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method. Ultimate lithographic resolution is limited by the interaction of the incident particle with the recording medium. Improving
this resolution remains a topic of current research.
Alternatively, a focused ion beam can selectively remove material
from a bulk sample, enabling fabrication of useful structures. A
focused electron beam can be used to simultaneously in the same
(dual beam) instrument to produce an SEM image, thus enabling
in situ observation and endpoint detection of this removal process.
Yet another important example of inelastic scattering is the production of a host of particle species in a high energy particle accelerator. This process takes place by the conversion of kinetic energy
of the incident particle to mass of the products. This has been used
in ongoing research to deduce the most fundamental properties of
elementary particles and their interactions.
An enormous literature exists describing the interaction of charged
particles with matter. Rather than attempt a comprehensive summary, we will confine our attention to two-particle scattering. This
is the most basic of all scattering processes, and is derived from
first principles of physics in a straightforward way. Two-particle
scattering forms the basis of many of the interactions of charged
particle beams with matter in practical instruments.
The central problem in the following sections is to calculate the
momentum and energy transfer resulting from two-particle scattering. Closely related to this is the intensity as a function of scattering angle measured relative to the direction of the incident particle,
where this represents the relevant measurable quantity. Although
the process is fundamentally quantum mechanical, a great deal of
intuitive understanding can be gained by first studying the classical description, and then proceeding to the quantum mechanical
description.
method. Ultimate lithographic resolution is limited by the interaction of the incident particle with the recording medium. Improving
this resolution remains a topic of current research.
Alternatively, a focused ion beam can selectively remove material
from a bulk sample, enabling fabrication of useful structures. A
focused electron beam can be used to simultaneously in the same
(dual beam) instrument to produce an SEM image, thus enabling
in situ observation and endpoint detection of this removal process.
Yet another important example of inelastic scattering is the production of a host of particle species in a high energy particle accelerator. This process takes place by the conversion of kinetic energy
of the incident particle to mass of the products. This has been used
in ongoing research to deduce the most fundamental properties of
elementary particles and their interactions.
An enormous literature exists describing the interaction of charged
particles with matter. Rather than attempt a comprehensive summary, we will confine our attention to two-particle scattering. This
is the most basic of all scattering processes, and is derived from
first principles of physics in a straightforward way. Two-particle
scattering forms the basis of many of the interactions of charged
particle beams with matter in practical instruments.
The central problem in the following sections is to calculate the
momentum and energy transfer resulting from two-particle scattering. Closely related to this is the intensity as a function of scattering angle measured relative to the direction of the incident particle,
where this represents the relevant measurable quantity. Although
the process is fundamentally quantum mechanical, a great deal of
intuitive understanding can be gained by first studying the classical description, and then proceeding to the quantum mechanical
description.