Supercritical Drying Apparatus for High-Aspect-Ratio Pattern Collapse
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor device manufacturing, miniaturized patterns on substrates are prone to collapse during drying processes due to surface tension, and existing drying methods are inadequate in preventing this collapse.
Innovation Solution
A substrate processing apparatus utilizing a supercritical drying technique with a processing vessel, substrate holder, fluid supply device, and controller to manage the supply of processing fluid in a supercritical state and gas state, ensuring controlled drying that minimizes pattern disturbance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional drying method is used to remove liquid from the substrate, then the drying process can be completed, but the pattern on the substrate collapses due to surface tension
Solution Approach 1:
The patent changes the physical parameters of the drying environment by using supercritical carbon dioxide (high pressure and temperature) to eliminate surface tension effects that cause pattern collapse during conventional drying
Solution Approach 2:
The patent utilizes the phase transition of carbon dioxide between supercritical state and gaseous state to achieve drying without surface tension, where the supercritical fluid penetrates and replaces the liquid, then transitions to gas for gentle evaporation
2Ease of operation
If the cover body is opened to supply gas state fluid for purging, then the processing vessel can be prepared, but the opening state exposes the substrate to unnecessary conditions
Solution Approach 1:
The patent implements dynamic control of the cover body, transitioning it between closed and open states based on the processing phase, ensuring the substrate is only exposed to gas state fluid when necessary for purging while maintaining stability during supercritical processing
3Productivity
If the substrate is removed from the substrate holder to supply supercritical fluid, then the fluid can be supplied, but the substrate is exposed to inappropriate conditions
Solution Approach 1:
The patent segments the fluid supply system into separate lines (supercritical fluid supply line and gas state fluid supply line) with independent flow control, allowing simultaneous or sequential operation without requiring substrate removal or cover opening
Solution Approach 2:
The patent uses flow control devices as intermediaries to regulate and switch between supercritical and gas state fluid supply, enabling precise control of fluid delivery to the processing vessel without mechanical intervention
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
Effectively prevents pattern collapse by maintaining a laminar flow of supercritical fluid, replacing surface liquids without disturbing the pattern, and ensuring efficient drying of substrates with fine and high-aspect-ratio features.
Implementation Method 1
a liquid being accumulated on a front surface of the substrate, by using a supercritical drying technique
Implementation Method 2
the processing fluid in the supercritical state is supplied to the processing vessel
Implementation Method 3
maintaining a laminar flow of supercritical fluid
Implementation Method 4
a drying method using a processing fluid in a supercritical state is used in a drying process
Implementation Method 5
the fluid in the gas state is supplied to the processing vessel
Implementation Method 6
ensuring controlled drying that minimizes pattern disturbance
Data Source
AI summary
A substrate processing apparatus includes: a processing vessel having an opening; a cover body configured to close the opening; a cover body moving mechanism configured to move the cover body between a closed position and an open position; a substrate holder configured to horizontally hold a substrate; a fluid supply device configured to supply a processing fluid in a supercritical state and a fluid in a gas state to the processing vessel; and a controller configured to control the fluid supply device such that the processing fluid is supplied to the processing vessel in a first state in which the substrate is held by the substrate holder and the cover body is located at the closed position, and such that the fluid is supplied to the processing vessel in a second state in which the cover body is located at the open position.