Substrate Processing Liquid Recirculation With Backside Gas Shielding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing substrate processing methods generate particles on the second main surface opposite to the first main surface when reusing processing liquids, and cause fluctuations in the concentration of these liquids, affecting their performance and reusability.
Innovation Solution
A substrate processing apparatus and method that includes a holding unit, liquid supply units, a collection unit, a circulation path, a gas supply unit, and a control unit, which controls the supply of processing liquids and gases to both main surfaces of the substrate to prevent mixing and vapor wrap-around, thereby suppressing particle generation and concentration fluctuations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of substance
If processing liquid is supplied to the first main surface and then reused, then cost reduction is achieved, but particles are generated on the second main surface and concentration fluctuations occur
Solution Approach 1:
The substrate processing is divided into two distinct sides: the first main surface receives the processing liquid for chemical treatment, while the second main surface receives gas supply for drying. This segmentation prevents the processing liquid from contacting the second surface, thereby avoiding particle generation while allowing the processing liquid to be reused on the first surface.
Solution Approach 2:
A gas (such as nitrogen or clean air) is introduced as an intermediary substance to the second main surface. This gas acts as a mediator that prevents processing liquid droplets from wrapping around and contacting the second surface, thereby preventing particle generation while maintaining the reusability of the processing liquid on the first surface.
2Loss of substance
If processing liquid is reused through circulation path, then cost reduction is achieved, but concentration fluctuations occur affecting liquid performance
Solution Approach 1:
The processing system is segmented into two separate zones: the first main surface zone where processing liquid is applied and reused, and the second main surface zone where only gas is supplied. This segmentation prevents contamination of the processing liquid by substrate materials from the second surface, maintaining concentration stability while enabling reuse.
Solution Approach 2:
Gas supplied to the second main surface acts as a protective intermediary that prevents processing liquid from wrapping around and mixing with contaminants from the substrate背面. This maintains the chemical composition and concentration of the processing liquid, enabling stable reuse through the circulation path.
3Object-affected harmful factors
If gas is supplied to the second main surface when processing liquid is supplied to the first main surface, then particle generation is suppressed, but device complexity increases
Solution Approach 1:
The gas supply unit serves multiple functions: it prevents particle generation on the second main surface, controls the drying process, and maintains the reusability of processing liquid. By consolidating these functions into a single gas supply system, the apparatus achieves effective particle suppression without excessive complexity.
Solution Approach 2:
Gas is introduced as a simple intermediary substance that can be supplied through existing gas distribution infrastructure. This approach prevents particle generation without requiring complex additional components, as the gas acts as a straightforward barrier against liquid wrap-around while using standard apparatus elements.
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
Effectively suppresses particle generation and concentration fluctuations on the second main surface, allowing reuse of expensive processing liquids like BHF, reducing costs and waste, while maintaining liquid performance.
Implementation Method 1
The control unit supplies the gas to the second main surface when supplying the processing liquid to be returned to the liquid supply unit by the circulation path to the first main surface
Data Source
AI summary
A substrate processing apparatus includes a holding unit, a liquid supply unit, a collection unit, a circulation path, a gas supply unit, and a control unit. The holding unit holds a substrate. The liquid supply unit supplies a processing liquid to a first main surface of the substrate held by the holding unit. The collection unit collects the processing liquid used for processing the substrate. The circulation path returns the processing liquid collected by the collection unit back to the liquid supply unit. The gas supply unit supplies a gas to a second main surface to the substrate held by the holding unit in a direction opposite to the first main surface. The control unit supplies the gas to the second main surface when supplying the processing liquid to be returned to the liquid supply unit by the circulation path to the first main surface.