Wafer Die Positioning via Iterative Optical Alignment

The patent replaces the mechanical pre-alignment system with an optical positioning system. A camera captures images of the wafer, and image processing algorithms calculate the rotation angle and position of each die. This substitution of mechanical systems with optical and computational methods achieves high positioning accuracy (within 1 micrometer) without requiring complex mechanical adjustment mechanisms.

The patent creates a digital copy of the wafer by capturing an image with a camera. The image processing system then analyzes this digital copy to determine the position and orientation of each die. This copying approach allows for precise measurement and calculation without physically touching or disturbing the wafer, achieving high accuracy while keeping the physical system simple.

The patent performs preliminary action by capturing the wafer image and calculating the rotation angle and die positions before the actual processing begins. The system pre-processes the positioning information through image capture and algorithmic calculation, so that when processing starts, the wafer is already accurately positioned. This preliminary computational work eliminates the need for time-consuming mechanical adjustments during the processing phase.

The patent replaces time-consuming mechanical adjustment operations with rapid optical capture and computational analysis. The camera captures the wafer image instantly, and the image processing algorithm quickly calculates the positioning parameters. This mechanical-to-optical-computational substitution dramatically reduces the time required for positioning while achieving high accuracy.

The patent maintains continuity of useful action by performing all image captures and calculations in a continuous automated sequence without interruption. The camera captures images, the system continuously processes the images to calculate rotation angles and die positions, and the wafer is rotated accordingly. This continuous automated workflow eliminates idle time and manual intervention, ensuring that the multiple measurement and rotation operations do not significantly impact overall productivity.

The system performs self-service by automatically capturing images, calculating positioning parameters, and controlling wafer rotation without requiring external intervention. The image processing algorithm autonomously determines the rotation angle and die positions from the captured images, and the system automatically executes the positioning operations. This self-service capability streamlines the process and maintains high productivity despite the multiple operational steps involved.