Processing Liquid Supply Monitoring for Bubble-Affected Flowmeters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional substrate processing apparatuses fail to detect abnormality in processing liquid supply due to bubbles adhering to flowmeters, leading to inaccurate flow rate feedback control.
Innovation Solution
Incorporation of a pressure gauge and flowmeter downstream of the pump in the processing liquid supply path, with a controller detecting abnormality based on their measurement values to maintain accurate flow rate control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a flowmeter is used for flow rate feedback control, then flow rate control accuracy is improved, but measurement reliability deteriorates due to bubbles adhering to the flowmeter
Solution Approach 1:
The patent introduces a pressure gauge as an intermediary measurement device to detect supply abnormalities. Instead of relying solely on the flowmeter that is directly affected by bubbles, the pressure gauge measures pressure downstream to indirectly detect flow disruptions caused by bubble adhesion or other blockages, thereby maintaining measurement reliability without sacrificing flow rate control accuracy
Solution Approach 2:
The patent implements a dual-parameter feedback system that monitors both flow rate (via flowmeter) and pressure (via pressure gauge) downstream of the pump. By comparing both measurement values, the controller can distinguish between actual flow changes and measurement errors caused by bubble adhesion, enabling more reliable flow rate feedback control
2Reliability
If measurement devices are installed to detect supply abnormalities, then system reliability is improved, but device complexity increases
Solution Approach 1:
The pressure gauge serves multiple functions: it monitors supply pressure, detects flow abnormalities indirectly through pressure changes, and provides backup measurement when the flowmeter is compromised by bubbles. This multi-functionality improves reliability without requiring additional specialized devices for each function
Solution Approach 2:
The pressure gauge acts as an intermediary detection device that provides indirect information about flow supply status. Rather than installing multiple flowmeters or complex flow detection systems, the pressure gauge mediates the detection process by translating pressure changes into supply status information, simplifying the overall measurement system
Data Source
AI summary
A processing liquid supply system includes a processing liquid supply path, a pump, a pressure gauge and a flowmeter, and a controller. Through the processing liquid supply path, a processing liquid is supplied to a substrate processing device configured to process a substrate. The pump is provided in the processing liquid supply path. The pressure gauge and the flowmeter are provided downstream of the pump in the processing liquid supply path. The controller controls individual components. The controller detects abnormality in supply of the processing liquid based on a measurement value of the pressure gauge and a measurement value of the flowmeter.