In organic light-emitting devices (OLEDs), optoelectronic functions are separated into multiple organic stacked layers sandwiched by a pair of electrodes, and the stacked layer structure has great impacts on the device characteristics．However, each organic layer has a very thin thickness from only several nm to several tens of nm, and the precise evaluation of the thickness is difficult． In this context, we focused on non-destructive neutron reflectivity (NR) measurements for the precise evaluation of layer structures． In this article, we report solution-processed stacked organic/organic layer structures investigated by NR, and their influences on OLED performances.

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The usage of COMPRO12 (part 1 and part 2) introduced the usage of data processing in COMPRO. In this lecture, the usage of COMPRO12 will be continuously explained with the basic introduction of algorithms used in COMPRO.

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The reaction of O₂ and residual H over platinum in high vacuum, at temperatures from 60 K to room temperature, was studied by using field-evaporation techniques, including field ion microscopy (FIM) and atom probe (AP), which enabled in-situ analysis of surface structure and chemical composition analysis at atomic scale. This study aimed to obtain detailed information about the reaction of O₂ and residual H on a Pt surface. Hydrogen is a near-ubiquitous element and field-evaporation technique can be used to study the residual H in high vacuum conditions. Three H species on a Pt surface were observed H⁺, H₂⁺, and H₃⁺ in high vacuum (10^–8 Pa). Upon the exposure of the nanoscale Pt surface to O₂ atmosphere (10^-5 Pa), H₂O was produced for the temperatures above 135 K. According to the peak intensity ratio between H_2-3O⁺ and O₂ during the warming up process, H₂ surface diffusion along the shank and the bulk H diffusion were faster at higher temperatures. In addition, we found that the planes surrounding the {111} plane, such as the {240} plane, were more active owning to their particularly rough atomic corrugation.

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Energy dispersive micro X-ray fluorescence analyzer (EDμXRF） can be measured in the atmosphere with simple sample preparation and easy operation, so it is used in a wide range of fields such as component analysis of materials, failure analysis, foreign matter analysis, precious metal grade judgment and forensic analysis. In this paper describes the technology used for the main components of EDμXRF and the concept of observation optical system, and introduces an application analysis example using this instruments.

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XPS is one of the surface analysis technique like AES (Auger Electron Spectroscopy) and TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry). It is possible to analyze the qualitative, quantitative chemical state of material surface. XPS is the most widely used technique among the surface analysis instrument because is easy operation, fruitful database and easy charge correction method. In this paper the principal of XPS, the configuration of the equipment, the basics of measurement and data analysis and application is described.

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[in Japanese]

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