Argon sputtering

A new measurement technique, in-situ atomic force microscopy combined with XPS and scanning Auger electron microscopy and continuous argon sputtering, recently revealed that the films are not uni-... 

An argon-sputtered glassy carbon electrode was used. 

Fig. 27. Valence band spectra of oxidized Pu metal and sintered PUO2 for Hell excitation (40.8 eV), curve I Pu metal -I- PU2O3 curve 2 PU2O3 curve 3 PU2O3 -I- PUO2 curve 4 PUO2 (all for oxidized Pu metal) curve 5 sintered PuOj (Argon sputtered)...

Because electron-spectroscopic and ion-scattering methods yield information about the first seven atom layers, applying these techniques to metal-hydrogen kinetic problems requires incorporating depth-profiling capability. That is, an argon-sputtering gun must be incorporated into the analysis system to remove undesired surface material up to several nanometers deep. 

Fig. 21. Conduction and 4/ electron X-ray photoemission spectra of Sm and Co metals and of SmCos. Argon sputtering, used to clean samples, resulted in the faint lines seen in the vicinity of 12 eV. Vertical hatching in the 4—10 eV region of the SmCoj spectrum indicates the uncertainties. Ref. (48)...

In Fig. 20 the ESCA spectrum of the surface and of the bulk after two minutes argon sputtering is shown. 

Figure 2.17. Electron spectroscopy for chemical analysis ESCA) spectra of organometallic polymer films before and after exposure to oxygen plasma. The silicon 2p transition page 99) is shifted from 99.7 to 102.4 eV. The magnitude of the shift is consistent uMh conversion to SiO, where x is between 1.5 and 2. The Sn 3d transitions of the organotin compound above) undergo a similar shift 1.7 eV), consistent with generation of a SnOx surface, where x is again between 1.5 and 2. Argon sputter etching followed by ESCA analysis indicates that these oxide films are less than 100 A thick.

In a similar experiment, Belton et al. (30) deposited an Rh overlayer on a thin film of Ti02 (supported on metallic Ti) and annealed it at 773 K. By TPD they observed a significant loss in H2 chemisorption. Subsequent argon sputtering caused a decrease in the Ti/Rh ratio as detected by AES accompanied by an increase in the H2 uptake. This behavior was taken as evidence of the presence of a titania species on the Rh surface. In agreement with Sadeghi and Henrich (27), Belton et al. (30) observed that the Ti/O ratio indicated that the migrating species was a reduced oxide of Ti. 

Figure 1 shows the energy-particle distribution of Nb atoms at the substrate for two different voltages, a constant argon sputtering pressure of 2.6 Pa (20 mTorr),... 

Figure 12 gives the results of the AES depth profile of aluminum-polyethylene interface. At five different levels, the Ar sputtering was intervened, and A1 2p binding energy was measured by ESCA. Argon sputtering time, relative atomic concentration of carbon and aluminum at different levels are listed as follows ... 

Besides the chemical and radiochemical composition, other properties of the collected materials are also often of interest, such as the natine of the chemical compounds present in these substances. For example, the structure of oxide compounds after isolation from the base material or from the coolant is analyzed by X-ray diffractometry or by Mdssbauer spectrometry. Other microanalytical techniques can be directly applied to oxide layers deposited on surfaces, e. g. of steam generator tube sections. Examples in this field are Auger electron spectroscopy for the determination of element concentrations in micrometer areas and X-ray induced photoelectron spectroscopy for the determination of the chemical states of the individual elements. In order to obtain depth profiles over the thickness of the oxide layer, these techniques often are combined with an argon sputtering process (e. g. Schuster et al., 1988), which removes nanometer fractions from the swface prior to the next analysis step. By y spectrometry of the specimen after each sputtering step, the profile of the radionuclides in the oxide layer can also be determined. 

For the SEM investigation, specimens with surface areas of about 5x5 mm were taken from the modified wood fibers. The samples were coated with gold by argon sputtering. Subsequently surface morphology of the materials were investigated by SEM JSM 6400. 

Argon (sputtering) An inert (noble) gas used for sputtering because it is relatively inexpensive compared to other inert gases and has a reasonably high mass (40amu). 

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