Life Sciences Commons^™

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 Scattering And Energy Losses As A Function Of The Incident Energy: Application To Chemical Analysis, Bernard Jouffrey

Scanning Electron Microscopy

This paper gives a rapid overview on the use of the energy losses suffered by an incident electron beam. General approximations are remembered. Then some recent results on inner shell excitations as a function of energy (in high voltage electron microscopy) are given, and the problem of thick samples is rapidly discussed.

The problem of the observation of sensitive materials in electron microscopy is discussed. A simple model is proposed to determine some orders of magnitude on the inelastic mean free path and the elementary volume of defects created during the irradiation with electrons of different energies. This model can …

Monte Carlo Calculations For Electron Microscopy, Microanalysis, And Microlithography, David F. Kyser

Scanning Electron Microscopy

The methodology of Monte Carlo simulation for electron scattering and energy dissipation in solid targets is reviewed. The basic concepts of single and multiple elastic scattering models are compared, and the continuous energy loss model for inelastic scattering is discussed. Some new developments in Monte Carlo simulation are reviewed, including improvements in the elastic scattering model and discrete models for inelastic scattering. A variety of practical applications of Monte Carlo calculations in the fields of electron microscopy, electron probe microanalysis, and electron beam lithography are reviewed. The Monte Carlo computer program listings available in the literature are also described.

Monte Carlo Electron Trajectory Calculations Of Electron Interactions In Samples With Special Geometries, Dale E. Newbury, Robert L. Myklebust

Scanning Electron Microscopy

Implementing a Monte Carlo simulation for application to electron sample interactions requires use of accurate treatments of elastic and inelastic scattering. In formulating a Monte Carlo simulation, careful testing must be carried out to ensure that the calculation yields sensible and useful results. A suitable testing procedure includes calculation of (1) electron backscatter coefficients as a function of atomic number, including any necessary adjustment of scattering parameters; (2) backscatter coefficients as a function of specimen tilt; (3) backscatter and transmission coefficients for thin foils; (4) backscattered electron energy distributions; (5) electron spatial distributions; and (6) x-rays, including x-ray depth distributions, …

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 …

Monte Carlo Simulation Of Spatial Resolution Limits In Electron Beam Lithography, David F. Kyser

Scanning Electron Microscopy

Computer simulation of high energy primary electron scattering and subsequent generation of "fast" secondary electrons in thin film targets is demonstrated with Monte Carlo techniques. The hybrid model of Murata et al. (1981) is utilized to calculate the generation and subsequent spatial trajectory of each secondary electron in the target. The 3-dimensional spatial distribution of energy dissipation by such "fast" secondary electrons is shown to be the fundamental resolution limit for electron beam lithography with high-voltage beams (100 keV) and thin film polymer targets. The dependence of resolution on beam voltage and film thickness is presented, and quantitative comparison is …