Optical inspection machine Candela® 8520

surfacehard disk drive (HDD)for the electronics industry

The Candela® 8520 second generation integrated photoluminescence (PL) and surface inspection system is designed for advanced characterization of substrate and epitaxial defects on SiC and GaN substrates. It captures topographic variations, surface reflectance, phase shift and photoluminescence for automatic detection and classification of a broad range of defects of interest (DOI). This system employs proprietary optical technology to simultaneously measure scatter intensity at two angles of incidence. The Candela 8520 provides surface and photoluminescence defect inspection for GaN wafers, detecting and classifying GaN dislocations, pits and holes for GaN reactor defect control. Power applications include SiC based transparent wafer inspection and classification of crystal defects such as BPDs (Basal Plane Dislocations), micropipes, stacking faults, bar stacking faults, grain boundaries, and threading dislocations. Detection of topographic anomalies include triangle detection, carrot defects, downfall and scratches. Substrate quality control, substrate vendor comparison, incoming wafer quality control (IQC), outgoing wafer quality control (IQC), CMP (chemical mechanical process) / polishing process control, wafer clean process control, epitaxy process control, substrate to epitaxy correlation, epitaxy reactor vendor comparison, process tool monitoring. Detects surface defects on Wide Band Gap materials including SiC and GaN (substrate and epitaxy) up to 200mm in diameter Supports a wide range of wafer thickness Detects particles, scratches, cracks, stains, pits, bumps, KOH etch mapping