Gas Cluster Ion Beam Composition Control via Feedback Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current gas cluster ion beam processing apparatuses lack the ability to precisely control the composition of gas mixtures used to form gas cluster ion beams, which is crucial for applications like semiconductor doping and film deposition, as they cannot independently control the flows of individual gases and often require costly chemical analysis to ensure the correct gas mixture is used.
Innovation Solution
Incorporating a gas analyzer capable of sensing and analyzing the relative concentrations of gas constituents in the gas mixture, allowing for real-time monitoring and control of the gas mixture composition, with the ability to adjust gas flows to maintain the required ratios, thereby ensuring accurate processing conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If gas mixture composition is not precisely controlled, then device complexity is reduced, but manufacturing precision deteriorates
Solution Approach 1:
The patent implements a feedback control system where the actual gas mixture composition is measured and compared to the target composition, and the mass flow controllers are adjusted based on this comparison to maintain precise gas mixture ratios. This closed-loop feedback mechanism ensures manufacturing precision without requiring overly complex manual control systems.
Solution Approach 2:
The patent replaces manual mechanical adjustment of gas flows with automated electronic control through mass flow controllers and a computer system. This substitution of mechanical control with electronic automation simplifies the overall device complexity while improving precision of gas mixture composition control.
2Measurement precision
If chemical analysis is performed to verify gas mixture, then measurement precision is improved, but loss of time increases
Solution Approach 1:
The patent enables continuous monitoring of gas mixture composition through the feedback system, allowing the GCIB process to proceed without interruption. The real-time measurement and control eliminate the need for periodic chemical analysis that would stop the process, thus maintaining continuous useful action while ensuring measurement precision.
Solution Approach 2:
The patent introduces an intermediary sensing system that provides real-time gas mixture composition data without requiring direct chemical analysis. This intermediary measurement system allows for rapid verification of gas mixture ratios without the time-consuming nature of traditional chemical analysis methods.
3Ease of operation
If mass flow controllers are used to mix gases, then ease of operation is improved, but reliability deteriorates due to potential mixing errors
Solution Approach 1:
The patent implements feedback control where the actual gas mixture composition is continuously measured and used to adjust the mass flow controllers. This feedback mechanism compensates for potential mixing errors and maintains reliable gas mixture accuracy while preserving the ease of operation provided by automated mass flow control.
Solution Approach 2:
The system performs self-correction of gas mixture ratios through the feedback loop, automatically detecting and compensating for deviations without external intervention. This self-service capability enhances reliability by ensuring accurate gas mixture composition while maintaining ease of operation through automated control.
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 solution enables precise control of the gas mixture composition, preventing mis-processing of semiconductor wafers and other products by ensuring the correct gas cluster ion constitution, thereby improving the accuracy and reliability of surface modification processes.
Implementation Method 1
a gas analyzer capable of sensing and analyzing the relative concentrations of gas constituents in the gas mixture
Implementation Method 2
Cooling, which results from the expansion in the jet, causes gas in the jet to condense into clusters
Implementation Method 3
a pressurized source gas is ejected through a nozzle into a vacuum, forming a supersonic gas jet
Implementation Method 4
The clusters can be ionized by electron bombardment or other means, permitting them to be formed into directed beams
Data Source
AI summary
Methods and apparatus for controlling a gas cluster ion beam formed from a plurality of process gases in a gas mixture. The methods and apparatus involve measuring gas analysis data relating to the composition of the gas mixture and modifying the irradiation of the workpiece in response to the detected parameter. The gas analysis data can be derived from samples of the composition of the gas mixture flowing from a gas source to the gas cluster ion beam apparatus or samples of the residual gases inside the vacuum vessel of the gas cluster ion beam apparatus.