Charged Particle Microscopy Segmentation for Faster EDS Element Mapping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for examining samples using charged particle microscopes are limited by the need for time-consuming data acquisition and sacrifice spatial resolution for chemical accuracy in energy dispersive x-ray spectroscopy (EDS) analysis, particularly in determining the concentration of elements.
Innovation Solution
A method that dynamically adjusts the size of segments based on the number of similar spectral emissions required for confidently identifying each chemical element, using different base spectral number values for varying elements, allowing for rapid and accurate acquisition of spectral information.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If EDS detectors record x-rays at each pixel location during scanning, then chemical accuracy is improved, but spatial resolution deteriorates due to time-consuming data acquisition
Solution Approach 1:
The patent segments the scanned area into discrete regions and assigns different base spectral number values to different chemical elements. This allows the system to process spectral data in manageable segments rather than requiring complete spectral acquisition at every pixel location, thereby reducing overall data acquisition time while maintaining chemical accuracy through targeted spectral analysis.
Solution Approach 2:
The patent implements local quality by allowing different chemical elements to have different base spectral number values assigned to them. This means that the spectral acquisition strategy is optimized locally for each element type present in the sample, enabling faster acquisition for elements with lower base spectral number values while maintaining accuracy for elements requiring higher values, thus resolving the time-accuracy tradeoff.
2Measurement precision
If counts from several close pixels are binned together, then chemical accuracy is improved, but spatial resolution deteriorates
Solution Approach 1:
The patent introduces dynamic adaptability by allowing the base spectral number value to vary depending on the chemical element being analyzed. This dynamic parameter enables the system to adjust the degree of pixel binning on-the-fly based on element-specific requirements, rather than applying a fixed binning strategy across all pixels. Elements with higher base spectral number values can tolerate more aggressive binning, while those with lower values maintain stricter spatial fidelity.
Solution Approach 2:
The patent changes the parameter of base spectral number value from a fixed constant to a variable parameter that depends on the chemical element. This parameter change allows the system to optimize the balance between spatial resolution and chemical accuracy for each element individually, resolving the contradiction by making the binning strategy element-specific rather than uniformly applied.
3Measurement precision
If the electron beam dwells longer at each analysis point, then spectral information quality is improved, but scanning speed deteriorates
Solution Approach 1:
The patent performs preliminary action by pre-assigning base spectral number values to different chemical elements before the actual scanning and spectral acquisition process. This preliminary configuration allows the system to know in advance how much spectral data is needed for each element type, enabling optimized dwell time calculations and preventing unnecessary prolonged dwelling at pixels where sufficient spectral information has already been acquired for that element.
Solution Approach 2:
The patent implements feedback mechanisms where the spectral counts accumulated at each pixel are continuously monitored against the element-specific base spectral number values. When the accumulated counts meet or exceed the required base spectral number value for a particular element, the system can reduce or terminate further spectral acquisition for that element at that location, thereby maintaining spectral quality while improving scanning speed through adaptive, feedback-driven dwell time control.
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
Enables more rapid and accurate determination of chemical elements with varying spatial resolution based on their concentration, improving the graphical representation of sample composition.
Implementation Method 1
Irradiation of a sample by a scanning electron beam precipitates emanation of 'auxiliary' radiation from the sample, in the form of secondary electrons
Implementation Method 2
backscattered electrons
Implementation Method 3
X-rays
Implementation Method 4
cathodoluminescence (infrared, visible and/or ultraviolet photons)
Implementation Method 5
each backscattered electron is amplified as it creates many electron-hole pairs in a semiconductor detector
Implementation Method 6
In a process called 'energy dispersive x-ray spectroscopy' or 'EDS', the energies of x-rays coming from the sample in response to the electron beam are measured and plotted in a histogram to form a material specific spectrum
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method of examining a sample using a charged particle microscope is provided. The method comprises providing a charged particle beam and scanning said beam over an area (50) of the sample, detecting spectral emissions from the sample in response to the charged particle beam being scanned over the area (50) of the sample, and identifying a first plurality of substantially similar spectral emissions (54a). A first chemical element (54a') is determined that is associated with said first plurality of substantially similar spectral emissions (54a). A first base spectral number value associated with said determined first chemical element (54a') is provided. Said first base spectral number value is related to the number of similar spectral emissions that are required for confidently determining said first chemical element (54a'). The first base spectral number value is used for dividing at least a part of the scanned area of the sample into a first number of first segments (154a; 61). The method includes providing a graphical representation (150) of the sample, wherein said graphical representation (150) includes said first chemical element (54a') and corresponding first segments (154a; 61).