Electrostatic Wafer Conveyance Robot Holding Surface
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wafer conveyance methods in semiconductor manufacturing face challenges in increasing productivity due to reduced positional accuracy at high temperatures and slow transfer speeds, particularly with structures using slip-proof pads and electrostatic chucks.
Innovation Solution
A wafer conveyance method and system utilizing a conveyance robot with an electrostatic chuck mechanism, where a holding surface with an electrode moves to attract and hold wafers quickly, allowing for rapid transfer without compromising positional accuracy by applying voltage to the electrode during the transfer process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If pads are attached on a wafer at high temperature to prevent slipping, then the wafer can be held securely, but the positional accuracy is reduced during transfer
Solution Approach 1:
The patent replaces the mechanical pad attachment system with an electrostatic attraction system. Instead of using physical pads that require thermal activation and cause positional drift, the invention uses electrostatic fields generated by electrodes on the holding surface to securely hold the wafer during transfer, eliminating the need for mechanical friction-based holding while maintaining both security and precision
Solution Approach 2:
The patent changes the physical state and parameters of the holding surface by applying voltages to electrodes, transforming it from a passive mechanical surface to an actively controllable electrostatic field. This allows dynamic adjustment of holding force without mechanical contact, enabling secure wafer holding during transfer while maintaining positional accuracy through controlled field interactions
2Reliability
If electrostatic chucking is used to hold the wafer, then the wafer can be held securely, but a predetermined time is required to attract and release the wafer, reducing transfer speed
Solution Approach 1:
The patent applies preliminary action by pre-positioning the holding surface with activated electrodes near the wafer before actual transfer begins. The electrostatic field is prepared in advance, allowing immediate attraction when transfer starts, eliminating the delay typically required to build up electrostatic charging. This enables rapid wafer acquisition without sacrificing holding security
Solution Approach 2:
The patent implements dynamic control of the electrostatic field through programmable voltage application to multiple electrodes. The system can rapidly adjust field strength and distribution during transfer, allowing quick attraction and release cycles. This dynamic responsiveness enables high-speed transfer while maintaining secure holding during critical transfer phases
3Productivity
If the conveyance robot moves quickly to increase productivity, then wafer transfer speed increases, but positional accuracy may be compromised
Solution Approach 1:
The patent replaces mechanical friction-based holding with electrostatic field-based holding, enabling high-speed transfer without the positional drift that occurs with mechanical pads. The electrostatic field provides continuous, contactless holding force that remains effective even during rapid acceleration and deceleration, decoupling transfer speed from positional accuracy
Solution Approach 2:
The patent implements feedback control through voltage adjustment based on wafer position detection. During high-speed transfer, the system monitors wafer position and dynamically adjusts electrode voltages to maintain optimal holding force and correct any positional deviations in real-time, ensuring high positional accuracy is maintained even at increased transfer speeds
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 approach enables faster and more accurate wafer conveyance between processing chambers, reducing transfer time and maintaining positional precision, as demonstrated by experiments showing minimal displacement and no discharge during transfer.
Implementation Method 1
a holding surface of a conveyance robot having an electrode for electrostatic attraction
Data Source
AI summary
Disclosed are a substrate conveyance method and substrate conveyance system that are able to quickly transfer a substrate without losing positional accuracy. Using an electrostatic chuck mechanism in the holding of a wafer (W) by the holding surface (210) of a conveyance robot, the wafer (W) is transferred from a supporting surface (303) to the holding surface (210) in the state where an electrostatic attraction force is generated at the holding surface (210). As a result, since it is possible to hold the wafer by means of the electrostatic attraction force starting immediately after the wafer (W) has been transferred to the holding surface (210), it is possible to rapidly execute a wafer (W) conveying operation and thus it is possible to reduce the conveying time of the wafer between processing chambers.