Rotatable TEM Grid Holder for Curtaining-Free FIB Thinning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional FIB milling processes result in curtaining effects during the preparation of semiconductor samples for TEM imaging due to heterogeneous structures, leading to impaired image quality.
Innovation Solution
A rotatable TEM grid holder system that allows the sample to be rotated 90° relative to the FIB, alternating orientations to mitigate curtaining effects by continuously adjusting the milling direction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If FIB milling is used to prepare semiconductor samples for TEM imaging, then sample thinning is achieved, but curtaining effects occur due to heterogeneous structures
Solution Approach 1:
The sample holder is designed to be rotatable, allowing dynamic adjustment of the sample orientation during FIB milling. This enables the user to rotate the sample by 90 degrees to change the milling direction, thereby avoiding curtaining effects that occur when milling along grain boundaries or layered structures. The dynamic repositioning capability transforms a static sampling process into an adaptable one that can overcome material heterogeneity.
Solution Approach 2:
The invention introduces an additional degree of freedom (rotational dimension) to the conventional FIB milling setup. By enabling rotation of the sample holder around the electron beam axis, the process transitions from fixed-direction milling to multi-directional milling, allowing the beam to approach the sample from different angular perspectives and thus avoid the harmful curtaining artifacts.
2Ease of operation
If conventional fixed orientation sample holder is used, then simple operation is maintained, but image quality is impaired due to curtaining
Solution Approach 1:
The sample holder incorporates a rotation mechanism that allows easy repositioning of the sample between different orientations. This dynamic capability enables operators to switch between 0度和90度 orientations as needed to optimize image quality without requiring complex sample preparation procedures, thus maintaining operational simplicity while improving imaging results.
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 clear TEM imaging by effectively removing curtaining effects and ensuring high-quality sample preparation for analysis.
Implementation Method 1
FIB systems use a finely focused beam of ions (usually gallium) that can be operated at high beam currents for site specific sputtering or milling of samples
Implementation Method 2
TEM allows analysis of the internal structure of a sample. Using a TEM, semiconductor device features are imaged from the interaction of the electrons with the sample as the beam is transmitted through the specimen
Data Source
AI summary
A rotatable transmission electron microscope (TEM) grid holder includes first and second legs orthogonally positioned with respect to each other. Each clamp holder leg is configured to be received within a hole in a main stage supporting the rotatable TEM grid holder. When the first leg of the clamp holder is affixed within the main stage, the sample has a first orientation with respect to the FIB, and when second leg of the clamp holder is affixed within the main stage, the sample has a second orientation with respect to the FIB, rotated 90° relative to the first orientation. The sample may be rotated back and forth between the first and second orientations multiple times as needed to produce a sample which may be clearly imaged by the TEM system, substantially free of curtaining effects.