Focus Ring Conductive Member to Reduce Plasma Cleaning Downtime
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional plasma processing apparatuses require frequent offline cleaning due to particulate accumulation on the focus ring, which reduces its usable life and disrupts production throughput.
Innovation Solution
Incorporating a conductive member between the focus ring and insulators to reduce particulate accumulation, positioned strategically to minimize interference with the electrostatic chuck while allowing for extended operation without cleaning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a focus ring is used in a plasma processing apparatus, then plasma uniformity and control are improved, but particulate accumulates on the focus ring requiring frequent cleaning
Solution Approach 1:
A conductive member is introduced as an intermediary component between the focus ring and the insulator. This conductive member acts as a mediator that redirects ion bombardment away from the focus ring surface, thereby reducing particulate accumulation while preserving the focus ring's plasma control functions
Solution Approach 2:
The patent converts the harmful effect of ion bombardment (which causes particulate accumulation) into a beneficial effect by directing it toward the conductive member instead. The conductive member absorbs the harmful ion flux, transforming it into a protective mechanism that actually reduces cleaning requirements
2Manufacturing precision
If the focus ring is cleaned frequently to remove particulate, then processing quality is maintained, but operational efficiency and throughput decrease
Solution Approach 1:
The harmful ion bombardment that causes particulate accumulation is redirected onto the conductive member, converting a harmful effect into a protective mechanism. This reduces particulate buildup on the focus ring, maintaining processing quality while minimizing cleaning frequency and maximizing throughput
3Loss of time
If a conductive member is added between the focus ring and insulator, then particulate accumulation is reduced, but device complexity increases
Solution Approach 1:
The pedestal assembly is segmented into distinct functional zones: the focus ring for plasma control, the conductive member for ion bombardment management, and the insulator for electrical isolation. This segmentation allows each component to perform its specific function efficiently, reducing overall system complexity through functional decomposition
Solution Approach 2:
The conductive member serves multiple functions: it provides a surface for ion bombardment, electrically connects the focus ring to ground, and prevents particulate accumulation. This multi-functionality reduces the need for additional components, thereby limiting the increase in device complexity
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 conductive member effectively reduces particulate accumulation, enabling longer operation times and increased throughput by minimizing the need for focus ring cleaning.
Implementation Method 1
particulate can build up on the focus ring due, at least in part, to a bias voltage being applied across the workpiece via the electrostatic chuck
Implementation Method 2
an electrostatic chuck configured to support a workpiece
Data Source
AI summary
A pedestal assembly is provided. The pedestal assembly includes an electrostatic chuck configured to support a workpiece. The pedestal assembly includes a focus ring have a top surface and a bottom surface. The focus ring can be configured to surround a periphery of the workpiece when the workpiece is positioned on the electrostatic chuck. The pedestal assembly includes a plurality of insulators. The pedestal assembly further includes a conductive member positioned between at least a portion of the bottom surface of the focus ring and at least a portion of one of the plurality of insulators.