Microscopy Sample Alignment Using Power Spectrum Tilt Estimation

Solution Overview

Problem

Conventional methods for aligning samples in microscopy systems, particularly for 3-dimensional structures, are inefficient and time-consuming due to the need for multiple sweeps to determine optimal tilt angles, especially when the initial configuration is far off the optimal values.

Innovation Solution

A method that determines the optimal second rotation angle based on the first rotation angle using additional information from the image's power spectrum, such as sharpness or anisotropy, reducing the need for a second sweep by establishing a mathematical relationship between the angles.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If multiple sweeps are performed to determine optimal tilt angles, then alignment precision is improved, but time consumption increases

Engineering Contradiction:

Improvealignment precisionVSAvoidtime consumption

Core Design Contradiction:

Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent performs a preliminary sweep to obtain initial tilt angle values before conducting the final precise alignment. This preliminary action provides a starting point that is closer to the optimal values, reducing the time needed for subsequent refinement while maintaining alignment precision.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent uses feedback from the preliminary sweep results to guide the final alignment process. By analyzing the trends and intermediate values obtained during the preliminary sweep, the system can adjust the search strategy and converge to optimal tilt angles more efficiently, reducing total time consumption.

Inventive Principle:

Principle #23Feedback

2Ease of operation

If initial configuration is far from optimal values, then ease of operation is improved, but time to reach optimal alignment increases

Engineering Contradiction:

Improveease of operationVSAvoidtime to reach optimal alignment

Core Design Contradiction:

Ease of operationVSLoss of time

Solution Approach 1:

The patent performs a preliminary sweep to obtain initial tilt angle values before conducting the final precise alignment. This preliminary action provides a starting point that is closer to the optimal values, reducing the time needed for subsequent refinement while maintaining alignment precision.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent transforms the alignment problem by introducing intermediate calculations and auxiliary functions that relate tilt angles to observable features. This dimensional transformation allows the system to navigate from arbitrary initial configurations to optimal alignment more efficiently by using intermediate reference frames.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Reliability

If conventional sweep methods are used, then measurement reliability is improved, but productivity decreases

Engineering Contradiction:

Improvemeasurement reliabilityVSAvoidproductivity

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent performs a preliminary sweep to obtain initial tilt angle values before conducting the final precise alignment. This preliminary action provides a starting point that is closer to the optimal values, reducing the time needed for subsequent refinement while maintaining alignment precision.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent performs a preliminary sweep that may be coarser or less precise than the final alignment sweep. By performing this partial action first, the system eliminates the need for multiple comprehensive sweeps, thereby increasing productivity while the final precise sweep ensures measurement reliability.

Inventive Principle:

Principle #16Partial or excessive action

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 approach significantly improves the efficiency of sample alignment in microscopy systems by determining optimal tilt angles more quickly and accurately, reducing the time required to achieve precise alignment.

Implementation Method 1

imaging, with a charged particle beam, the sample for each rotation angle

Methodology Applied

Scientific EffectCharged particle beam interaction: Electron Beam

Data Source

PatentUS12362137B2Automated sample alignment for microscopy

Publication Date: 2025.07.15 FEI CO

AI summary

Systems and methods for automated sample alignment for microscopy are described herein. In one aspect a method can include: rotating the sample along a first axis by each of a plurality of rotation angles; imaging, with a charged particle beam, the sample for each rotation angle; and determining a first rotation angle based on the image for each rotation angle, wherein the first rotation angle aligns the sample to the charged particle beam in relation to the first axis.