Rotatable OES Module for Plasma Uniformity Monitoring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current OES devices have limited detection capabilities for plasma uniformity in semiconductor fabrication, as they can only monitor a restricted range of plasma light angles, which may not adequately cover the wafer surface, leading to potential abnormalities in plasma processes going undetected.
Innovation Solution
The integration of a rotatable rotation module with a first surface blocking part of the plasma light and a second surface allowing light communication through openings, enabling the OES device to monitor plasma light at various angles, thereby expanding the detectable range and ensuring comprehensive plasma uniformity analysis.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If a fixed OES device is used to monitor plasma light, then the device structure is simple, but the detection range is limited and cannot cover the entire wafer surface
Solution Approach 1:
The patent applies the dynamics principle by making the OES device rotatable around the wafer. Instead of using multiple fixed devices, a single OES device rotates to different angular positions to monitor plasma light from various locations on the wafer surface, thereby expanding the detection range while maintaining relatively simple device structure.
Solution Approach 2:
The patent introduces rotational movement around the wafer, adding an angular dimension to the detection capability. The OES device moves from a single fixed position to multiple angular positions around the wafer, effectively expanding the monitoring area from a limited viewpoint to comprehensive circumferential coverage.
2Illumination intensity
If the rotation module is made transparent to plasma light, then light transmission is maximized, but stray light and interference cannot be blocked
Solution Approach 1:
The rotation module applies local quality by having different optical properties in different regions. The first surface (facing the viewport) is transparent to maximize plasma light transmission, while the second surface (facing the OES device) includes blocking portions to prevent stray light and interference from reaching the detector, thus addressing both requirements locally.
Solution Approach 2:
The rotation module is segmented into different functional regions: a transparent first surface for light entry, blocking portions on the second surface for interference rejection, and openings for light passage. This segmentation allows each region to perform its specific function optimally without compromising the other requirements.
3Measurement precision
If the OES device monitors plasma from a single angle, then the device structure is simple, but plasma uniformity across the wafer cannot be accurately determined
Solution Approach 1:
The system uses rotational dynamics to enable the OES device to monitor plasma light from multiple angular positions around the wafer. By rotating to different angles and comparing the plasma light intensities detected at each position, the system can accurately determine plasma uniformity across the entire wafer surface with a single versatile device.
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 configuration allows for real-time monitoring of plasma uniformity across a wider area, enabling early detection of abnormalities and adjustments to process variables, thereby improving the reliability and consistency of semiconductor fabrication processes.
Implementation Method 1
a rotation module coupled to a viewport of a chamber, the rotation module configured to transmit plasma light generated in the chamber
Implementation Method 2
the first surface is configured to block a part of the plasma light
Implementation Method 3
includes a first opening through which an inside of the rotation module is configured to be exposed to a part of the plasma light
Implementation Method 4
a spectroscope configured to separate the plasma light and analyzes intensities of corresponding wavelengths
Data Source
AI summary
A plasma processing apparatus is provided. The plasma processing apparatus includes a chamber configured to perform a plasma process on a wafer, a viewport configured to transmit plasma light generated in the chamber, a rotation module coupled to the viewport to be rotatable around a rotation axis, and an OES (Optical Emission Spectroscopy) device which is coupled to the rotation module and configured to receive the plasma light, wherein the rotation module includes a first surface facing the viewport and a second surface facing the OES device, wherein the first surface is configured to block a part of the plasma light, and includes a first opening through which an inside of the rotation module is configured to be exposed to a part of the plasma light, and wherein the second surface includes a second opening configured to be in light communication with the first opening.