(001) samples. Determination of the thickness profile of a wedged shape SiO₂ buried layer was successfully done in Ir (8 nm)/HfO₂ (2.2 nm)/thickness graded-SiO₂ (0-10 nm)/Si(100). The Si 1s core level showed a SiO₂ thickness dependent shift, which was ascribed to fixed charge at the SiO₂-Si interface. Energy distribution of interface states at ultrathin thermal oxide/Si(100) interfaces were determined by Si 1s core level shift by applying gate bias in metal-oxide-semiconductor (MOS) structure with 5 nm Au gate electrodes.

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  Oxidation locally induced on a material surface by the use of scanning probe microscope (SPM)-based techniques is applicable to nanofabrication of a wide variety of materials including metals, semiconductors, inorganic compounds and organic materials. The mechanism of the SPM-induced local oxidation in the presence of the adsorbed water column formed at the SPM tip/sample junction is ascribed to electrochemical oxidation, that is, anodization, proceeding in the water nano-column, when the bias polarity is positive for the sample substrate. As well as scanning probe anodization of Si and Ti, a scanning probe lithography process in which an alkyl self-assembled monolayer (SAM) as a resist film patternable by anodization is described in this review. The patterned SAM was successfully applied to an etch mask in order to fabricate nano-grooves on Si. Besides oxidation, an example of nano-patterning based on electrochemical reduction is also demonstrated.

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  In this article, two common methods to evaluate the outgassing properties of vacuum system materials, thermal desorption spectroscopy (TDS) and the method of switching between two pumping paths (SPP), are discussed. TDS can evaluate the outgassing properties of small samples, while SPP method can measure low outgassing rate, such as the case after baking. Ion gauges and/or quadrupole mass spectrometers (QMS) consist of the TDS and SPP setups. In these cases, QMS are typically calibrated using a standard conductance element (SCE). The calibration using the SCE enables the direct conversion of the QMS ion current into the gas flow rate.

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  The emission currents of zinc oxide (ZnO) and carbon nanotube (CNT) cold cathodes show continuous degradation in sealed field emission (FE) devices when the anode voltages are maintained at a constant value; more stable currents are observed when the same cathodes are operated under ultra-high vacuum (UHV) conditions. This shows that ambient gases in the devices play an important role in degrading the emission currents of ZnO and CNT cathodes. To investigate the gas conditions in sealed FE devices, a vacuum system with a quadrupole mass spectrometer (QMS) was employed here. QMS data obtained before and after the gases in the FE devices were removed showed that the residual gases in the CNT-FE panels were H₂, CH₄, CO, and Ar, while in the ZnO-FE panels the residual gases were H₂, CH₄, CO, Ar, and CO₂. It was clear that the residual gases in the two kinds of FE devices were slightly different; this was mainly due to the different cathode materials used in the FE devices. The residual gases affected the emission current of the CNT and ZnO FE devices by changing the work function at the cathode surface; this was confirmed by the F-N curves measured when the same cathodes were tested in the devices and in the UHV chamber.

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  Low vacuum has numerous applications especially in the industrial processes where different gases are mixed under controlled environment. In such cases, the system must have the capability to provide controlled atmosphere which can enhance the quality of the end product. A low vacuum system has been developed by Vacuum Laboratory at Korea Research Institute of Standards and Science (KRISS) that can be used for the generation for stable pressure points in the pressure range from 1 Pa-133 Pa during continuous flow mode. The system's chamber is made of SS 304 and equipped with latest vacuum measuring/regulating instruments like CDGs, MFCs, RGA, RVC etc. This paper describes some established features of the system.

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