In-situ Ion Beam Metrology via Optical Emission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The use of Faraday devices for ion beam characterization is compromised by electrically insulating components in the processing chamber, leading to reduced precision and accuracy in determining ion beam parameters such as height, uniformity, and central angle.
Innovation Solution
A system and method utilizing a test workpiece with a detection pattern, where the ion beam parameters are measured using an optical emission spectrometer (OES) or a workpiece bias power supply, allowing for in-situ characterization without Faraday devices, with detection patterns configured to determine beam height, uniformity, and central angle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If Faraday devices are used to measure ion beam parameters, then measurement capability is provided, but measurement precision deteriorates due to electrically insulating components in the processing chamber
Solution Approach 1:
The patent replaces the traditional Faraday device (electrical measurement system) with an optical measurement system using OES. The ion beam impact on the detection pattern generates optical emissions that are detected by the OES system, substituting electrical current measurement with optical signal detection to eliminate interference from insulating components.
Solution Approach 2:
The detection pattern serves as an intermediary between the ion beam and the OES measurement system. The detection pattern converts ion beam impact into optical emissions that can be detected, acting as a mediator that enables indirect measurement while avoiding direct electrical contact that would be affected by insulating components.
2Reliability
If Faraday devices are used for ion beam characterization, then beam parameters can be determined, but reliability is reduced due to contamination risks from insulating materials
Solution Approach 1:
The patent eliminates the electrical measurement path that is susceptible to contamination by substituting it with an optical measurement system. The OES system detects optical emissions from the detection pattern, avoiding direct electrical contacts that would be affected by contaminating insulating materials in the chamber.
3Measurement precision
If traditional Faraday device arrays are used, then ion beam parameters can be measured, but device complexity increases and immediate feedback is not achieved
Solution Approach 1:
The patent extracts the measurement function from the complex Faraday device array and concentrates it into a single detection pattern on the workpiece holder. This single integrated component performs the measurement function that previously required multiple separate Faraday devices, simplifying the overall system architecture.
Solution Approach 2:
The detection pattern serves multiple measurement functions simultaneously - it can determine ion beam height, uniformity, and central angle all through a single optical measurement system, replacing the need for multiple specialized Faraday devices for different parameter measurements.
4Area of stationary object
If Faraday devices are positioned close to insulating components, then space utilization is improved, but measurement accuracy deteriorates
Solution Approach 1:
The patent substitutes the electrical measurement system with an optical one, allowing the detection pattern to be positioned anywhere in the ion beam path without electrical interference concerns. The OES system detects optical emissions regardless of the detection pattern's position relative to insulating components, enabling flexible spatial arrangement.
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 and accurate characterization of ion beam parameters at the point of impact, reducing contamination risks and providing immediate feedback, while avoiding the limitations of Faraday devices in the presence of insulating materials.
Implementation Method 1
the amount of current striking the detection pattern may be measured using an optical emission spectrometer (OES) system
Implementation Method 2
the amount of current from the ion beam striking the detection pattern
Data Source
AI summary
A system for determining various parameters of an ion beam is disclosed. A test workpiece may be modified to incorporate a detection pattern. The detection pattern may be configured to measure the height of the ion beam, the uniformity of the ion beam, or the central angle of the ion beam. In certain embodiments, the amount of current striking the detection pattern may be measured using an optical emission spectrometer (OES) system. In other embodiments, a power supply used to bias the workpiece may be used to measure the amount of current striking the detection pattern. Alternative, the detection patterns may be incorporated into the workpiece holder.