DLADC: Deep Learning Based Semiconductor Wafer Surface Defects Recognition

In semiconductor manufacturing, surface defects on wafers must be classified accurately for better yield management. To manage the increasing chip demand in speed and scale, automatic defect classification (ADC) system has been introduced. Most existing ADC systems utilize machine learning-based algorithms that require manual feature extractions and manual intervention such as human-based classification for accuracy and consistency. These methods are labour-intensive, unreliable, and highly prone to human error. Therefore, by leveraging on deep learning technologies, this paper proposes DLADC - an ADC system using a deep convolutional neural network (CNN) architecture for detecting and classifying semiconductor wafer surface defects. The proposed system takes Scanning Electron Microscope (SEM) images as input and outputs the defect’s class and location. The proposed system also sub-classifies particle-type defects into various sizing groups. Identification of defect types that occurred on wafer surfaces allows for better defect root cause analysis, and the additional information of defect size further serves as an essential indication of the origin of machine failure. The proposed DLADC promotes 2x time saving while achieving an improved accuracy of 93.69% based on experimental results with a real semiconductor defect dataset. Not only does DLADC outperforms the 70% classification performance of trained operators, but it also surpasses the 90% classification performance of industrially pragmatic defect classification. © 2022. All Rights Reserved.