Multi-Wafer Processing Chamber Asymmetric Shielding

Solution Overview

Problem

Multi-wafer processing chambers face challenges in achieving uniformity of process results due to cross-talk between adjacent wafer processing stations, leading to variations in pressure and contamination, which are not effectively addressed by existing tandem chamber designs that prioritize independence over feedback control.

Innovation Solution

A processing chamber design with asymmetrically disposed electrically conductive surfaces and a shield arrangement that includes a first annular shield member and a movable second shield member, which provides enhanced uniformity by isolating treatment pressure and minimizing charged species cross-contamination while allowing neutral species to equilibrate between processing stations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If multiple workpiece processing stations are placed in a shared process chamber to enhance throughput, then productivity increases, but process uniformity deteriorates due to cross-talk and contamination between adjacent stations

Engineering Contradiction:

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The shared process chamber is segmented into multiple isolated processing regions by partition walls, allowing each station to be treated as a separate processing environment while maintaining overall system integration and throughput

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Electrostatic shields are introduced as intermediary elements between adjacent processing stations to block charged species cross-contamination while permitting neutral species transport, thereby maintaining process uniformity without sacrificing throughput

Inventive Principle:

Principle #24Intermediary (Mediator)

2Manufacturing precision

If tandem single wafer processing chambers are used with separate processing regions to reduce cross-talk contamination, then process uniformity improves, but device complexity and cost increase

Engineering Contradiction:

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

Multiple processing stations are merged into a single shared chamber environment with selective isolation, combining the benefits of separate processing regions with the cost and simplicity advantages of a unified chamber structure

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

Electrostatic shields serve as intermediary elements that provide charged species blocking without requiring complete physical separation of processing regions, reducing structural complexity compared to fully isolated tandem chambers

Inventive Principle:

Principle #24Intermediary (Mediator)

3Object-affected harmful factors

If electrostatic shields are used to block charged species between processing regions, then contamination is reduced, but neutral species transport and pressure equalization may be affected

Engineering Contradiction:

Core Design Contradiction:

Object-affected harmful factorsVSQuantity of substance

Solution Approach 1:

The electrostatic shields are configured with specific geometric characteristics and positioning that provide charged species blocking in critical directions while maintaining neutral species transport pathways, creating localized protection without compromising overall species flow

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The shields are designed with specific electrical potential parameters and geometric parameters that optimize the balance between charged species blocking and neutral species transport, allowing pressure equalization while maintaining contamination protection

Inventive Principle:

Principle #35Parameter changes

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 achieves improved uniformity of the treatment process across workpieces by isolating treatment pressure and minimizing charged species contamination, resulting in consistent process results and reduced maintenance needs, while maintaining high throughput and cost-effectiveness.

Implementation Method 1

an electrostatic shield arranged in each processing region and having a circuitous configuration which blocks travel of charged species from one processing station to an adjacent processing station while allowing transport of neutral species between the processing stations

Methodology Applied

Scientific EffectElectrostatic shielding: Faraday Cage

Implementation Method 2

Each of the processing stations includes a plasma source or other suitable treatment source such as, for example, an electromagnetic energy source to perform a process

Methodology Applied

Scientific EffectPlasma: Plasma

Data Source

PatentUS9184072B2Advanced multi-workpiece processing chamber

Publication Date: 2015.11.10

AI summary

An apparatus and method are described for processing workpieces in a treatment process. A multi-wafer chamber defines a chamber interior including at least two processing stations within the chamber interior such that the processing stations share the chamber interior. Each processing station includes a plasma source and a workpiece pedestal for exposing one of the workpieces to the treatment process using a respective plasma source. The chamber includes an arrangement of one or more electrically conductive surfaces that are asymmetrically disposed about the workpiece at each processing station in a way which produces a given level of uniformity of the treatment process on a major surface of each workpiece. A shield arrangement provides an enhanced uniformity of exposure of the workpiece to the respective one of the plasma sources that is greater than the given level of uniformity that would be provided in an absence of the shield arrangement.