Optical Apparatus for Plasma Spatial Resolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current measuring apparatuses for plasma processes, such as Langmuir probes and other electrode-based sensors, are not suitable for real-time analysis of plasma density and radical distribution due to their invasive nature, which can disrupt chemical reactions and lack spatial resolution for precise process control in semiconductor and plasma generator applications.
Innovation Solution
An optical apparatus with a light collection lens, aperture stops, and a pinhole to limit depth of focus, combined with a spectrum unit for wavelength-based intensity measurement, and an align unit to ensure proper alignment, allowing for non-invasive, real-time analysis of plasma emission spectra with improved spatial resolution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If electrode-based measuring apparatuses (Langmuir probe) are inserted into the plasma chamber, then electrical characteristics can be measured, but the measurement precision of spatial distribution of chemical species deteriorates due to invasive disruption of chemical reactions
Solution Approach 1:
The patent replaces the mechanical/electrode-based measurement system with an optical measurement system. The optical apparatus uses a light collection lens to receive optical emission spectrum from plasma, aperture stops to block out-focused and in-focused light, and a pinhole to limit depth of focus, thereby measuring spatial distribution of chemical species without physical insertion into the plasma chamber, avoiding disruption of chemical reactions
Solution Approach 2:
The patent introduces optical emission spectrum as an intermediary to indirectly measure the spatial distribution of chemical species. Instead of directly inserting electrodes into plasma, the system captures light emitted by plasma and analyzes its spectral characteristics to infer chemical species distribution, using optical signals as a non-invasive mediator
2Use of energy by moving object
If optical emission spectrum is collected without spatial filtering, then light intensity can be measured, but the spatial resolution deteriorates due to inclusion of out-focused light from accumulated light sources
Solution Approach 1:
The patent segments the light collection process into distinct functional components: a light collection lens for gathering light, aperture stops for spatial filtering, and a pinhole for depth of focus control. This segmentation allows the system to collect sufficient light while simultaneously filtering out unwanted out-focused light, achieving both high light collection efficiency and high spatial resolution
Solution Approach 2:
The patent applies local quality by creating a focused imaging area with high spatial resolution through the pinhole aperture, while other regions contribute to overall light collection. The aperture stops and pinhole provide localized spatial filtering at critical positions in the optical path, ensuring that only light from the specific region of interest reaches the detector
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 precise measurement of plasma density and radical distribution with improved spatial resolution, enhancing process uniformity and control in semiconductor and plasma generator applications without disrupting chemical reactions.
Implementation Method 1
a light collection lens configured to receive an optical emission spectrum emitted from an object area through the window of the plasma generator
Implementation Method 2
a pinhole disposed at an imaging area of the light collection lens to limit depth of focus
Data Source
AI summary
An optical apparatus for plasma includes a light collection lens provided to receive optical emission spectrum from plasma, a first aperture stop disposed between the light collection lens and the plasma to block out-focused light, a second aperture stop disposed between the light collection lens and an imaging area of the light collection lens to block in-focused light, and a pinhole disposed at the imaging area of the light collection lens to limit depth of focus.