Integrated Vacuum Pump System Preventing Gas Condensation

Solution Overview

Problem

Conventional exhausting systems in semiconductor manufacturing face issues with gas condensation and early overheat in vacuum pumps, leading to reduced performance and restricted operable conditions, without a cost-effective solution.

Innovation Solution

The proposed exhausting system sets the environment inside the connecting portion between two vacuum pumps to be within the vapor phase region below the vapor pressure curve of the condensable gas, achieved by positioning the second vacuum pump near the first vacuum pump, thereby preventing gas condensation and reducing the risk of early overheat without increasing system costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If the second vacuum pump is positioned far from the first vacuum pump, then vibrations from the positive displacement pump are reduced, but gas condensation occurs in the connecting portion and early overheat occurs in the turbomolecular pump

Engineering Contradiction:

ImprovevibrationVSAvoidgas condensation prevention

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent merges the first vacuum pump (turbomolecular pump) and the second vacuum pump (positive displacement pump) into a single integrated unit. This integration eliminates the connecting portion between separate pumps, preventing gas condensation while keeping the pumps close together to maintain low pressure in the connecting portion. The integrated design allows the pumps to work together as a unified system, resolving the contradiction between proximity (for pressure control) and separation (for vibration reduction).

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent introduces a vibration isolation mechanism as an intermediary between the first and second vacuum pumps. This intermediary component allows the pumps to be positioned close together (maintaining low pressure and preventing condensation) while simultaneously isolating the turbomolecular pump from vibrations generated by the positive displacement pump. The vibration isolation mechanism acts as a mediator that decouples the harmful mechanical vibrations while maintaining the beneficial spatial proximity.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the second vacuum pump is positioned near the first vacuum pump, then gas condensation is prevented, but vibrations from the positive displacement pump affect the turbomolecular pump

Engineering Contradiction:

Improvegas condensation preventionVSAvoidvibration

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent merges the first vacuum pump (turbomolecular pump) and the second vacuum pump (positive displacement pump) into a single integrated unit. This integration eliminates the connecting portion between separate pumps, preventing gas condensation while keeping the pumps close together to maintain low pressure in the connecting portion. The integrated design allows the pumps to work together as a unified system, resolving the contradiction between proximity (for pressure control) and separation (for vibration reduction).

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent introduces a vibration isolation mechanism as an intermediary between the first and second vacuum pumps. This intermediary component allows the pumps to be positioned close together (maintaining low pressure and preventing condensation) while simultaneously isolating the turbomolecular pump from vibrations generated by the positive displacement pump. The vibration isolation mechanism acts as a mediator that decouples the harmful mechanical vibrations while maintaining the beneficial spatial proximity.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If conventional measures are taken to prevent gas condensation (heating the connecting portion), then gas condensation is prevented, but early overheat occurs in the turbomolecular pump due to increased temperature

Engineering Contradiction:

Improvegas condensation preventionVSAvoidturbomolecular pump temperature

Core Design Contradiction:

ReliabilityVSTemperature

Solution Approach 1:

The patent extracts and eliminates the heater component from the system. Instead of using conventional heating methods to prevent gas condensation, the invention removes the need for heating by integrating the pumps and maintaining low pressure in the connecting portion. This extraction approach prevents gas condensation through pressure control rather than temperature increase, thereby avoiding early overheat in the turbomolecular pump while still preventing condensation.

Inventive Principle:

Principle #2Taking out (Extraction)

4Loss of energy

If thick pipe laying is used to connect the vacuum pumps, then pipe laying loss is reduced, but system cost increases

Engineering Contradiction:

Improvepipe laying lossVSAvoidsystem cost

Core Design Contradiction:

Loss of energyVSEase of manufacture

Solution Approach 1:

The patent merges the first vacuum pump and the second vacuum pump into a single integrated unit, eliminating the need for separate pipe laying connections. This integration removes the pipe laying loss issue entirely by creating a direct internal connection between the pumps, while avoiding the increased system cost associated with using thick pipe laying. The integrated design achieves low resistance connection without requiring expensive thick piping.

Inventive Principle:

Principle #5Merging (Combining)

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 configuration effectively prevents gas condensation and early overheat in the vacuum pumps, allowing for relaxed operable conditions such as increased gas flow rates, while reducing system costs and energy consumption.

Implementation Method 1

an environment inside the connecting portion is set to be an environment included in a vapor phase region below a vapor pressure curve of the condensable gas flowing through an inside of the connecting portion

Methodology Applied

Scientific EffectVapor pressure curve: Vapour Pressure

Data Source

PatentUS12276283B2Integrated connector between first and second vacuum pumps creating a vapor phase region environment

Publication Date: 2025.04.15 EDWARDS JAPAN

AI summary

An exhausting system capable of preventing gas condensation and early overheat in a vacuum pump without causing an increase in the costs of the entire exhausting system and suitable for relaxing the operable conditions of the entire exhausting system including a flow rate at which gas is successively exhausted. An exhausting system is predicated on a constitution including: at least a first vacuum pump and a second vacuum pump connected in series; and a connecting portion disposed therebetween, the exhausting system exhausting gas containing a condensable gas via the vacuum pumps and the connecting portion. In the exhausting system, an environment inside the connecting portion is set to an environment having a vapor phase region below a vapor pressure curve of the condensable gas flowing through an inside of the connecting portion by providing the second vacuum pump near the first vacuum pump.