Thin films. Auger electron spectroscopy

Auger electron spectroscopy is the most frequently used surface, thin-film, or interface compositional analysis technique. This is because of its very versatile combination of attributes. It has surface specificity—a sampling depth that varies... 

We have undertaken a series of experiments Involving thin film models of such powdered transition metal catalysts (13,14). In this paper we present a brief review of the results we have obtained to date Involving platinum and rhodium deposited on thin films of tltanla, the latter prepared by oxidation of a tltanliua single crystal. These systems are prepared and characterized under well-controlled conditions. We have used thermal desorption spectroscopy (TDS), Auger electron spectroscopy (AES) and static secondary Ion mass spectrometry (SSIMS). Our results Illustrate the power of SSIMS In understanding the processes that take place during thermal treatment of these thin films. Thermal desorption spectroscopy Is used to characterize the adsorption and desorption of small molecules, In particular, carbon monoxide. AES confirms the SSIMS results and was used to verify the surface cleanliness of the films as they were prepared. 

Electrochemical behavior of ultrathin Pd epitaxial layers deposited electrochem-ically on Au(lll) and Au(lOO) has been found to be strongly dependent on the surface structures and the thickness of the Pd thin films [435]. From the kinetic studies of Pd deposition on Au(lll) electrode from K2 PdCU in 0.1 M H2 S O4, it has been deduced [436] that this process proceeds via an instantaneous nucleation and two-dimensional (2D) growth. Initial stages of Pd deposition on Au(llO) have also been studied by Robach et al. [437], who have applied STM, low-energy electron diffraction, and Auger electron spectroscopy for this purpose. 

Auger Another popular technique for thin film analysis is called Auger electron spectroscopy (AES). In this technique, an energetic electron beam (up to 10 keV) is used to probe a surface. The energetic electron can... 

Sample preparation. Thin films of PBTMSS for Rutherford backscattering spectroscopy (RBS) and general plasma etching studies were spun on polished silicon wafers from a 3.5% solution in chlorobenzene using a photoresist spinner. The films were baked for 10 to 20 min. at 105-120 X in air. PBTMSS films for Auger electron spectroscopy (AES) studies were spin-coated on silicon wafers previously coated with 2000 A of gold. Films for IR studies were spin-coated onto NaCl plates. 

In order to obtain a fundamental understanding of oxide surfaces, well-ordered thin oxide films, grown in ultrahigh vacuum (UHV) under well-controlled (clean) conditions, has turned out to be a successful approach ([8, 17, 38] and references therein). In contrast to many (insulating) bulk oxides, thin oxide films exhibit electrical and thermal conductivity sufficient for the application of surface sensitive imaging (e.g., STM) and spectroscopic methods (e.g., XPS Auger electron spectroscopy, AES and temperature-programmed desorption, TPD). 

AES Auger Electron Spectroscopy Thin films, surfaces Electrons 3-10 keV Auger electrons 20- 2000 eV 0.3-3 nm =30 nm Eiemenlai composition ol surface (except H, He) detection limit 0.1-1% 28,29... 

C. Argile and G.E. Rhead. Adsorbed Layer and Thin Film Growth Modes Monitored by Auger Electron Spectroscopy. Surf. Sci. Rep. 10 277 (1989). 

The analysis of metals by X-ray fluorescence has been widely used on geological and sediment samples, either deposited on filters or as thin films. The method can be made quantitative by using geological standards and transition metals can be determined in the 1-5 tg per g range. The surfaces of sediment particles can be examined by the direct use of electron microprobe X-ray emission spectrometry and Auger electron spectroscopy. Although these methods are not particularly sensitive, they can allow the determination of a depth-profile of trace metals within a sediment particle. 

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