Abstract
The emergence of three-dimensional (3D) semiconductor devices has increased the importance of thermal imaging techniques. This paper presents a dual-capability system combining thermo-reflectance and thermal lock-in imaging (LIT) for high-speed, highly sensitive thermal analysis. We evaluate the hotspot detection capabilities of two-wavelength thermo-reflectance compared to LIT, including results from actual failure analysis cases. Our findings demonstrate the effectiveness of thermo-reflectance detection (TD) imaging for 3D devices where direct optical access to active layers is limited, such as 3D NAND flash memory and BSP-DN structured devices. This approach offers a promising solution for the thermal characterization of complex 3D semiconductor architectures.