High Temperature Plasma Chuck with Insulating Puck
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in plasma processing is achieving spatially uniform treatment of larger semiconductor wafers with smaller feature sizes, requiring precise temperature control and resistance to corrosive plasma environments, while existing systems face issues with uniformity and material compatibility.
Innovation Solution
A wafer chuck assembly with an electrically insulating puck, conductive shaft, and base, equipped with heater elements and RF/DC voltage capabilities, provides uniform plasma processing by electrostatic clamping and directing reactive ions, using a conductive plate and insulating materials to maintain temperature uniformity and withstand harsh environments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If a conductive chuck is used for plasma processing, then RF power can be applied to generate plasma, but the chuck cannot provide electrostatic clamping
Solution Approach 1:
The chuck is divided into two distinct parts: a conductive base for RF plasma generation and an electrically insulating top surface for electrostatic clamping. This segmentation allows each part to perform its specialized function without interference, resolving the contradiction between plasma generation and clamping capabilities
Solution Approach 2:
An electrically insulating layer is introduced as an intermediary between the conductive base and the workpiece. This insulating layer enables electrostatic clamping on the top surface while allowing RF power to be applied to the conductive base for plasma generation, thus mediating between the two conflicting requirements
2Manufacturing precision
If heater elements are added to the chuck for temperature control, then temperature uniformity can be improved, but the device complexity increases
Solution Approach 1:
The heater elements are integrated directly into the chuck structure, merging the heating function with the existing chuck components. This combination approach provides temperature control capability while minimizing additional complexity compared to separate heating systems
Solution Approach 2:
The chuck is designed to perform multiple functions: electrostatic clamping, RF plasma generation, and temperature control via integrated heaters. This multi-functionality allows a single device to address multiple processing requirements without proportionally increasing complexity
3Manufacturing precision
If the chuck operates at high temperature for better processing, then processing quality improves, but material degradation from corrosive plasma environment worsens
Solution Approach 1:
The chuck utilizes composite material construction with corrosion-resistant materials in the conductive base and electrically insulating materials on the top surface. This composite approach allows the structure to withstand both high temperatures and corrosive plasma environments while maintaining functional performance
Solution Approach 2:
The system operates in a controlled plasma environment that, while corrosive, is managed through proper material selection and design. The inert or controlled atmosphere approach minimizes degradation while allowing high-temperature processing to proceed
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
This solution ensures precise temperature control across the wafer, enhances processing uniformity, and allows for high-temperature operations without thermal or corrosive degradation, effectively addressing the need for improved uniformity and material compatibility in plasma processing.
Implementation Method 1
heating the chuck and the workpiece by passing current through heater elements embedded in the chuck
Implementation Method 2
providing a DC voltage differential across two spatially separated electrodes within the electrically insulating top surface, to clamp the workpiece to the chuck
Implementation Method 3
providing an RF voltage between a conductive plate beneath the chuck, and one or more walls of the chamber, to ignite a plasma from the process gases
Data Source
AI summary
A wafer chuck assembly includes a puck, a shaft and a base. An insulating material defines a top surface of the puck, a heater element is embedded within the insulating material, and a conductive plate lies beneath the insulating material. The shaft includes a housing coupled with the plate, and electrical connectors for the heater elements and the electrodes. A conductive base housing couples with the shaft housing, and the connectors pass through a terminal block within the base housing. A method of plasma processing includes loading a workpiece onto a chuck having an insulating top surface, providing a DC voltage differential across two electrodes within the top surface, heating the chuck by passing current through heater elements, providing process gases in a chamber surrounding the chuck, and providing an RF voltage between a conductive plate beneath the chuck, and one or more walls of the chamber.