Laser Wafer Placement Teaching for Oversized Electrostatic Chucks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for wafer placement on electrostatic chucks are inadequate when the wafer has a larger area than the chuck, making precise positioning difficult.
Innovation Solution
An apparatus and method using laser distance sensors to measure and adjust the relative positions of the wafer and electrostatic chuck, ensuring accurate placement even when the wafer is larger, involving a controller and robot for precise alignment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If traditional light receiving area methods are used on the electrostatic chuck, then wafer position teaching is accurate when the chuck is larger than the wafer, but the method becomes difficult to apply when the wafer is larger than the electrostatic chuck
Solution Approach 1:
The patent introduces a laser distance sensor as an intermediary measurement tool that bridges the gap between the electrostatic chuck and the wafer. Instead of relying on the chuck's light receiving area, the laser sensor measures distances to both the chuck edge and wafer edge, enabling position calculation through mathematical relationships. This intermediary measurement system allows accurate teaching regardless of whether the wafer is smaller or larger than the chuck.
2Adaptability or versatility
If the electrostatic chuck has a larger area than the wafer, then traditional teaching methods work well, but these methods fail when the wafer area exceeds the chuck area
Solution Approach 1:
The laser distance sensor system performs multiple functions: it measures distances to determine both the chuck's position and the wafer's position, calculates relative positions, and enables teaching operations. This universal measurement approach works regardless of the size relationship between wafer and chuck, making the system reliable across all configuration scenarios.
3Manufacturing precision
If laser distance sensors are used to measure positions, then accurate wafer positioning is achieved even when wafer is larger than chuck, but additional measurement and calculation steps are required
Solution Approach 1:
The patent replaces traditional mechanical or optical teaching systems with a laser distance sensor-based measurement system. The laser sensor optically measures distances without physical contact, and the controller automatically calculates positions using these measurements. This substitution eliminates the need for physical teaching tools or complex mechanical alignment mechanisms, achieving high precision with a relatively simple system.
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 accurate wafer positioning by determining and correcting the relative positions of the wafer and electrostatic chuck, ensuring concentric alignment and precise placement.
Implementation Method 1
a laser distance sensor disposed above the electrostatic chuck
Data Source
AI summary
Proposed are a wafer position detection apparatus and a wafer position detection and correction method using the same. More specifically, proposed is an apparatus for wafer placement teaching for adjusting a position of a wafer disposed on an electrostatic chuck, the apparatus including a laser distance sensor disposed above the electrostatic chuck, and a controller configured to control a robot configured to transfer the wafer. The controller checks a relative position of the electrostatic chuck and the wafer disposed on the electrostatic chuck using the laser distance sensor so that the wafer is transferred to a predetermined position, and teaches the position of the wafer using the checked relative position of the electrostatic chuck and the wafer.