Focused Particle Beam Imaging with Pressure-Staged Gas Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing devices for imaging and processing samples using focused particle beams face challenges such as beam quality degradation, contamination of sensitive components, and reduced resolution due to the introduction of process gases, which disrupt the high vacuum environment and lead to scattering of the particle beam.
Innovation Solution
A device with a sample chamber configured for medium vacuum processing, a pressure adjustment unit that limits pressure increase to a factor of 10 or less, and a detection unit operating in a high vacuum environment to prevent contamination and maintain beam quality, allowing for high local process gas concentration and precise imaging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If process gas is introduced into the vacuum chamber to enable local chemical reactions, then the reaction efficiency and processing capability are improved, but the particle beam is scattered by gas particles causing beam quality degradation and resolution reduction
Solution Approach 1:
The vacuum chamber is divided into two distinct pressure zones: a high vacuum region for the particle beam column and source, and a medium vacuum region for the sample processing area. This segmentation allows process gas to be introduced locally at the sample without affecting the beam quality in the high vacuum region, thereby resolving the contradiction between processing capability and beam resolution.
Solution Approach 2:
Different vacuum conditions are applied to different spatial regions of the system. The sample processing zone operates at medium vacuum (10^-3 to 10^-1 mbar) to enable efficient chemical reactions with process gas, while the beam column maintains high vacuum (10^-9 to 10^-11 mbar) to preserve beam quality. This local differentiation of vacuum conditions allows both requirements to be satisfied simultaneously.
2Productivity
If process gas is introduced into the vacuum chamber to enable local chemical reactions, then the reaction efficiency is improved, but contamination and damage to sensitive components in the particle beam column occur
Solution Approach 1:
The system is segmented into a high vacuum region containing sensitive components (particle source, beam column, detectors) and a medium vacuum region where process gas is introduced. A physical barrier (flange connection) separates these regions, preventing process gas from reaching and contaminating sensitive components while allowing efficient processing in the medium vacuum region.
Solution Approach 2:
A pressure stage tube acts as an intermediary element between the high vacuum and medium vacuum regions. This tube with a small inner diameter (0.5-2 mm) and specific length-to-diameter ratio creates a pressure gradient that allows process gas to exist in the sample region without penetrating into the high vacuum region, thus protecting sensitive components from contamination.
3Adaptability or versatility
If process gas is introduced into the vacuum chamber, then the local chemical reaction capability is improved, but the high vacuum environment is disrupted leading to increased pressure and beam scattering
Solution Approach 1:
The vacuum system is segmented into pressure stages, allowing the sample processing region to operate at medium vacuum (10^-3 to 10^-1 mbar) suitable for chemical reactions, while the beam column maintains high vacuum (10^-9 to 10^-11 mbar). This pressure segmentation enables chemical reaction capability without disrupting the vacuum environment required for beam transport.
Solution Approach 2:
The problem is solved by adding a spatial dimension to the vacuum pressure distribution. Instead of a uniform vacuum pressure throughout the system, different axial regions operate at different pressure levels. The pressure varies along the beam axis, with high vacuum upstream and medium vacuum downstream, enabling both beam quality and chemical reactivity.
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
The solution enables high-quality imaging and processing of samples with minimal contamination of sensitive components, maintaining beam stability and resolution while allowing for efficient local chemical reactions.
Implementation Method 1
a particle beam typically interacts with a sample to be analyzed and/or processed
Implementation Method 2
The focused particle beam is scattered at the particles of the process gas and/or its reaction products
Implementation Method 3
at least one pressure adjustment unit through which the particle beam and the particles emanating from the sample pass and which is configured to limit a pressure increase
Implementation Method 4
at least one detection unit which is arranged within the at least one column and which is configured to detect particles emanating from the sample
Implementation Method 5
at least one gas line system which terminates at the outlet of the focused particle beam from the column and which is configured to locally provide at least one process gas at the sample
Data Source
AI summary
The present application relates to a device for imaging and processing a sample using a focused particle beam, comprising: (a) at least one particle source which is configured to create a particle beam in an ultrahigh vacuum environment; (b) at least one sample chamber which serves to accommodate the sample and which is configured to image the sample in a high vacuum environment and process the sample in a medium vacuum environment; (c) at least one column which is arranged in a high vacuum environment and which has at least one particle-optical component configured to shape a focused particle beam from the particle beam and direct said focused particle beam at the sample; (d) at least one detection unit which is arranged within the at least one column and which is configured to detect particles emanating from the sample; (e) at least one gas line system which terminates at the outlet of the focused particle beam from the column and which is configured to locally provide at least one process gas at the sample with a pressure such that the focused particle beam is able to induce a particle beam-induced local chemical reaction for processing the sample; and (f) at least one pressure adjustment unit through which the particle beam and the particles emanating from the sample pass and which is configured to limit a pressure increase caused at the at least one detection unit as a result of processing the sample to a factor of 10 or less, preferably to a factor of 5 or less, more preferably to a factor of 3 or less, and most preferably to a factor of 2 or less, without impeding access of the particles emanating from the sample to the at least one detection unit.