Substrate Edge Protective Film Coating for Patterned Wafer Coverage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods fail to appropriately form protective films at the peripheral edge portions of substrates with multiple patterning layers, leading to damage and contamination issues during cleaning and etching processes, particularly due to level differences and chip formation.
Innovation Solution
A method involving sequential application of a coating solution to the front and rear surfaces of a rotating substrate, followed by cleaning and additional coating to ensure comprehensive film formation at the edge portions, using specialized nozzles and controlled rotation speeds to prevent defects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a protective film is formed only on the front surface of the substrate, then the formation process is simple and fast, but the peripheral edge portions are not adequately protected, leading to damage and contamination during cleaning and etching processes
Solution Approach 1:
The coating process is segmented into three distinct steps: (A) front surface coating to form initial protective film, (B) rear surface cleaning to remove contaminants, and (C) rear surface coating to complete the protective film formation. This segmentation ensures comprehensive coverage of all substrate surfaces including peripheral edge portions while maintaining process control.
Solution Approach 2:
The rear surface cleaning step (B) is performed as a preliminary action before the final coating step (C). This preliminary cleaning removes contaminants and prepares the rear surface for optimal coating adhesion, ensuring the protective film forms correctly on the peripheral edge portions that would otherwise be exposed to damage.
2Manufacturing precision
If the substrate rotates at high speed during coating, then the coating solution distributes evenly, but the coating solution may not adequately reach the peripheral edge portions
Solution Approach 1:
The invention transitions from single-surface coating to multi-surface coating by adding rear surface treatment steps. The coating process operates in three dimensions: front surface initial coating, rear surface cleaning, and rear surface final coating. This dimensional expansion ensures the protective film reaches all peripheral edge portions that are inaccessible from front surface coating alone.
Solution Approach 2:
Instead of attempting to reach peripheral edges from the front surface, the invention approaches the problem from the opposite direction by coating the rear surface. The rear surface coater applies coating solution that flows onto the peripheral edge portions, effectively protecting areas that cannot be reached from the front.
3Productivity
If the protective film is formed before cleaning the rear surface, then the process sequence is simplified, but contaminants on the rear surface compromise film integrity
Solution Approach 1:
The rear surface cleaning step (B) is positioned as a preliminary action before the final coating step (C). This preliminary cleaning removes contaminants that would otherwise compromise the integrity of the protective film, ensuring high-quality film formation on the rear surface and peripheral edges.
Solution Approach 2:
The cleaning step (B) performs a preliminary anti-action by removing contaminants before the coating step (C) deposits the protective film. This prevents contaminants from being trapped under the film or causing adhesion failures, thereby protecting film integrity before the coating process completes.
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 approach effectively forms protective films at the substrate's edge portions, preventing damage and contamination, maintaining film integrity and reducing defects, while ensuring compatibility with existing patterning processes.
Implementation Method 1
supplying a coating solution for forming the protective film to the front surface of the substrate from a front-surface side coater located on the front surface side of the substrate while rotating the substrate to form the protective film at the peripheral edge portion of the substrate
Implementation Method 2
supplying a cleaning solution to a rear surface of the substrate from a cleaning solution supplier located on the rear surface side of the substrate while rotating the substrate to clean the rear surface and a peripheral end surface of the substrate
Data Source
AI summary
A method for forming a protective film at a peripheral edge portion of a substrate having patterning layers on a front surface includes: (A) supplying a coating solution for forming the protective film to the front surface of the substrate from a front-surface side coater while rotating the substrate to form the protective film at the peripheral edge portion of the substrate; (B), after the (A), supplying a cleaning solution to a rear surface of the substrate from a cleaning solution supplier while rotating the substrate to clean the rear surface and a peripheral end surface of the substrate; and (C), after the (B), supplying the coating solution to the rear surface of the substrate from a rear-surface side coater while rotating the substrate to form the protective film on the rear surface and the peripheral end surface of the peripheral edge portion of the substrate.