Life Sciences Commons^™

Detection Of Small (5-15nm) Gold-Labelled Surface Antigens Using Backscattered Electrons, Paul Walther, Martin Müller

Scanning Electron Microscopy

The analysis of surface antigens by scanning electron microscopy represents a practicable alternative to replica techniques. It is generally observed that smaller markers provide for better labelling. In the SEM very small colloidal gold labels however are hardly discerned from contaminants or from surface structures of similar size. They are however unambiguously demonstrated by combining the surface information provided by the secondary electron signal and the material dependent signal provided by the backscattered electrons. A field emission SEM equipped with a highly sensitive single crystal backscattered electron detector allows the routine detection of 5 nm gold particles on biological surfaces. …

Some Applications Of The Electron Backscattering Diffusion Model, W. Czarczyński, Z. Radzimski

Scanning Electron Microscopy

Starting from a simple diffusion theory extended to oblique angles of incidence some empirical correction coefficients for electron backscattering have been found. These empirical coefficients have been used in calculations of backscattered electron surface density distribution, and good agreement with experimental data has been obtained.

Backscattering Of Electrons From Complex Structures, M. Kisza, Z. Maternia, Zbigniew Radzimski

Scanning Electron Microscopy

The backscattering of electrons from complex targets (for example, metal layer on a semi-infinite substrate with a polymer resist film above) has been studied both theoretically and experimentally. The experimental structures were exposed with an electron beam in a "spot mode". The experimental observations of developed disc radius vs. exposure time and metal layer thickness support the simple theory of scattering in such structures. The theory assumes that the backscattering causes enlarging of the exposed area by a constant value. This value is derived from the proposed scattering model based on the Archard's and Kanaya and Okayama's diffusion theories. The …

Electron Signal And Detector Strategy, L. Reimer

Scanning Electron Microscopy

The scintillator-photomultiplier combination (Everhart-Thornley detector) for detecting secondary and backscattered electrons (SE and BSE) has the best properties concerning signal-to-noise ratio and bandwidth as compared to other detectors (semiconductor detectors or channel plates).

Two opposite Everhart-Thornley detectors A and B are proposed for a better and reproducible angular selection of the SE. The field strength at the specimen is reduced either by a grid or ring electrode to separate the SE with regard to their exit momenta. This offers the possibility to record the signals A, B, A+B, and A-B. The signal A+B shows material and channelling contrast and the …

Interaction Of Electron Beam With The Target In Scanning Electron Microscope, Koichi Kanaya, Susumu Ono

Scanning Electron Microscopy

Based on the fundamental potential function of the power and exponential forms, a diffusion model of electron beams penetrating in a target has been proposed to take place throughout a hemisphere with a centre located at the most probable energy dissipation depth, related to the diffusion depth and the maximum energy dissipation depth, which is found to agree well with the empirical data of back-scattering coefficient as a function of the incident energy.

Based on the energy retardation power formula concerning the penetration and the energy loss of an electron probe into solid targets, the secondary electron emission yield has …

Direct Monte Carlo Simulation Of Kv Electron Scattering Processes-N(E) Spectra For Aluminum, Ryuichi Shimizu, Shingo Ichimura

Scanning Electron Microscopy

A Monte Carlo simulation of the scattering processes of kV electrons penetrating into aluminum was performed. The simulation is based on the use of different types of differential cross-sections for individual elastic and inelastic scattering: (i) the differential cross-sections derived by the partial wave expansion method for elastic scattering, (ii) Gryzinski's excitation function for inner-shell electron excitation, (iii) Streitwolf's excitation function for conduction electron excitation, (iv) Quinn's mean free path for plasmon excitation.

The main purpose of this work is to see how accurately the present direct Monte Carlo simulation describes the backscattered electrons from Al, which is the most …

Monte Carlo Simulation Of Electron Scattering In Resist Film/Substrate Targets, Kenji Murata

Scanning Electron Microscopy

First the fundamentals of resist modelling required to implement an analysis of developed resist patterns were studied, which represents the relationship between the energy deposited by incident electrons and the solubility characteristics of a positive or negative resist. Next, two models of single elastic scattering and fast secondary (knock-on) electron production were studied for Monte Carlo simulation of electron scattering in resist film/substrate targets, and the statistical errors of Monte Carlo results were evaluated. Finally, problems in electron beam lithography were investigated with the simulation. The exposure intensity distribution was studied with the two models. A comparison between Monte Carlo …