Electron Microscope Sample Holder Local Vacuum Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Charged particle beam apparatuses face challenges in maintaining a low vacuum environment around non-conductive samples, leading to charging issues and scattering of probing particles, which degrade image resolution, especially when observing samples containing water.
Innovation Solution
A sample holder with a vessel for a gas source and a cap member that creates a local low vacuum environment around the sample by vaporizing the gas source, reducing the risk of the sample colliding with the nozzle and allowing for efficient cooling while minimizing the scattering of probing particles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the entire sample chamber is kept at low vacuum atmosphere, then the sample charging is neutralized, but the probing particles collide with many gas molecules causing resolution deterioration
Solution Approach 1:
The patent applies local quality by creating a low vacuum atmosphere only in the specific region around the sample (within the nozzle structure) rather than throughout the entire sample chamber. This localized approach neutralizes sample charging where needed while maintaining high vacuum in other areas to prevent probing particle scattering and preserve resolution.
2Reliability
If gas is blown through a nozzle to the zone above the sample, then the local vacuum is maintained, but the sample may accidentally collide with the nozzle when moved
Solution Approach 1:
The patent implements nesting by placing the sample stage inside the nozzle structure. The sample stage is positioned within the hollow interior of the nozzle, allowing gas to flow around the sample from all directions while maintaining a safe distance that prevents collision during sample movement.
3Temperature
If a cooling stage is installed to cool the sample, then the saturation vapor pressure is lowered, but the device complexity increases
Solution Approach 1:
The patent achieves multi-functionality by designing the nozzle structure to serve multiple purposes: it delivers gas to maintain local vacuum atmosphere and simultaneously functions as a cooling structure through which coolant flows. This integrated design provides both atmosphere control and sample cooling without requiring separate cooling stages, thereby reducing device complexity.
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 solution enables easier maintenance of a low vacuum environment around the sample during cooling, improving image resolution and preventing charging, as demonstrated by reduced electron beam scattering and clearer surface structures in SEM images.
Implementation Method 1
a cap member which covers the vessel kept in a vacuum and a sample stage having a through hole. A sample to be observed is placed on the sample stage and kept at a low vacuum created by gas that is generated from the gas source evaporating or vaporizing
Data Source
AI summary
The present invention makes it possible, even when using an ordinary electron beam device (not an environment-controlled electron beam device), to create locally a low vacuum condition in the vicinity of a sample and cool said sample by means of a sample holder alone, without modifying the device or adding equipment such as a gas cylinder. The sample to be observed is placed in a sample holder provided with: a vessel that can contain a substance to serve as a gas source; and a through-hole in the bottom of a sample mount on said vessel. Via the through-hole, gas evaporating or volatilizing from the vessel is supplied to the sample under observation, thereby creating a localized low-vacuum state at or in the vicinity of the sample. Also, the heat of vaporization required for volatilization can be used to cool the sample.