Bypass Flow Path Concentration Sensor for Substrate Liquid Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional substrate liquid processing apparatuses face issues with concentration sensor failure or malfunction due to erosion or impurity adherence, leading to unsatisfactory substrate processing, as the concentration sensor is often in direct contact with the processing liquid and can precipitate dusts into the liquid.
Innovation Solution
A substrate liquid processing apparatus with a concentration sensor placed in a bypass flow path within the processing liquid discharge unit, allowing intermittent or continuous discharge of processing liquid for measurement, reducing sensor contact time and preventing impurity adherence, while maintaining accurate silicon concentration monitoring.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the concentration sensor is placed in direct contact with the processing liquid to measure silicon concentration, then the measurement function is achieved, but the sensor suffers from erosion and impurity adherence leading to failure or malfunction
Solution Approach 1:
The flow path is segmented into a main flow path for processing liquid circulation and a bypass flow path for sensor measurement. The concentration sensor is placed in the bypass flow path, separating the measurement function from the harsh processing environment while still enabling accurate silicon concentration monitoring through periodic sampling of the processing liquid.
Solution Approach 2:
The bypass flow path acts as an intermediary between the processing liquid and the concentration sensor. This intermediate channel allows the sensor to measure the processing liquid's concentration without direct exposure to the full flow and harsh conditions that cause erosion and impurity accumulation.
2Measurement precision
If the concentration sensor is continuously exposed to processing liquid for real-time monitoring, then the measurement capability is improved, but dust precipitation and impurity adherence increase causing sensor malfunction
Solution Approach 1:
Instead of continuous exposure, the system uses periodic action by controlling the circulation pump to intermittently supply processing liquid to the bypass flow path. The concentration sensor measures the silicon concentration during these periodic intervals, reducing cumulative exposure to harmful factors while maintaining effective monitoring capability.
Data Source
AI summary
Disclosed is a substrate liquid processing apparatus including a processing liquid storage unit that stores a processing liquid; a processing liquid supply unit that supplies the processing liquid to the processing liquid storage unit; a processing liquid circulation unit that circulates the processing liquid inside the processing liquid storage unit; a processing liquid discharge unit that discharges the processing liquid; a concentration sensor that measures a concentration in the processing liquid; and a controller that controls the processing liquid supply unit. The controller controls the processing liquid circulation unit to circulate the processing liquid, the processing liquid discharge unit to discharge the circulated processing liquid intermittently at a predetermined timing or continuously for a predetermined period of time, the processing liquid supply unit to newly supply the processing liquid, and the concentration sensor to measure the concentration in the processing liquid at a predetermined timing.