Detector Array Cross-Talk Removal in Charged Particle Optics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing charged particle beam assessment systems face challenges in reducing cross-talk, which leads to decreased detection accuracy and image quality due to the detection of signal particles from areas assigned to different detector elements.
Innovation Solution
A charged particle-optical apparatus is designed to direct charged particles toward a sample, featuring a charged particle-optical device, a support for positioning the sample, a detector array for detecting signal charged particles, and a cross-talk remover that corrects detection signals independently of the sample's position relative to the beam paths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a detector array is used to detect signal particles from multiple beam areas simultaneously, then productivity is improved, but measurement precision deteriorates due to cross-talk between detector elements
Solution Approach 1:
The detector is divided into multiple detector elements, with each element corresponding to a specific beam area. This segmentation allows simultaneous detection from multiple beams, improving throughput while maintaining the ability to attribute signals to specific source areas through the cross-talk removal unit.
Solution Approach 2:
The cross-talk removal unit processes detection signals by referencing known cross-talk characteristics between detector elements. This feedback mechanism compensates for the interference caused by cross-talk, restoring measurement precision while preserving the high productivity enabled by the multi-element detector array.
2Measurement precision
If the distance between the detector array and the sample is reduced, then measurement precision is improved by reducing cross-talk, but device complexity increases due to tighter spatial constraints
Solution Approach 1:
The patent changes the spatial parameter (distance between detector and sample) to optimize performance. By reducing this distance, the system improves measurement precision through reduced cross-talk while accepting the trade-off of increased device complexity, which is managed through careful design of the detector array geometry and beam positioning.
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 effectively reduces cross-talk interference, enhancing the detection accuracy and image quality of the assessment systems by operating on detection signals independently of the sample's position, thereby improving the overall yield and throughput in semiconductor IC manufacturing.
Implementation Method 1
a charged particle-optical device configured to direct a plurality of beams of charged particles along respective beam paths toward a sample
Implementation Method 2
The interactions between the material structure of the sample and the electrons at the spot cause electrons to be emitted from the surface which may be referred as signal electrons or more generally signal charged particles
Implementation Method 3
a cross talk remover configured to correct the detection signals for cross talk by operating on the detection signals independently of position of the sample relative to the beam paths
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present disclosure relates to a charged particle-optical apparatus configured to direct charged particles toward a sample, the charged particle-optical apparatus comprising: a charged particle-optical device configured to direct a plurality of beams of charged particles along respective beam paths toward a sample; a support configured to support the sample and configured to position the sample relative to the beam paths; a detector array of detector elements configured to detect signal charged particles emitted from respective areas of a surface of the sample so as to generate respective detection signals; and a cross talk remover configured to correct the detection signals for cross talk by operating on the detection signals independently of position of the sample relative to the beam paths.