Lithography Conduction Pin Force Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing lithography systems face challenges in connecting mask blanks to a reference potential due to inconsistent force application, which can result in either failure to penetrate thick resist or damage to thin resist surfaces, leading to dust generation and incomplete grounding.
Innovation Solution
A lithography system with variable force conduction pins and actuators that adjust the pressure of conduction pins against the material surface, allowing for precise connection to a reference potential regardless of resist thickness, using seesaw mechanisms and elastic members to minimize surface damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a constant force is applied to push the needle against the resist, then the needle can penetrate thick resist, but it will severely damage thin resist surfaces
Solution Approach 1:
The patent applies a spring mechanism to provide a dynamic, adjustable pressing force to the needle. The spring constant and pre-compression can be adjusted to match different resist thicknesses, allowing the needle to penetrate thick resist while applying gentler force on thin resist to avoid surface damage. This transforms the static constant force into a dynamic adjustable force.
Solution Approach 2:
The patent changes the force parameter by using a spring with adjustable stiffness or pre-compression. By modifying the spring parameters, the pressing force can be optimized for different resist thicknesses, resolving the contradiction between penetration capability and surface damage prevention.
2Reliability
If a strong force is applied to ensure needle penetration, then grounding is achieved, but dust is generated and surface scratches occur
Solution Approach 1:
The spring mechanism enables dynamic force adjustment, allowing the system to apply just enough force to achieve reliable grounding without excessive force that would generate dust or scratches. The force can be tuned to the minimum required for penetration.
Solution Approach 2:
The spring mechanism automatically adjusts the force based on the resistance encountered. When the needle encounters thick resist requiring more force, the spring compresses further to provide additional force, while for thin resist, the spring naturally limits the force to prevent damage, achieving self-regulation.
3Device complexity
If a constant pressing force is used, then the structure is simple, but it cannot adapt to various resist film thicknesses
Solution Approach 1:
By introducing a spring mechanism, the system gains adaptability to different resist thicknesses while maintaining relatively simple structure. The spring's elastic properties provide automatic adaptation without complex control systems, achieving a good balance between complexity and versatility.
Solution Approach 2:
The spring parameter (stiffness or pre-compression) can be adjusted to adapt to different resist thicknesses. This simple parameter change enables the same basic structure to handle various material conditions, improving versatility without significant structural complexity.
Data Source
Figure 1~2
Figure 3~5
Figure 6~7
AI summary
A lithography system for drawing patterns on a substrate (2) by irradiating the substrate with a beam of charged particles includes a stage for supporting the substrate, at least one conduction pin (16, 26) for connecting the substrate to a reference potential, and at least one actuator (12, 22) for moving the respective conduction pin. The at least one actuator (12, 22) is configured to move the respective conduction pin (16, 26) between a position where it contacts the substrate and a position where it does not contact the substrate. A resistance measurement circuit can measure the resistance between the first and second conduction pins, and if the resistance value is not less than a threshold value, the actuators are operated so as to lower the resistance value below the threshold value.