Presentation Information
[11p-A13-2]Ultra-fast Resonant-Scanning Multiphoton-Excitation Photoluminescence Imaging of SiC Enabled by Nanosecond Band-Edge Emission
〇Toji Junichi1, Takashi Watanabe1, Tomoyuki Tanikawa2 (1.NIKON Corp., 2.Meijo Univ.)
Keywords:
defect evaluation,multiphoton-excited photoluminescence,imaging
Silicon carbide (SiC) is a promising wide-bandgap semiconductor for power devices, but crystal defects (threading dislocations, basal plane dislocations, stacking faults) degrade performance and reliability, so nondestructive, high-throughput wafer-scale defect evaluation is needed. Photoluminescence (PL) imaging is widely used, yet wide-field PL lacks sufficient spatial resolution and confocal PL is limited by slow scanning. Multiphoton-excited PL (MPPL) provides high spatial resolution by confining excitation to the focal region, but conventional MPPL typically uses galvanometer scanners whose mechanical limits restrict acquisition speed.This study leverages the nanosecond-scale band-edge PL dynamics of SiC and implements MPPL imaging with a resonant scanner. The resonant scanner in a commercial Nikon multiphoton microscope achieves imaging rates about 30 times faster than galvanometer-based scanning, substantially reducing measurement time. MPPL imaging of SiC band-edge emission shows clear dark-spot contrast corresponding to threading dislocations. Because SiC band-edge PL lifetimes are on the nanosecond scale, sufficient signal is obtained even with the short pixel dwell times of resonant scanning, and no significant signal persistence from previous pixels was observed. As a result, emission maps of roughly 70 μm × 70 μm areas can be acquired in tens of milliseconds, demonstrating rapid defect imaging.These findings indicate that SiC’s MPPL band-edge dynamics are compatible with the fast scanning conditions of resonant scanners, making this method a promising high-throughput, nondestructive defect evaluation technique. Combined with wide-field PL mapping, it can support both wafer-scale defect distribution analysis and localized structural characterization, and is expected to be applicable to SiC and other wide-bandgap semiconductor materials.