A new method in time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging, the droplet-enhanced method, was developed for the molecular analysis of biomaterials. To facilitate the ionization of biomolecules, a small amount of aqueous solution containing sodium salt or an acid as ionization-enhancing agents was dropped onto peptide samples before TOF-SIMS measurement. Using this method, we have successfully obtained strong molecular secondary ion signals from molecular weight (MW) < 7649 peptide samples while maintaining their natural distribution. This method enables to visualize dot-patterned 20 amol insulin (MW 5733) with our bubble jet (BJ) printing technology. We also demonstrated the visualization of dot-patterned digested protein distribution with the BJ printing technology.

  “Non-linear Effect” is one of the unique phenomena in cluster ion impacts, where many atoms are collided each other instantaneously. Novel techniques for Nano-Processing and material analysis have been developed in the last decade, and will give us an opportunity to overcome issues in conventional technique with monomer ions. Recent progress in cluster ion beam is reported from the viewpoint of Nano-Processing and advanced material analysis.

  Cluster ions have been increasingly applied to surface analysis of organic and bio materials. Recent progress of cluster ion beam formation, sputtering process of cluster ions, and their application for surface analysis are reviewed.

  Time of flight type secondary ion mass spectrometry (TOF-SIMS) equipped with the cluster ion source such as SF⁵⁺, Au³⁺, C₆₀⁺ as primary ion has been put to practical use in the last decade. Cluster ion beam has advantage of high sputtering yield and high secondary ionization yield without introducing severe damage on material surfaces. Substantial enhancement of secondary ion yield for bio-molecules is strongly demanded, and consequently, use of giant cluster ions for SIMS is attracted very recently. In this paper, the development of SIMS with the giant cluster ions (water droplet cluster) is reported.

  Three kinds of peak detecting algorithms for AES and XPS spectrum are proposed. These peak detecting methods are composed of three stages of algorithms: rough estimation of the background; direct calculation of the peak and background relation at the candidate peak; and application of the second derivative curve. This report provides concrete methods of finding peaks in a measured spectrum of surface analysis based on an empirical investigation of how to detect significant signals among faint ones. Algorithms and characteristics of the respective peak detecting methods are discussed.

  The spatial resolution of an electron optical instrument has its theoretical limit originating from the wave nature of electrons. This effect is called the diffraction aberration, which complements geometrical optics valid in the limit of very short wavelengths. In this chapter we shall give a diffraction treatment of spatial resolution in the presence of spherical and chromatic aberrations, and examine an optical system as a filter of spatial frequencies on the basis of Abbe's imaging theory.