SEM Electron Channeling Pattern Stitching for Large-Area Defect Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for detecting crystalline defects in semiconductor materials, such as TEM, are limited by small imaging areas and cannot effectively assess defect distribution over larger regions, which is crucial for manufacturing quality control, as defects significantly impact device performance and reliability.
Innovation Solution
A method using a scanning electron microscope (SEM) to acquire partial images of electron channeling patterns from multiple positions, stitching them together to form a composite map, increasing the effective angular range and allowing for more accurate identification of crystal structure and orientation, enabling non-destructive high-throughput defect detection in larger areas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If transmission electron microscopy (TEM) is used to detect crystalline defects, then measurement precision is improved, but area of stationary object is limited
Solution Approach 1:
The patent divides the large-area defect detection task into multiple smaller imaging regions that are sequentially scanned and stitched together to form a comprehensive defect map, enabling both high precision and large area coverage
Solution Approach 2:
The patent transitions from two-dimensional TEM imaging to three-dimensional electron channeling pattern acquisition by tilting the sample and rotating the electron beam, thereby expanding the effective detection area while maintaining high measurement precision
2Area of stationary object
If scanning electron microscopy (SEM) is used for large area imaging, then area of stationary object is improved, but measurement precision deteriorates
Solution Approach 1:
The patent changes the imaging parameters by acquiring electron channeling patterns at multiple tilt angles and beam directions, then processes these multi-parameter datasets to achieve both large area coverage and high crystal orientation identification accuracy
3Measurement precision
If a small crystalline area is imaged, then measurement precision is improved, but quantity of substance is limited
Solution Approach 1:
The patent implements a nested imaging strategy where multiple high-resolution electron channeling patterns from different angular perspectives are combined to create a comprehensive view that effectively expands the detectable crystalline area while maintaining high pattern resolution
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 provides high-resolution characterization of crystalline defects over larger areas, comparable to TEM, while being non-destructive and suitable for manufacturing quality control, enabling the detection of misfit and threading dislocations in semiconductor materials with high spatial resolution.
Implementation Method 1
identifying a crystalline region on a device where an electronic channeling pattern is needed to determine the exact crystal orientation of the crystalline area with respect to the electron beam
Data Source
AI summary
A method for crystal analysis includes identifying a crystalline region on a device where an electronic channeling pattern is needed to be determined, acquiring a whole image for each of a plurality of different positions for the crystalline region using a scanning electron microscope (SEM) as the crystalline region is moved to different positions. Relevant regions are extracted from the whole images. The images of the relevant regions are stitched together to form a composite map of a full electron channeling pattern representative of the crystalline region wherein the electronic channeling pattern is provided due to an increase in effective angular range between a SEM beam and a surface of the crystal region.