Optical Roller Sensing in Substrate Cleaning Under Mist Exposure
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Solution Overview
Problem
Conventional optical sensors used to detect the rotation of driven rollers in substrate cleaning devices are prone to erroneous detection due to liquid scattering or mist formation, leading to hunting or erroneous rotation speed detection, which can cause device process stops and reduced utilization.
Innovation Solution
A substrate cleaning device with a rotation detection part that includes an optical sensor protected by a liquid-filled optical path space, isolated from external interference, and a liquid supply system to maintain consistent detection conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If an optical sensor is used to detect the rotation of the driven roller, then the rotation state can be detected, but liquid droplets or mist may adhere to the optical path and cause erroneous detection
Solution Approach 1:
A liquid-filled enclosure acts as an intermediary barrier between the cleaning liquid environment and the optical sensor. The enclosure is filled with cleaning liquid that creates a liquid seal at the interface, preventing external liquid droplets and mist from reaching the optical sensor while allowing the optical detection function to operate reliably
Solution Approach 2:
The optical sensor is placed within a sealed enclosure filled with cleaning liquid, creating a controlled liquid environment that isolates the sensor from harmful external liquid aerosols and mist. This inert liquid atmosphere protects the optical path from contamination while maintaining detection functionality
2Productivity
If the optical sensor is exposed to the cleaning environment, then it can detect rotation, but the device process may stop due to erroneous signals
Solution Approach 1:
The liquid-filled enclosure serves as a protective intermediary that allows the optical sensor to operate reliably within the cleaning environment without being affected by liquid aerosols and mist, thereby preventing erroneous detection signals that would cause process stoppages and maintaining continuous productivity
3Measurement precision
If liquid is supplied to fill the optical path space, then detection accuracy is maintained, but the system complexity increases
Solution Approach 1:
The cleaning liquid supplied to the substrate cleaning device serves multiple functions: it cleans the substrate and simultaneously fills the optical path enclosure to maintain accurate optical detection. This multi-functionality reduces system complexity by eliminating the need for separate liquids or systems for cleaning and optical path maintenance
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
The solution effectively suppresses erroneous rotation detection by the optical sensor, ensuring accurate substrate rotation detection and preventing device process interruptions.
Implementation Method 1
an optical sensor for detecting rotation of the detected part by irradiation with detection light
Implementation Method 2
light may be reflected on the surface of the adhered droplet or refracted when the light is transmitted through the droplet
Data Source
AI summary
The disclosure provides a substrate cleaning device and a substrate processing device capable of suppressing erroneous rotation detection of an optical sensor due to adhesion of droplets or mist. A substrate cleaning device includes a substrate cleaning part for cleaning a substrate, a drive roller for rotating the substrate, a driven roller rotated by the substrate, and a rotation detection part for detecting rotation of the driven roller. The rotation detection part includes a detected part provided on the driven roller, an optical sensor for detecting rotation of the detected part by irradiation with detection light, and a liquid filling part for filling an optical path forming space in which an optical path of the detection light is formed with a liquid having transmittance.