Proximity Head Resistor Units for Uniform Meniscus Fluid Flow

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current wafer wet clean processes face challenges in maintaining uniform fluid flow relative to a proximity head, leading to contamination from dried fluid droplets, especially as wafer diameters increase, affecting the efficiency and effectiveness of cleaning and drying operations.

Innovation Solution

A proximity head is configured as a one-piece block with a main fluid transfer bore and resistor units to impose resistance, ensuring uniform fluid flow rates across the wafer surface through a network of bores and plenums, maintaining head rigidity and stability even with larger wafer diameters.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If the proximity head is extended to enable cleaning of larger diameter wafers, then the cleaning capability for larger wafers is improved, but the head rigidity deteriorates

Engineering Contradiction:

Improvewafer cleaning areaVSAvoidhead rigidity

Core Design Contradiction:

Area of stationary objectVSStrength

Solution Approach 1:

The proximity head is divided into multiple separate components (body, cap, resistor units) that can be independently manufactured and assembled. This segmentation allows each component to be optimized for its specific function while maintaining overall rigidity through precise mating surfaces and fastening mechanisms.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The proximity head utilizes composite construction combining different materials with complementary properties - the body and cap provide structural rigidity while resistor units integrated into the design provide flow resistance. This composite approach enables the head to maintain rigidity across larger dimensions.

Inventive Principle:

Principle #40Composite materials

2Productivity

If conventional drying techniques are used, then drying of the wafer surface is achieved, but droplet formation occurs leading to contamination

Engineering Contradiction:

Improvedrying efficiencyVSAvoiddroplet contamination

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The harmful droplet formation process is eliminated by replacing conventional drying techniques with a meniscus-based approach. The proximity head extracts fluid from the wafer surface through controlled flow paths and resistor units, preventing droplet formation entirely while achieving effective drying.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent converts the potential harm of fluid evaporation (which causes droplet formation and contamination) into a beneficial controlled flow process. By using resistor units to regulate fluid flow through the meniscus, the system achieves uniform drying without the harmful effects of uncontrolled evaporation.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Productivity

If fluid flow is increased to improve cleaning effectiveness, then cleaning performance is improved, but uniformity of fluid flow deteriorates

Engineering Contradiction:

Improvecleaning effectivenessVSAvoidfluid flow uniformity

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

Resistor units are strategically positioned at specific locations within the proximity head to create localized flow resistance. This local modification of flow characteristics ensures uniform fluid distribution across the entire wafer surface, preventing both excessive and insufficient flow areas while maintaining high cleaning effectiveness.

Inventive Principle:

Principle #3Local quality

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 ensures substantially uniform fluid flow rates across the wafer surface, reducing contamination from dried droplets and enhancing the efficiency of cleaning and drying processes, particularly for larger wafers, by maintaining head rigidity and stability.

Implementation Method 1

resistor units to impose resistance, ensuring uniform fluid flow rates across the wafer surface

Methodology Applied

Scientific EffectFlow resistance: Pressure Drop

Data Source

PatentUS8317966B2Apparatus for substantially uniform fluid flow rates relative to a proximity head in processing of a wafer surface by a meniscus

Publication Date: 2012.11.27 LAM RES CORP

AI summary

Conditioning fluid flow into a proximity head is provided for fluid delivery to a wafer surface. An upper plenum connected to a plurality of down flow bores is supplied by a main bore. The down flow bores provide fluid into the upper plenum, and a resistor bore is connected to the upper plenum. The resistor bore receives a resistor having a shape so as to limit flow of the fluid through the resistor bore. A lower plenum connected to the resistor bore is configured to receive fluid from the resistor bore as limited by the resistor for flow to a plurality of outlet ports extending between the lower plenum and surfaces of the head surface. Fluid flowing through the upper plenum, the resistor bore with the resistor and the lower plenum is substantially conditioned to define a substantially uniform fluid outflow from the plurality of outlet ports, across the width of the proximity head.