SURFACE CHARACTERIZATION TECHNIQUES BASED ON ION BOMBARDMENT

The most common mode of chemical analysis presented herein has been the monitoring of elastically/inelastically scattered or recoiled incident beam species, or 

1 ppb — 0.1 ppm) and ability to detect/quantify any element in the Periodic Table. In contrast to common bulk MS methods such as matrix-assisted laser desorp-tion/ionization (MALDI) and electrospray ionization (ESI), SIMS analyzes samples in their native state without the need for a suitable matrix solution. As a result, SIMS is the best choice to characterize organic-based thin films and polymer surfaces. 

The operating principle of SIMS is not unlike other techniques in this section that is, a high-energy (1-30 keV) ion source is directed onto a sample surface. However, the absorption of this energy by the top ca. 50 A of the sample results in the sputtering 

Depending on the desired species to be analyzed, a variety of primary ion beams may be used such as Cs , Oj, O, Ar , and Ga . Whereas a cationic primary beam such as Cs+ is used to ionize electronegative elements e.g., O, C, N, chalcogens. 

There are two varieties of SIMS - static and dynamic. Static SIMS (often referred to as time-of-flight SIMS, TOF-SIMS) is often the method-of-choice, used for 

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