Microstructural characterization

R, D. Jacobson, S. R. Wilson, G. A. Al-Jumaily, J. R, McNeil, and J. M. Bennett. Microstructure Characterization by Angle-Resolved Scatter and Comparison to Measurements Made by Other Techniques. To be published in AppL Opt. This work discusses the band width and modulation transfer function of the scatterometer, stylus profilometer, optical pro-filometer, and total integrated scattering systems, and gives results of mea suring several surhices using all techniques. 

Schwartz, R. W. Assink, R. A. Headley, T. J. 1992. Solution chemistry effects in PZT thin film processing spectroscopic and microstructural characterization. In Ferroelectric Thin Films II, edited by Kingon, A. I. Myers, E. R. Tuttle, B. Mat. Res. Soc. Symp. Proc. 243 245-254. 

Wada, T. Nishitani, M. Negami, T. Kohara, N. Ikeda, M. Terauchi, M. 1994. Microstructural characterization of substrate-type and superstrate-type CuInSe2 thin film solar cells. Proc. 12th European Photovoltaic Solar Energy Conf. pp. 1542-1545. 

Song HS, Hyun SH, Moon J, and Song RH. Electrochemical and microstructural characterization of polymeric resin-derived multilayered composite cathode for SOFC. J. Power Sources 2005 145 272-277. 

The development and manufacture of organic light-emitting diodes (OLEDs) have demanded the use of the most advanced microstructural characterization techniques and sophisticated performance measurement devices [1-14], In this chapter, we will briefly describe these techniques and devices and review how scientists and engineers utilize them to improve the performance of OLEDs. 

In the last century, many microstructural characterization techniques have been developed, such as electron microscopy, atomic tunneling microscopy, photoelectron spectroscopy, Raman spectroscopy, etc. The structure of the OLED-based displays is such that many pixels are arranged orderly in the x-y plane. The size and number of pixels determine the resolution and size of the display. Along the z-axis, several layers are stacked on each other. These layers... 

Transmission electron microscopy (TEM) is a powerful and mature microstructural characterization technique. The principles and applications of TEM have been described in many books [16 20]. The image formation in TEM is similar to that in optical microscopy, but the resolution of TEM is far superior to that of an optical microscope due to the enormous differences in the wavelengths of the sources used in these two microscopes. Today, most TEMs can be routinely operated at a resolution better than 0.2 nm, which provides the desired microstructural information about ultrathin layers and their interfaces in OLEDs. Electron beams can be focused to nanometer size, so nanochemical analysis of materials can be performed [21]. These unique abilities to provide structural and chemical information down to atomic-nanometer dimensions make it an indispensable technique in OLED development. However, TEM specimens need to be very thin to make them transparent to electrons. This is one of the most formidable obstacles in using TEM in this field. Current versions of OLEDs are composed of hard glass substrates, soft organic materials, and metal layers. Conventional TEM sample preparation techniques are no longer suitable for these samples [22-24], Recently, these difficulties have been overcome by using the advanced dual beam (DB) microscopy technique, which will be discussed later. 

In conclusion, we have presented many microstructural characterization and performance measurement techniques, together with examples of how to use these techniques to improve the performance of OLEDs. Seeing the enormous progress recently, we expect more and more OLED-related products will be used in our daily life. 

V-Ti-Ni alloys and Fe- /Co-Based metallic glasses have been evaluated with respect to hydrogen permeability for potential use in hydrogen purification membrane reactor application. Microstructural characterization of the V-Ti-Ni alloy using SEM has shown similar microstructural features to a previously evaluated Nb-Ti-Ni alloy namely, the occurrence of a primary phase surrounded by interdendritic eutectic. 

M. -Trung Tran, N. S. Gnep, G. Szabo, and M. Guisnet, Influence of the calcination temperature on the acidic and catalytic properties of sulphated zirconia, Appl. Catal. A 171, 207-217 (1998). P. Canton, R. Olindo, F. Pinna, G. Strukul, P. Rieflo, M. Meneghetti, G. Cerrato, C. Morterra, and A. Benedetti, Alumina-promoted sulfated zirconia system Structure and microstructure characterization, Chem. Mater. 13, 1634-1641 (2001). 

Electron diffraction has a main advantage with respect to the other diffraction techniques it can be performed at a microscopic and nanoscopic scales in correlation with the image of the diffracted area. The various types of electron diffraction pattern have many applications both in the fields of structure and microstructure characterizations. 

Recent progress in electron diffraction has significantly broadened its applications from a primary a microstructure characterization tool to an accurate structure analysis technique that traditionally belongs almost exclusively to the domain of X-ray and neutron diffraction. This development is timely since the focus of modem materials feature size is increasingly on nanoscale stmctures, where the electron high spatial... 

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