Focused Ion Beam Apparatus Curtain Effect Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Focused ion beam processing of fine structures, such as semiconductor devices, is hindered by the curtain effect due to varying etching rates caused by shadowing, making it difficult to suppress processing streaks, especially when the sample is tilted excessively or insufficiently.
Innovation Solution
A focused ion beam apparatus with a sample stage that is movable in horizontal and height directions, equipped with memory to store three-dimensional data and a display controller to show virtual positional relationships between the sample table and the focused ion beam, allowing for precise control and visualization of beam direction before actual irradiation, enabling effective suppression of the curtain effect.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the sample is tilted to suppress the curtain effect, then processing quality improves, but it is difficult to determine the appropriate tilt angle without excessive trial and error
Solution Approach 1:
The system performs preliminary simulation calculations using stored three-dimensional data of the sample, sample table, and instrument positions to predict the curtain effect before actual processing. This allows the optimal tilt angle to be determined in advance without excessive trial and error during actual processing.
Solution Approach 2:
The system creates a virtual copy of the physical system through three-dimensional data models of the sample, sample table, and instruments. Simulation processing is performed on this virtual model to predict processing outcomes and determine optimal parameters before applying them to the actual sample.
2Measurement precision
If three-dimensional data on the sample is acquired for each measurement to display precise beam direction, then accuracy improves, but work efficiency decreases due to repeated data acquisition
Solution Approach 1:
The system acquires and stores three-dimensional data on the sample in advance, before the actual measurement or processing. This pre-acquired data is then reused for simulation and display purposes, eliminating the need to repeat data acquisition for each measurement while maintaining precision.
Solution Approach 2:
The stored three-dimensional data serves multiple functions: it is used for simulation processing to predict curtain effects, for displaying the positional relationship between the beam and sample, and for determining optimal processing parameters. This multi-use of the same data increases productivity without sacrificing accuracy.
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 setup allows for accurate determination and suppression of the curtain effect, improving processing efficiency by allowing for appropriate tilting of the sample stage to minimize processing streaks and ensuring precise control over the focused ion beam's direction, thus enhancing the quality of the processing outcome.
Implementation Method 1
a focused ion beam lens column configured to irradiate a sample with a focused ion beam
Data Source
AI summary
A focused ion beam apparatus (100) includes: a focused ion beam lens column (20); a sample table (51); a sample stage (50); a memory (6M) configured to store in advance three-dimensional data on the sample table and an irradiation axis of the focused ion beam, the three-dimensional data being associated with stage coordinates of the sample stage; a display (7); and a display controller (6A) configured to cause the display to display a virtual positional relationship between the sample table (51v) and the irradiation axis (20Av) of the focused ion beam, which is exhibited when the sample stage is operated to move the sample table to a predetermined position, based on the three-dimensional data on the sample table and the irradiation axis of the focused ion beam.