Dielectric ESC Cover With Cooling Conduits for Plasma Erosion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electrostatic chucks (ESCs) in plasma processing apparatuses face erosion and contamination issues due to exposure to harsh processing conditions, leading to costly replacements and tool downtime, with particulate deposits accumulating on the annular cover and contaminating subsequent processing steps.
Innovation Solution
A substrate support system featuring a dielectric cover with conduits for cooling gas flow over the ESC, which protects the ESC from erosion and contamination by being designed as a consumable part that can be replaced, maintaining effective thermal regulation and clamping while reducing particulate deposit accumulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the ESC is exposed to processing conditions for effective substrate processing, then substrate processing functionality is maintained, but the ESC surface erodes and accumulates particulate deposits over time
Solution Approach 1:
A dielectric cover is introduced as an intermediary component between the ESC and the plasma processing environment. The cover protects the ESC from direct exposure to harmful plasma conditions, ion bombardment, and particulate deposition, while still allowing the ESC to perform its substrate clamping and thermal regulation functions through the cover material.
Solution Approach 2:
The substrate support system is segmented into two distinct functional components: a reusable ESC and a replaceable dielectric cover. This segmentation allows the cover to be replaced periodically when contaminated, protecting the expensive ESC from damage and extending its operational lifetime.
2Reliability
If a cover is added to protect the ESC, then erosion and contamination are reduced, but device complexity increases
Solution Approach 1:
The dielectric cover serves multiple functions simultaneously: it protects the ESC from erosion and contamination, provides a surface for substrate placement, allows cooling gas flow through its conduits, and maintains electrical insulation. This multi-functionality reduces the need for additional separate components, thereby limiting the increase in device complexity.
3Temperature
If cooling gas flow is permitted through the cover, then thermal regulation is maintained, but particulate deposits may accumulate in the conduits
Solution Approach 1:
The dielectric cover is designed as a consumable, replaceable component. When particulate deposits accumulate in the conduits or on the cover surface, the entire cover can be replaced with a new one, ensuring continued effective cooling gas flow and thermal regulation without requiring complex cleaning systems or maintenance of the ESC.
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 solution significantly extends the lifetime of the ESC, reduces contamination, and maintains efficient clamping and thermal regulation, with the cover's design allowing for adequate thermal conductivity and clamping force while preventing particulate deposits from accumulating on the ESC.
Implementation Method 1
an electrostatic chuck (ESC) comprising an upper surface... operating the electrostatic chuck to electrostatically clamp the substrate in position
Implementation Method 2
one or more conduits extending through the cover to permit a cooling gas to flow from the second face to the first face... flowing a cooling gas from the first face to the second face via the one or more conduits to cool the substrate
Data Source
AI summary
A substrate support includes an electrostatic chuck having an upper surface, and a cover positioned on the electrostatic chuck to cover the upper surface thereof. The cover includes a first face adjacent the upper surface of the electrostatic chuck, a second face for supporting a substrate, and one or more conduits extending through the cover to permit a cooling gas to flow from the second face to the first face. The cover is made from a dielectric material.