Source scanning electron microscope

Scanning electron microscope image of a Ti DL with 25 pm diameter holes (reference bar indicates 100 pm). (Reprinted from K. D. Fushinobu et al. Journal of Power Sources 158 (2006) 1240-1245. With permission from Elsevier.)... 

In Table I, well-known techniques are listed by excitation source and measured emission. Although mentioned there, x-ray fluorescence (XRF), electron microprobes (EMP), and scanning electron microscopes (SEM) will be excluded here because they are not sensitive to the surface, which is generally considered to be 2.5-5.0 nm deep. 

X-ray powder diffraction patterns were obtained on oriented film specimens [7] (2 to 45° 2 , Philips PW 1120, monochromatized CuKa radiation, continuous peak registration). BET surface area and the pore volume distribution were determined from Nj adsorption-desorption isotherms at 77 K (degassing at 393 K, lO" mbar, 5h Sorptomatic 1900, Carlo Erba Instruments). The IR-spectra were recorded on KBr wafers [4] with a Specord 80M spectrometer. The XPS (X-ray photoelectron spectroscopy) spectra were obtained with VG ESCALAB 200 MKII spectrometer equipped with a twin anode AIKa source (1486 eV). The thermogravimetric (TGA) analyses were carried out with a Setaram TG 85 thermobalance at a heating rate of 6 K min in a helium flow of 30 ml min . The chromium content of the samples was determined by EPMA (JEOL 840 scanning electron microscope) with energy dispersive spectrometer (EDS, Tracer Northern) and by AAS (atomic absorption spectroscopy, Perkin Elmer 3030) analyses. 

A system generating a primary ion beam consists of three main parts ion source, ion filter and deflector as schematically illustrated in Figure 8.5. The ion source produces primary ions with a certain kinetic energy. The ion filter purifies the primary ions and rejects unwanted ions in the primary ion beam. The purified ions are condensed to a focused beam using an electromagnetic lens. The deflector makes the focused ion beam raster on the sample surface in two orthogonal directions its function is similar to the electron beam deflector in the scanning electron microscope (SEM). 

The lower limit for short lifetimes in this technique is determined by the optical excitation source turn-off time to about 0.1 gs. For shorter lifetimes steady-state diffusion length measurements are more suitable. The diffusion leyth is related to the recombination lifetime by the equation L l/(Dt ). Suitable techniques are surface photovoltage and scanning electron microscope electron beam induced current. They lend themselves to lifetimes down to the nano-second range. 

---