This paper introduces a novel wafer-edge quality inspection method based on analysis of curved-edge diffractive fringe patterns, which occur when light is incident and diffracts around the wafer edge. The proposed method aims to identify various defect modes at the wafer edges, including particles, chipping, scratches, thin-film deposition, and hybrid defect cases. The diffraction patterns formed behind the wafer edge are influenced by various factors, including the edge geometry, topography, and the presence of defects. In this study, edge diffractive fringe patterns were obtained from two approaches: (1) a single photodiode collected curved-edge interferometric fringe patterns by scanning the wafer edge and (2) an imaging device coupled with an objective lens captured the fringe image. The first approach allowed the wafer apex characterization, while the second approach enabled simultaneous localization and characterization of wafer quality along two bevels and apex directions. The collected fringe patterns were analyzed by both statistical feature extraction and wavelet transform; corresponding features were also evaluated through logarithm approximation. In sum, both proposed wafer-edge inspection methods can effectively characterize various wafer-edge defect modes. Their potential lies in their applicability to online wafer metrology and inspection applications, thereby contributing to the advancement of wafer manufacturing processes.
Wafer-Scale Fabrication of Quantum Photonic Devices in Silicon Carbide
We develop a wafer-scale process for nanofabrication of color center photonic devices in an arbitrary silicon carbide substrate using a reactive ion beam etching approach with a rotating tilted wafer.
more » « less- Award ID(s):
- 2047564
- PAR ID:
- 10481325
- Publisher / Repository:
- Optica Publishing Group
- Date Published:
- ISBN:
- 978-1-957171-29-6
- Page Range / eLocation ID:
- JTu5A.40
- Format(s):
- Medium: X
- Location:
- Tacoma, Washington
- Sponsoring Org:
- National Science Foundation
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