Charged Particle Beam Shutter Mechanism for Vacuum Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In charged particle beam devices, the frequent replacement of valve bodies due to pressure differences between vacuum spaces leads to deterioration of the seal function and contamination of the electron source, particularly when gas components and moisture pass through the beam optical axis, necessitating a solution that maintains cleanliness and extends the lifespan of the shutter member.
Innovation Solution
A charged particle beam device with a partition between the charged particle source and specimen stages, incorporating a shutter mechanism that moves between locations on and off the optical axis to block gas components without pressing against other members, and a control device that manages the valve between the specimen and exchange chambers to maintain a clean environment and reduce replacement frequency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If the valve body is strongly pressed to maintain pressure difference between vacuum spaces, then the pressure difference is maintained, but the contact surface deteriorates and replacement frequency increases
Solution Approach 1:
The patent introduces a shutter member as an intermediary component that blocks the passage of gas components between vacuum spaces without requiring strong pressing contact. The shutter member moves to block the opening, maintaining pressure difference through positioning rather than continuous strong contact pressure, thereby reducing wear and extending service life.
2Stress or pressure
If the valve body is strongly pressed to maintain pressure difference, then the pressure difference is maintained, but replacement frequency increases
Solution Approach 1:
The shutter member acts as a mediator that can be quickly positioned to block gas passage, enabling rapid response to pressure difference requirements without the time-consuming process of adjusting strong pressing forces. This reduces device stop time while maintaining pressure differential.
3Ease of operation
If gas components pass through the beam optical axis, then the vacuum chamber is accessible, but the electron source becomes contaminated
Solution Approach 1:
The patent segments the vacuum system into distinct regions separated by the shutter member. When the shutter is in the blocking position, it creates a segmentation that prevents gas components from the accessible vacuum chamber region from reaching the electron source region, thereby preventing contamination while allowing chamber accessibility.
4Object-affected harmful factors
If the shutter member is positioned to block gas components, then cleanliness is maintained, but the shutter member may contact and deteriorate
Solution Approach 1:
The shutter member is designed as a non-contacting intermediary that blocks gas components through its positioning rather than through strong contact with the partition. This intermediary function allows it to maintain cleanliness of the electron source while minimizing contact wear and extending its own service life.
Data Source
AI summary
The objective of the present invention is to provide a charged particle beam device such that a tip part can be effectually maintained in a clean state, while the frequency of valve body replacements is also reduced. To achieve the objective, a charged particle beam device is offered, comprising: a partition that is positioned between a charged particle source-side vacuum space and a specimen stage-side vacuum space, said partition further comprising an opening for a charged particle beam to pass through; a driver mechanism that moves a shutter member between a first location within the optical axis of the charged particle beam and a second location outside the optical axis of the charged particle beam; and a control device that controls the driver mechanism. The first location is a location wherein the shutter member is distanced from the partition, and the control device carries out a control that opens a valve between the specimen chamber and the exchange chamber when the shutter member is in a state of being located in the first location.