Nano Beam Diffraction Strain Sensitivity via Ion Milling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional nano beam diffraction (NBD) analysis techniques face limitations in achieving strain sensitivity below 0.1% due to surface damage from focused ion beam (FIB) sample preparation, which introduces artifacts and reduces technique sensitivity.
Innovation Solution
A system and method that includes additional milling of the FIB-prepared TEM sample using a broad beam ion mill to remove the damaged surface layer, exposing an underlying pristine surface for analysis, combined with high-resolution TEM camera imaging to enhance sensitivity to less than 0.1%.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If FIB sample preparation is used, then sample extraction and initial preparation is achieved, but surface damage is introduced that reduces NBD strain sensitivity
Solution Approach 1:
The sample preparation process is divided into two distinct stages: first, FIB preparation to extract and initially thin the sample; second, ion mill treatment to remove the damaged surface layer. This segmentation allows each process to be optimized independently, with the ion mill specifically targeting the removal of FIB-induced damage to restore measurement precision.
Solution Approach 2:
The harmful damaged surface layer created by FIB preparation is selectively removed through ion mill treatment. This extraction of the damaged portion eliminates the source of measurement errors while preserving the underlying pristine material for accurate NBD analysis.
2Measurement precision
If additional ion mill treatment is applied, then strain sensitivity is improved to below 0.1%, but device complexity and process time increase
Solution Approach 1:
The ion mill device is integrated into the existing FIB system, allowing it to perform dual functions: the same system that prepares the sample also removes the damaged layer. This multi-functionality avoids the need for completely separate preparation and treatment systems, thereby limiting the increase in device complexity.
Solution Approach 2:
The ion mill treatment is performed as a preliminary step before NBD measurement to ensure the sample surface is free from damage. By preparing the sample in advance with the correct surface quality, the actual measurement process is simplified and does not require additional complex equipment during data acquisition.
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 approach improves NBD strain sensitivity by 15-20% compared to conventional methods, achieving a sensitivity of 0.08-0.07%, effectively overcoming the limitations of surface damage and enhancing characterization capabilities for semiconductor devices.
Implementation Method 1
a broad beam ion mill for milling the TEM sample to remove a surface portion of the TEM sample
Implementation Method 2
performing NBD analysis on the milled TEM sample to acquire diffraction data
Implementation Method 3
The spacing between the diffraction spots in a diffraction pattern directly correlate to the spacing between crystallographic planes in the crystalline material generating the pattern
Data Source
AI summary
A system for performing diffraction analysis, includes a mill for removing a surface portion of a sample, and an analyzer for performing diffraction analysis on the milled sample.