Submicron particle analysis by the Auger microprobe (FE-SAM)

Monte Carlo Simulation of SEM and SAM Images

“…It has been shown that utilization of the low primary beam voltage of 3 kV has the advantage of reducing the edge effect in analyzing a 0.7 m μ TiN particle on a steel (Forsyth & Bean, 1994;Olson et al, 1993) and an Au bar (0.6 m μ high and 1.0 m μ wide) on a Si substrate (Tuppen & Davies, 1985). While it has also been pointed out that (Ito et al, 1996) electrons with high energy will penetrate deep into the particle to reduce edge effect. The edge effect can dramatically degrade spatial resolution (El Gomati et al, 1988;Shimizu & Everhart, 1978;Tuppen & Davies, 1985) because AE from substrate can be detected even when the primary beam is impacted at the particle.…”

“…For submicron Au particles (e.g. 100 d > nm at 8 keV), the usual edge enhancement effect (caused by higher-energy SEs that passing through the side surface of a particle and hitting the substrate to generated extra AE signals of the substrate (Ito et al, 1996)) and shadowing/shading effect (shadowing of the AEs on their emission path by a particle leads to a decrease of the substrate signals at the edge (Shimizu & Everhart, 1978)) become obvious in Cu-Auger line-scans as observed experimentally (Ito et al, 1996). These effects due to the excitation and emission process of AEs have been well expounded (El Gomati et al, 1988;Shimizu & Everhart, 1978;Tuppen & Davies, 1985;Umbach & Brunger, 1989;Wells, 1974).…”

“…To comprehend the problems, many efforts (Cowley & Liu, 1993;El Gomati et al, 1978;El Gomati et al, 1979;Hembree et al, 1991;Hembree & Venables, 1992;Ito et al, 1996;Janssen & Venables, 1978;Liu & Cowley, 1993;Liu et al, 1993;Tuppen & Davies, 1985) have been done theoretically by using a MC simulation method and experimentally since ten years ago. Experiments were aimed to improve the spatial resolution for surface step and small particles deposited on substrates under different beam conditions (Cowley & Liu, 1993;Hembree et al, 1991;Hembree & Venables, 1992;Ito et al, 1996;Janssen & Venables, 1978;Liu & Cowley, 1993;Liu et al, 1993).…”

“…Experiments were aimed to improve the spatial resolution for surface step and small particles deposited on substrates under different beam conditions (Cowley & Liu, 1993;Hembree et al, 1991;Hembree & Venables, 1992;Ito et al, 1996;Janssen & Venables, 1978;Liu & Cowley, 1993;Liu et al, 1993). The edge effect observed on a rough edge, which is caused by primary electrons when passing through the side surface of a step/particle and then hitting the surrounding substrate surface to generate extra Auger signals of the substrate elements, and the backscattering effect, which is resulted by primary electrons that backscatter to the sample surface to generate extra AEs of the surface elements, are mainly discussed for systems of thin film step on substrates by simulations of Auger line scans using MC methods (El Gomati et al, 1978;El Gomati et al, 1979;Tuppen & Davies, 1985).…”

Lateral Resolution of Imaging Surface-Analytical Instruments as SIMS, AES and XPS: Application of the BAM-L200 Certified Reference Material and Related ISO Standards

“…Edge effects were discussed in the literature based on Monte Carlo simulation or for submicron particle analysis by the Auger microprobe [2,3]. Another issue is that a systematic underestimation of Dx-(100-x) occurs when the plateau length Lpl left and right to the (chemical) edge is too short (cf.…”