Reaction Assembly Countermass Vibration Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Vibration generated by wafer and reticle stage mover assemblies in exposure apparatuses leads to alignment errors and reduced accuracy in positioning semiconductor wafers relative to reticles, affecting the manufacturing of high-density semiconductor wafers.
Innovation Solution
A stage assembly with a reaction assembly that includes a base countermass and transverse countermasses, which counteract reaction forces and pitching moments, allowing for precise positioning by transferring reaction forces to the countermasses rather than the stage base, thereby minimizing vibration impact.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If stage movers are used to precisely position the wafer and reticle, then positioning accuracy is improved, but reaction forces generated by the movers cause vibration that degrades alignment accuracy
Solution Approach 1:
The patent introduces a reaction assembly including a base countermass and transverse countermasses that act as counterweights to absorb and neutralize the reaction forces generated by the stage movers. The base countermass moves along the primary axis to counteract longitudinal reaction forces, while transverse countermasses move perpendicular to the primary axis to counteract pitching moments and rotational forces, thereby eliminating vibration that would otherwise degrade alignment accuracy.
Solution Approach 2:
The reaction assembly serves as an intermediary mechanism between the stage movers and the stage base. Instead of allowing reaction forces to directly transmit to the stage base and cause vibration, the reaction assembly intercepts these forces through guided countermasses and dissipates them, preventing the harmful transmission of vibration to the positioning system.
2Force
If reaction forces are transferred to the stage base, then the stage mover can generate sufficient force for precise positioning, but the stage base experiences vibration that reduces alignment accuracy
Solution Approach 1:
The patent extracts the harmful reaction forces from the stage base system by introducing a separate reaction assembly. The base countermass and transverse countermasses are specifically designed to absorb and neutralize reaction forces and pitching moments, removing these destabilizing forces from the stage base and maintaining system stability while preserving the positioning force generation capability.
3Ease of manufacture
If the stage assembly structure is simplified, then ease of manufacture is improved, but the ability to counteract reaction forces and pitching moments is reduced
Solution Approach 1:
The reaction assembly is segmented into distinct functional components: a base countermass for handling primary axis reaction forces, and transverse countermasses for handling pitching moments and rotational forces. Each countermass is guided by dedicated linear guides, creating modular, independently functioning units that are relatively simple to manufacture and assemble while collectively providing comprehensive vibration counteraction capability.
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
The solution enhances the accuracy of positioning semiconductor wafers and reticles, improving the quality and precision of semiconductor wafer manufacturing by effectively canceling out reaction forces and pitching moments, leading to higher quality semiconductor wafers.
Implementation Method 1
the base countermass is coupled to the reaction component so that reaction forces from the stage mover are transferred to the base countermass to move the base countermass along the first axis
Implementation Method 2
the first transverse countermass is coupled to the base countermass so that movement of the base countermass along the first axis causes the first transverse countermass to move along the first transverse axis
Data Source
AI summary
A reaction assembly 18 for a stage assembly 10 that moves a device 26 along a first axis includes a base countermass 40 and a first transverse countermass 42. The stage assembly 10 includes a stage 14 and a stage mover 16 that includes a moving component 38 that is coupled to the stage 14 and a reaction component 36 that is secured to the base countermass 40. The first transverse countermass 42 is guided to allow for movement along a first transverse axis 50 and the first transverse countermass 42 is coupled to the base countermass 40 so that movement of the base countermass 40 along the first axis causes the first transverse countermass 42 to move along the first transverse axis 50.