Rotating Substrate Wetting Flow to Prevent Lower-Side Contamination
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Solution Overview
Problem
The formation of a vortex on the substrate during the cleaning process leads to contamination of the lower surface due to the rotation of the substrate, causing treatment solution to flow onto the lower surface and contaminate it.
Innovation Solution
A method and apparatus where fluid is supplied to the lower surface of a rotating substrate before and during the treatment solution application, using a wetting solution and gas to prevent contamination by forming a liquid film on the upper surface, which includes a wetting solution supply operation and a gas supply operation to create an airflow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the substrate is rotated at high speed to form a liquid film and volatilize solvent, then cleaning efficiency is improved, but the lower surface of the substrate becomes contaminated due to vortex formation
Solution Approach 1:
A fluid supply unit supplies fluid to the lower surface of the substrate before the treatment solution is supplied to the upper surface. This preliminary action creates a protective fluid layer that prevents treatment solution and mist from contaminating the lower surface during high-speed rotation and vortex formation.
Solution Approach 2:
Fluid acts as an intermediary substance between the treatment solution environment and the lower surface of the substrate. The fluid layer mediates by preventing direct contact between contaminants (treatment solution and mist) and the lower surface, allowing high-speed rotation to proceed without contamination.
2Manufacturing precision
If treatment solution is supplied to the upper surface during substrate rotation, then particles are captured and cleaned, but treatment solution flows to the lower surface causing contamination
Solution Approach 1:
The substrate treatment process is segmented into separate zones: the upper surface receives treatment solution for particle capture and cleaning, while the lower surface receives fluid supply for contamination prevention. This spatial segmentation allows both functions to occur simultaneously without interference or cross-contamination.
Solution Approach 2:
Fluid is supplied to the lower surface in advance and continuously during treatment solution supply to the upper surface. This preliminary protective action ensures that even if treatment solution or mist reaches the lower surface area, the pre-established fluid barrier prevents contamination.
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
Improves cleaning efficiency and prevents contamination of the substrate's lower surface by solidification or curing of the treatment solution, ensuring effective particle capture and removal.
Implementation Method 1
forming a liquid film of the treatment solution by volatilizing the volatile solvent in the treatment solution
Implementation Method 2
a gas supply operation of supplying gas forming an airflow to the lower surface of the substrate
Data Source
AI summary
Disclosed is a method of processing a substrate, the method including: a fluid supply operation of supplying fluid to a lower surface of a rotating substrate; a treatment solution supply operation of supplying a treatment solution containing a polymer and a volatile solvent to an upper surface of the rotating substrate; after the treatment solution supply operation, a liquid film forming operation of forming a liquid film of the treatment solution by volatilizing the volatile solvent in the treatment solution and solidifying or curing the treatment solution; and after the liquid film forming operation, a liquid film removing operation of removing the liquid film of the treatment solution by supplying a removal solution to the substrate, in which the fluid supply operation, the supply of the fluid starts before the liquid film forming operation.