Movable Barrier Liquid Immersion Member for Exposure Apparatus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In liquid immersion exposure apparatuses, liquid leakage or residual liquid on substrates can lead to exposure failures, resulting in defective device manufacturing.
Innovation Solution
A liquid immersion member and exposure apparatus design that includes a first and second member to form a liquid immersion space, with the second member being movable to control liquid flow and pressure variations, preventing liquid from escaping or remaining on the substrate during exposure processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a liquid immersion space is formed between the projection system and substrate, then exposure quality is improved, but liquid may flow out or remain on the substrate causing exposure failure
Solution Approach 1:
The barrier member is designed to be movable in the vertical direction, allowing it to dynamically adjust its position. The driving unit moves the barrier member to follow the substrate's movement during exposure, maintaining optimal liquid immersion while preventing liquid leakage. This dynamic adjustment resolves the contradiction by adapting the barrier position to real-time operational conditions.
Solution Approach 2:
The system incorporates a driving unit that receives control signals to adjust the barrier member's position based on substrate movement. This feedback mechanism ensures the barrier member maintains the correct position relative to the substrate, preventing liquid flow-out while preserving the liquid immersion exposure environment, thus improving both reliability and exposure quality.
2Reliability
If the barrier member is made movable to control liquid flow, then liquid leakage is prevented, but device complexity increases
Solution Approach 1:
The barrier member serves multiple functions: it confines liquid in the immersion space, prevents liquid from reaching the substrate, and dynamically adjusts to substrate movement. The driving unit integrates control functions to manage barrier position. This multi-functionality reduces the need for separate components, thereby limiting the increase in device complexity while achieving reliable liquid confinement.
3Quantity of substance
If liquid is confined in a fixed space, then liquid flow is controlled, but substrate movement causes liquid to remain on substrate
Solution Approach 1:
The barrier member transitions from a fixed to a movable structure, capable of vertical displacement. The driving unit actuates the barrier member to follow the substrate's movement trajectory, ensuring the liquid immersion space remains properly positioned. This dynamic configuration prevents liquid from remaining on the substrate during movement while maintaining appropriate liquid quantity in the immersion space, thus preserving exposure accuracy.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A liquid immersion member (4A) forms, in an exposure apparatus (EX1), liquid immersion space (LS) through which exposure light (EL) emitted from an optical member (3) passes, the liquid immersion member includes: a first member (41) that is disposed at at least part of a space around the optical member and that includes a first lower surface (4111) facing an object (5, 51, 52, 6, 61) which is movable below the optical member; and a movable second member (42) that includes a second lower surface (4211) which is disposed at outer side than the first lower surface viewed from optical axis (AX) of the optical member and which faces the object and a third lower surface (4221) which is disposed at inner side than the second lower surface viewed from the optical axis and whose at least part is disposed above at least part of the first lower surface.