Optical Substrate Holding Detection in Wet Processing Cups
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing substrate processing apparatuses face challenges in determining the holding state of a substrate within a cup configuration, as traditional optical detection methods are not applicable and are not suitable for wet or corrosive environments.
Innovation Solution
The apparatus includes a projector and light receiver configuration where the detection light path passes through substrate surrounding members but not the substrate, allowing for flexible placement and operation, including within the cup, using LED light with a wavelength that penetrates resin materials but not silicon substrates, and continuous state determination during processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the light projector and light receiver are disposed outside the cup, then the optical detection can be performed, but the detection cannot be performed when the cup is at a raised position surrounding the substrate
Solution Approach 1:
The patent transitions the optical detection system from external placement to internal placement within the cup structure. By disposing the light projector and light receiver inside the cup, the system enables continuous optical detection regardless of the cup's vertical position, resolving the limitation where external detection failed when the cup surrounded the substrate.
Solution Approach 2:
The light projector and light receiver are nested within the cup structure, allowing the optical detection system to be integrated into the substrate processing apparatus. This nested configuration enables the detection system to operate independently of the cup's position, as the light path remains unobstructed whether the cup is raised or lowered.
2Adaptability or versatility
If the light projector and light receiver are disposed within the cup, then the detection can be performed at any cup position, but the wet and corrosive environment within the cup affects the detection components
Solution Approach 1:
The patent employs a transparent window or film structure within the cup that allows optical detection while protecting the light projector and light receiver from direct contact with the processing liquid. This barrier maintains the integrity of the detection components in the wet and corrosive environment while enabling continuous optical monitoring.
Solution Approach 2:
A transparent intermediate structure (window or film) is introduced between the processing liquid and the optical detection components. This intermediary allows light to pass through for substrate holding state determination while preventing the corrosive liquid from damaging the projector and receiver.
3Measurement precision
If traditional optical detection methods are used, then the substrate holding state can be determined, but the method is not applicable to cup configurations with substrate processing within the cup
Solution Approach 1:
The patent repositions the optical detection system from an external arrangement to an internal arrangement within the cup. This spatial reconfiguration allows the light path to pass through the substrate holding member and substrate, enabling precise detection of the substrate holding state while being compatible with cup-based processing configurations.
Solution Approach 2:
The integrated optical detection system within the cup serves multiple functions: it determines substrate holding state, operates during liquid processing, and maintains compatibility with various cup-based substrate processing configurations. This universal design eliminates the need for separate detection systems for different processing modes.
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 configuration enhances the flexibility of substrate holding state determination and timing, preventing substrate damage by ensuring proper holding before and during processing, even in challenging environments.
Implementation Method 1
the detection light radiated from the projector has a wavelength which penetrates the substrate surrounding member but does not penetrate the substrate
Data Source
AI summary
Provided is a substrate processing apparatus in which flexibility of disposing a device configured to determine a holding state of a substrate and the flexibility of timing of determining the holding state are enhanced. The substrate processing apparatus includes a light projector configured to radiate detection light toward a region where a substrate may exist when the substrate is held by a substrate holding member and a light receiver configured to receive the detection light radiated from the light projector. A light path of the detection light from the light projector toward the light receiver passes a substrate surrounding member installed around the substrate held by the substrate holding member. The detection light penetrates the substrate surrounding member and has a wavelength which does not penetrate the substrate.