Substrate Pressure Monitoring for Rapid Depressurization Stability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional substrate processing systems face challenges in maintaining substrate stability during depressurization due to rapid pressure differentials, leading to potential substrate movement and 'popping' or shifting, which limits processing pressures and throughput.

Innovation Solution

A pressure control system that maintains a controlled pressure differential between the frontside and backside of the substrate by regulating the evacuation valve based on real-time pressure readings, ensuring the frontside pressure remains above the backside pressure, allowing for rapid depressurization without substrate movement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If rapid depressurization is performed to increase processing throughput, then processing speed is improved, but substrate movement and popping occur due to uncontrolled pressure differentials

Engineering Contradiction:

Improveprocessing throughputVSAvoidsubstrate stability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The system dynamically changes pressure parameters by independently controlling frontside and backside pressures. The controller adjusts the evacuation valve to maintain a controlled pressure differential, ensuring frontside pressure remains above backside pressure during depressurization, thereby preventing substrate movement while enabling rapid pressure changes for improved throughput

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The system applies different pressure conditions to different sides of the substrate simultaneously. By creating a controlled pressure gradient with higher pressure on the frontside compared to the backside, the system achieves localized pressure control that stabilizes the substrate while allowing overall rapid depressurization

Inventive Principle:

Principle #3Local quality

2Reliability

If high processing pressures are used to prevent substrate movement, then substrate stability is improved, but processing throughput decreases due to slower depressurization rates

Engineering Contradiction:

Improvesubstrate stabilityVSAvoidprocessing throughput

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The system transitions from static high-pressure maintenance to dynamic pressure control. The controller continuously adjusts the evacuation valve based on real-time pressure feedback from sensors, enabling the system to rapidly change pressure conditions while maintaining substrate stability through controlled pressure differentials rather than uniformly high pressure

Inventive Principle:

Principle #15Dynamics

3Speed

If the evacuation valve is fully opened for rapid depressurization, then depressurization speed is improved, but uncontrolled pressure differentials cause substrate popping

Engineering Contradiction:

Improvedepressurization rateVSAvoidsubstrate stability

Core Design Contradiction:

SpeedVSReliability

Solution Approach 1:

The system implements closed-loop feedback control using pressure sensors on both the frontside and backside of the substrate. The controller receives real-time pressure data and continuously adjusts the evacuation valve opening to maintain the desired pressure differential relationship (frontside pressure > backside pressure), enabling rapid depressurization while preventing substrate instability

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system prepares the pressure environment in advance by controlling the backside pressure to be lower than the frontside pressure before and during the depressurization process. This preliminary pressure configuration prevents substrate popping by ensuring the pressure differential always favors substrate stability, even during rapid pressure changes

Inventive Principle:

Principle #10Preliminary action

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

Enables efficient and rapid depressurization of the processing chamber while preventing substrate movement, increasing processing throughput and reducing the risk of substrate displacement during lift-off.

Implementation Method 1

maintains a controlled pressure differential between the frontside and backside of the substrate by regulating the evacuation valve based on real-time pressure readings, ensuring the frontside pressure remains above the backside pressure

Methodology Applied

Scientific EffectPressure differential: Pressure Gradient

Data Source

PatentUS12538747B2Frontside and backside pressure monitoring for substrate movement prevention

Publication Date: 2026.01.27 LAM RES CORP

AI summary

A pressure control system includes a first sensor, a second sensor, an evacuation valve and a controller. The first sensor is configured to detect a frontside pressure within a processing chamber. The frontside pressure is indicative of a downforce on a substrate disposed on a substrate support within the processing chamber. The second sensor is configured to detect a backside pressure on a backside of the substrate. The controller is configured to: control the evacuation valve to remove gas from and reduce the frontside pressure of the processing chamber; and during the removal of gas from a reduction in the frontside pressure of the processing chamber and based on the frontside pressure and the backside pressure, regulate an opening of the evacuation valve such that the frontside pressure does not drop below the backside pressure.