Substrate Cleaning Device Uplift Force Control

Solution Overview

Problem

The existing substrate cleaning devices are inefficient in cleaning the lower-surface center region of substrates due to displacement caused by weight and applied loads, resulting in reduced contact area and frequency of cleaning.

Innovation Solution

A substrate cleaning device with a cleaning controller that adjusts the uplift force of the cleaner during the cleaning of the lower-surface center region, utilizing a displacement sensor to maintain the substrate within a predetermined displacement range, ensuring effective contact and preventing damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Force

If the brush is pressed against the back-surface center portion of the wafer to clean it, then the cleaning force is improved, but the wafer center portion is displaced upward and the contact area between the brush and wafer is reduced

Engineering Contradiction:

Improvecleaning forceVSAvoidcontact area

Core Design Contradiction:

ForceVSArea of stationary object

Solution Approach 1:

The patent applies dynamics by making the cleaner movable in the vertical direction and dynamically adjusting the uplift force during the cleaning process. The cleaner moves from an initial position where it contacts the wafer center to a final position where it contacts the wafer peripheral portion, with the uplift force being varied continuously throughout this movement to maintain optimal contact area and cleaning effectiveness.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes physical parameters by varying the uplift force applied to the cleaner during the cleaning process. The uplift force is adjusted from an initial value to a final value in a controlled manner, which changes the contact pressure and contact area between the cleaner and the wafer, thereby optimizing cleaning performance across different regions of the wafer.

Inventive Principle:

Principle #35Parameter changes

2Force

If the wafer center portion is displaced upward by the brush load, then the cleaning force is improved, but the lower surface of the wafer becomes curved and the contact area is reduced

Engineering Contradiction:

Improvecleaning forceVSAvoidwafer flatness

Core Design Contradiction:

ForceVSShape

Solution Approach 1:

The patent applies dynamics by making the cleaner movable in the vertical direction and dynamically adjusting the uplift force during the cleaning process. The cleaner moves from an initial position where it contacts the wafer center to a final position where it contacts the wafer peripheral portion, with the uplift force being varied continuously throughout this movement to maintain optimal contact area and cleaning effectiveness.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes physical parameters by varying the uplift force applied to the cleaner during the cleaning process. The uplift force is adjusted from an initial value to a final value in a controlled manner, which changes the contact pressure and contact area between the cleaner and the wafer, thereby optimizing cleaning performance across different regions of the wafer.

Inventive Principle:

Principle #35Parameter changes

3Force

If the contact area between the brush and wafer is reduced due to wafer displacement, then the cleaning force concentration is improved, but the cleaning frequency of the non-contact region is reduced

Engineering Contradiction:

Improvecleaning force concentrationVSAvoidcleaning frequency

Core Design Contradiction:

ForceVSProductivity

Solution Approach 1:

The patent applies dynamics by making the cleaner movable in the vertical direction and dynamically adjusting the uplift force during the cleaning process. The cleaner moves from an initial position where it contacts the wafer center to a final position where it contacts the wafer peripheral portion, with the uplift force being varied continuously throughout this movement to maintain optimal contact area and cleaning effectiveness.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent ensures continuity of useful action by continuously moving the cleaner across different positions on the wafer surface and continuously adjusting the uplift force throughout the cleaning process. This continuous action ensures that all regions of the wafer, including the center and peripheral portions, receive adequate cleaning attention without interruption.

Inventive Principle:

Principle #20Continuity of useful action

Data Source

PatentUS20240390951A1Substrate cleaning device and substrate cleaning method

Publication Date: 2024.11.28 SCREEN HOLDINGS CO LTD

AI summary

A substrate cleaning device includes a pair of upper holding devices that hold an outer peripheral end of a substrate, a lower-surface brush that comes into contact with a lower surface of the substrate to clean the lower surface of the substrate and a control device that changes an uplift force for uplifting the lower-surface brush in a period during which the lower-surface brush cleans a lower-surface center region of the substrate.