Substrate Support Unit Ground Switch for Induction Chucking
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Solution Overview
Problem
The existing substrate treating apparatuses face issues with unintentional chucking of substrates during unloading due to electromagnetic induction, leading to potential damage during the process.
Innovation Solution
A substrate treating apparatus with a support unit that includes an electrode layer, a ground line with multiple parallel lines and resistance elements, and a switch controlled by a controller to manage high-frequency power application, ensuring disconnection during plasma generation and connection during power off to prevent electrostatic chucking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the electrode layer is continuously connected to ground, then the substrate can be reliably chucked during plasma processing, but the substrate may be unintentionally chucked during unloading due to electromagnetic induction
Solution Approach 1:
The ground connection of the electrode layer is made dynamic through a switch that can change its state between connected and disconnected. During plasma processing, the switch connects the electrode layer to ground for reliable substrate chucking. During unloading, the switch disconnects the ground connection to prevent electromagnetic induction from causing unintentional chucking and substrate damage.
Solution Approach 2:
The ground connection to the electrode layer is applied periodically rather than continuously. The controller activates the ground connection only during plasma processing when substrate chucking is needed, and deactivates it during unloading when electromagnetic induction could cause harm. This periodic application of grounding resolves the contradiction between needing reliable chucking and avoiding unintentional damage.
2Productivity
If high-frequency power is continuously applied to the electrode layer, then plasma generation is maintained, but electromagnetic induction causes unintentional substrate chucking during power-off periods
Solution Approach 1:
The ground connection state is dynamically controlled based on plasma processing status. During high-frequency power application, the electrode layer is grounded to enable substrate chucking. When power is turned off during unloading, the ground connection is disconnected to prevent electromagnetic induction from causing substrate damage, thus resolving the contradiction between maintaining productivity and preventing harm.
Solution Approach 2:
The controller monitors the plasma processing state and adjusts the ground connection accordingly. When plasma processing is active, the controller maintains ground connection for substrate chucking. When unloading is detected or power is turned off, the controller disconnects the ground connection to prevent unintentional chucking, creating a feedback-controlled system that balances productivity and substrate safety.
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
Prevents unintentional substrate chucking during unloading, thereby preventing damage by controlling the electrostatic forces effectively.
Implementation Method 1
Charges on the outer wall of the cooling path 4 cause electromagnetic induction phenomena to occur on the electric charges existing in the electrode layer and the plates 1, 2, 3
Implementation Method 2
high-frequency power is applied to the process chamber to excite the process gas into a plasma state
Data Source
AI summary
An embodiment includes a support unit, substrate treating apparatus and substrate treating method. The substrate treating apparatus comprises: a process chamber having a treatment space inside thereof; a support unit for supporting a substrate inside of the process chamber; and a gas supply unit for supplying the treatment gas into the treatment space, wherein the support unit comprises: an electrode layer of a metal material to which a high frequency electric power can be applied; a ground line having one end connected to the electrode layer and the other end grounded; and a switch provided on the ground line.