Build reliable electron-transport predictions for semiconductor metrology, surface analysis, and nanostructured materials.
Cross sections · energy loss · electron yield
Electron Transport, Scattering, and Emission
Physics libraries and Monte Carlo studies of elastic and inelastic scattering, backscattering, secondary-electron emission, and photoelectron escape.
Goal
Why this problem matters
The research is organised by scientific question rather than career stage, so the methods and results form one continuous programme.
Understand how cross sections, energy-loss functions, material composition, and geometry shape measurable electron yields.
Method
How the problem is approached
- 01
Transport
Sample elastic deflection and inelastic energy-loss events along Monte Carlo electron trajectories.
- 02
Elastic model
Use Salvat's ELSEPA code to calculate Mott elastic cross sections across 384 combinations of nuclear charge distribution, electron density, exchange, correlation-polarisation, and solid-state atomic potentials; this code was used, not authored in this work.
- 03
Inelastic model
Compare full Penn, super-extended Mermin, and Levine–Louie inelastic formalisms with four available optical ELF datasets, giving a broader catalogue of 12 inelastic combinations.
- 04
Quantify
Combine the elastic and inelastic model spaces with reported work functions and electron-affinity values to quantify sensitivity and identify defensible model choices.
- 05
Benchmark
Benchmark simulated yields and backscattering coefficients against experimental records across bulk and structured targets.
Results
What the programme has established
- Result 01Quantified secondary-electron emission from silicon across the full physical-model space used in the study.
- Result 02Computed emission and backscattering behaviour for germanium and Cr, Co, and Pd solids.
- Result 03Modelled CD-SEM signals from wave-type structures and photoelectron transport in non-spherical core–shell particles.
- Result 04Used uncertainty quantification to identify which elastic and inelastic combinations were physically defensible and which dominated the spread.
- Result 05Extended the programme to spatially resolved secondary-electron emission in multiwall carbon nanotubes; that manuscript remains in preparation.
Scientific animation
The mechanism, made visible
This interactive figure is an explanatory schematic. It is clearly separated from the peer-reviewed quantitative figures below.
Conceptual visualization
Electron transport through a structured surface
A primary electron enters a layered surface, scatters through the material, and may leave as a backscattered electron or generate lower-energy secondary electrons.
Ready
- Primary electronIncident or backscattered trajectory
- Elastic scatteringChanges the primary-electron direction
- Inelastic scatteringTransfers energy and can create a secondary excitation
- Secondary electronLower-energy electron leaving the solid
- Material geometryLayered surface represented explicitly
- View
- Electron–solid interaction
- Current event
- Secondary and backscattered emissionIllustrative process stage
- Physics
- Transport + emission
- Numbers
- Not simulated hereNo illustrative path is presented as measured data
Conceptual transport views based on Monte Carlo electron–solid interaction and scattering workflows; geometry and paths are explanatory rather than measured.
Evidence
Figures from the research
Each figure is placed beside the scientific programme it supports rather than repeated in a separate gallery.
Publications
Related scholarly work
Monte Carlo study of the electron emission yields of germanium
H. I. Imtiaz, Y. B. Zou, S. F. Mao, M. S. S. Khan, Z. J. Ding
Electron backscattering coefficients for Cr, Co, and Pd solids: a Monte Carlo study
H. I. Imtiaz, M. S. S. Khan, A. Hussain, S. F. Mao, Y. B. Zou, Z. J. Ding
An extensive theoretical quantification of secondary-electron emission from silicon
M. S. S. Khan, S. F. Mao, Y. B. Zou, D. B. Lu, B. Da, Y. G. Li, Z. J. Ding
A theoretical characterization method for non-spherical core–shell nanoparticles by XPS
J. M. Gong, M. S. S. Khan, B. Da, H. Yoshikawa, S. Tanuma, Z. J. Ding
Influence of energy-loss function on the Monte Carlo simulated electron backscattering coefficient
H. Chen, Y. B. Zou, S. F. Mao, M. S. S. Khan, K. Tőkési, Z. J. Ding
CD-SEM characterization of smoothly varying wave structures with a Monte Carlo simulation
M. S. S. Khan, L. H. Yang, X. Deng, S. F. Mao, Y. B. Zou, Y. G. Li, H. M. Li, Z. J. Ding
Monte Carlo simulation of secondary-electron emission from wave-type structure
M. S. S. Khan, Y. B. Zou, C. Li, Z. J. Ding
Use of a model-based library in critical-dimension measurement by CD-SEM
Y. B. Zou, M. S. S. Khan, H. M. Li, Y. G. Li, W. Li, S. T. Gao, L. S. Liu, Z. J. Ding