Quadrupole Corrector for Fifth-Order Aberrations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current particle-optical microscopes face limitations in resolution and probe current due to parasitic two-fold, fifth-order aberrations, which restrict their imaging capabilities, especially at higher opening angles.
Innovation Solution
The implementation of a spherical aberration corrector system that includes a first and second quadrupole field-generating component, with a third quadrupole positioned between them, to correct the fifth-order, two-fold aberrations in charged particle microscope systems, without affecting lower-order aberrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multipole correctors are used to correct spherical aberrations, then spherical aberrations up to order five can be corrected, but parasitic two-fold fifth-order aberrations remain uncorrected
Solution Approach 1:
The corrector system is divided into multiple multipole components (hexapole, octupole, and quadrupole elements) that each correct specific aberration terms. The parasitic two-fold fifth-order aberration is corrected by adding a dedicated quadrupole component to the existing multipole corrector system, segmenting the correction function across multiple specialized elements.
Solution Approach 2:
The invention changes the excitation parameters of the multipole corrector components to simultaneously correct multiple aberration types. By adjusting the excitation currents and field strengths of the hexapole, octupole, and quadrupole components, the system corrects both the primary spherical aberrations and the parasitic two-fold fifth-order aberration through coordinated parameter optimization.
2Ease of operation
If round lenses are used to direct electron beams, then the system is simple to operate, but positive spherical aberration coefficients restrict higher opening angles and inhibit resolution
Solution Approach 1:
Multipole corrector components are introduced as intermediary elements between the round objective lens and the specimen. These correctors generate corrective magnetic fields that compensate for the positive spherical aberration of the simple round lens, enabling high-resolution imaging at large opening angles while maintaining the operational simplicity of the primary lens system.
Solution Approach 2:
The invention changes the effective spherical aberration coefficient by adding corrective fields from multipole components. By adjusting the excitation parameters of the hexapole, octupole, and quadrupole elements, the system achieves negative effective spherical aberration coefficients that enable high-resolution imaging at large semi-opening angles without modifying the basic round lens structure.
3Measurement precision
If a third quadrupole is added to correct parasitic two-fold fifth-order aberrations, then resolution is enhanced at higher opening angles, but device complexity increases
Solution Approach 1:
The added quadrupole component is integrated into the existing multipole corrector system, serving multiple functions: correcting parasitic two-fold fifth-order aberrations, adjusting probe current, and working in conjunction with hexapole and octupole elements for comprehensive aberration correction. This multi-functionality reduces the need for separate dedicated components.
Solution Approach 2:
The invention merges the parasitic aberration correction function with the existing spherical aberration correction system by integrating quadrupole, hexapole, and octupole components into a single coordinated multipole corrector assembly. This combined approach corrects multiple aberration types simultaneously, reducing overall system complexity compared to separate correction systems.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration enhances the resolution of charged particle systems by effectively correcting parasitic two-fold, fifth-order aberrations, allowing for improved imaging capabilities at higher opening angles.
Implementation Method 1
a first corrective component that generates a first quadrupole field when a first excitation is applied to the first corrective component
Implementation Method 2
a second corrective component that generates a second quadrupole field when a second excitation is applied to the second corrective component
Implementation Method 3
a quadrupole that generates a third quadrupole field when a third excitation is applied to the quadrupole, wherein the third quadrupole field, in combination with at least the first quadrupole field and the second quadrupole field, corrects the fifth-order, two-fold aberration
Implementation Method 4
The third quadrupole field, in combination with at least the first quadrupole field and the second quadrupole field, corrects the fifth-order, two-fold aberration when the charged particle microscope is in use
Data Source
AI summary
Correctors for correcting two-fold, fifth-order parasitic aberrations in charged particle systems according to the present disclosure include a first corrective component that generates a first quadrupole field when a first excitation is applied to the first corrective component, and a second corrective component that generates a second quadrupole field when a second excitation is applied to the second corrective component. Correctors according to the present disclosure also include a quadrupole positioned between the second corrective component and the sample when used in the charged particle microscope system that generates a third quadrupole field. The third quadrupole field, in combination with at least the first quadrupole field and the second quadrupole field, corrects the fifth-order, two-fold aberrations when the charged particle microscope is in use.