Image Processing and Deep Learning-based Defect Detection Theory for Sapphire Epi-Wafer in Green LED Manufacturing

  • Suk Ju Ko (Department of Electronics Engineering, Myongji University) ;
  • Ji Woo Kim (Department of Electronics Engineering, Myongji University) ;
  • Ji Su Woo (Department of Industrial and Management Engineering, Myongji University) ;
  • Sang Jeen Hong (Department of Semiconductor Engineering, Myongji University ) ;
  • Garam Kim (Department of Electronics Engineering, Myongji University)
  • Received : 2023.06.02
  • Accepted : 2023.06.21
  • Published : 2023.06.30

Abstract

Recently, there has been an increased demand for light-emitting diode (LED) due to the growing emphasis on environmental protection. However, the use of GaN-based sapphire in LED manufacturing leads to the generation of defects, such as dislocations caused by lattice mismatch, which ultimately reduces the luminous efficiency of LEDs. Moreover, most inspections for LED semiconductors focus on evaluating the luminous efficiency after packaging. To address these challenges, this paper aims to detect defects at the wafer stage, which could potentially improve the manufacturing process and reduce costs. To achieve this, image processing and deep learning-based defect detection techniques for Sapphire Epi-Wafer used in Green LED manufacturing were developed and compared. Through performance evaluation of each algorithm, it was found that the deep learning approach outperformed the image processing approach in terms of detection accuracy and efficiency.

Keywords

Acknowledgement

This study was conducted with the support through the Korea Institute for Advancement of Technology (G02P1880 0005501). We would like to express our gratitude to Nexus1 for the providing research topic, mentoring, and assistance.

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