Bladder-Based Dispense Unit for Semiconductor Fluid Delivery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor fabrication, existing fluid delivery systems face challenges in maintaining high-purity and high-flow rate dispensing of chemicals onto substrates while minimizing defects caused by impurities, gas bubbles, and particle generation, due to the need for fine filters which reduce flow rates and increase the risk of defects from gas dissolution and particle aggregation.
Innovation Solution
A bladder-based fluid delivery system that uses an elongate bladder with in-direct pressure/volume control to compensate for filter-lag, minimizing gas dissolution and reducing the number of system components, thereby maintaining high-purity and high-flow rate dispensing by expanding to collect and contract fluid, maintaining a linear flow path and reducing cross-flows.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If relatively fine filters are used to filter chemicals immediately prior to dispensing, then chemical purity is improved, but fluid flow rate decreases
Solution Approach 1:
The system performs preliminary filtering of chemicals before they enter the dispense line, rather than filtering immediately prior to dispensing. This allows the use of finer filters without compromising flow rate during actual dispensing operations.
Solution Approach 2:
The filtering function is segmented from the dispensing function. The system uses separate filtering stages upstream from the dispense point, allowing optimization of each function independently - fine filtering for purity and unrestricted flow for dispensing.
2Reliability
If pre-filtered chemistry is purchased for use in coater/developer tool, then defect avoidance is improved, but cost increases and defects can still develop during transport or use
Solution Approach 1:
The system provides self-service filtering capability, allowing the fabrication tool to filter chemicals on-demand at the point of use. This eliminates reliance on external pre-filtered chemistry suppliers and ensures consistent filtering performance.
Solution Approach 2:
The system introduces an intermediary filtering stage between the chemical storage and the dispense point. This intermediary filter captures particles that may have developed during transport or storage, preventing them from reaching the substrate.
3Manufacturing precision
If filters are made finer to meet purity requirements, then chemical purity is improved, but the rate of fluid flow decreases making it difficult to meet dispense flow requirements
Solution Approach 1:
The system performs preliminary filtering upstream in the chemical delivery system where slower flow rates are acceptable. This allows fine filters to be used without impacting the flow rate during actual dispensing operations.
Solution Approach 2:
The system adds a temporal dimension to the filtering process by separating when filtering occurs from when dispensing occurs. Filtering happens in advance during chemical delivery, while dispensing happens on-demand with already-filtered chemicals.
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 system effectively reduces defectivity by minimizing gas dissolution and particle generation, ensuring high-purity and high-precision dispensing while maintaining the required flow rates, thus improving the quality of deposited films.
Implementation Method 1
The chamber is configured to contain hydraulic fluid in contact with an exterior surface of the elongate bladder. The hydraulic fluid housing includes a displacement chamber in fluid connection with the chamber containing the elongate bladder.
Implementation Method 2
The elongate bladder is configured to laterally expand and laterally contract within the chamber such that when the elongate bladder contains process fluid, a volume of the process fluid within the elongate bladder is increasable and reducible.
Implementation Method 3
The displacement chamber includes a displacement member that is insertable into the displacement chamber and retractable from the displacement chamber. The controller is configured to activate a volume-control system that selectively decreases hydraulic fluid pressure on the elongate bladder by retracting a portion of the displacement member from the displacement chamber
Data Source
AI summary
Techniques herein include a bladder-based dispense system using an elongate bladder configured to selectively expand and contract to assist with dispense actions. This dispense system compensates for filter-lag, which often accompanies fluid filtering for microfabrication. This dispense system also provides a high-purity and high precision dispense unit. A modular hydraulic unit houses the elongate bladder and hydraulic fluid in contact with an exterior surface of the bladder. When pressurized process fluid is in the elongate bladder, hydraulic controls can selectively reduce pressure on the bladder to cause expansion, and then selectively increase hydraulic pressure to assist with a dispense action.