Silicon {110} Calibration Sample for Electron Beam Angle Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing calibration samples with pyramidal shape patterns have a limited aspect ratio, making it difficult to accurately measure the incident angle of an electron beam, which is crucial for observing and measuring deep grooves and holes with high precision.
Innovation Solution
A calibration sample with a silicon single crystal substrate having a {110} plane as the upper surface and recess structures with {111} plane side surfaces and distinct crystal plane bottom surfaces, allowing for precise measurement of the incident angle by imaging and calculating the relative position and height difference between upper surface edges and bottom surface grooves.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a pyramidal shape pattern with aspect ratio of 1 or less is used, then the manufacturing precision is high, but the measurement precision of the incident angle is limited
Solution Approach 1:
The invention changes the geometric parameters of the calibration sample by creating a deep hole structure with aspect ratio greater than 1, departing from the conventional pyramidal shape with aspect ratio of 1 or less. This parameter change enables larger image variation with incident angle, thereby improving measurement precision while maintaining manufacturing precision through crystal anisotropic etching
Solution Approach 2:
The invention transitions from a two-dimensional pyramidal shape to a three-dimensional deep hole structure with vertical depth extending beyond the surface width. This dimensional change creates a structure where the bottom surface is out of plane with the upper surface, enabling enhanced sensitivity to incident angle changes in the depth dimension
2Measurement precision
If the aspect ratio of the pyramidal shape is increased to improve incident angle measurement, then the measurement precision improves, but the manufacturing precision deteriorates
Solution Approach 1:
The invention optimizes the geometric parameters by creating a deep hole structure where the depth exceeds the upper surface width, achieving aspect ratio greater than 1. This parameter optimization enables improved measurement precision while maintaining manufacturing precision through controlled crystal anisotropic etching processes
Solution Approach 2:
The invention applies different crystal plane orientations to different parts of the structure: {111} planes for the side surfaces providing precise angular relationships, and {311} planes for the bottom surface providing a distinct reference plane. This local differentiation of crystal planes enables both high manufacturing precision and improved measurement precision
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
Enables high-accuracy adjustment and measurement of the incident angle of the electron beam, improving the precision of observations and measurements of deep grooves and holes.
Implementation Method 1
accelerates electrons emitted from an electron source
Implementation Method 2
accelerates electrons emitted from an electron source
Implementation Method 3
concentrates the electrons onto a surface of the sample with an electrostatic lens or an electromagnetic lens
Implementation Method 4
concentrates the electrons onto a surface of the sample with an electrostatic lens or an electromagnetic lens
Implementation Method 5
a calibration sample is used in which a single crystal silicon having a (100) plane as an upper surface is subjected to crystal anisotropic etching to form a pyramidal shape
Data Source
AI summary
To implement a calibration sample by which an incident angle can be measured with high accuracy, an electron beam adjustment method, and an electron beam apparatus using the calibration sample. To adjust an electron beam using a calibration sample, the calibration sample includes a silicon single crystal substrate 201 whose upper surface is a {110} plane, a first recess structure 202 opening in the upper surface and extending in a first direction, and a second recess structure 203 opening in the upper surface and extending in a second direction intersecting the first direction, in which the first recess structure and the second recess structure each include a first side surface and a first bottom surface that intersects the first side surface, and a second side surface and a second bottom surface that intersects the second side surface, the first side surface and the second side surface are {111} planes, and the first bottom surface and the second bottom surface are crystal planes different from the {110} planes.