Thermal-optical readout of multi-level thermal emissivity Ge2Sb2Te5 patterns

• NCJ Number: 303254
• Author(s): M. Wang; M. Su
• Date Published: 2019
• Grant Number(s): 2012-DN-BX-K021
• Agencies: NIJ-Sponsored
• Award: Encapsulated phase change nanoparticles as thermally-readable covert taggants

Annotation

This article describes thermal-optical readout of multilevel thermal emissivity Ge2Sb2Te5 patterns. 

Abstract

Ge2Sb2Te5 thin film (100 nm) can be patterned with multi-level crystalline and thermal emissivity states using laser in large scale. Various patterns can be fabricated by tuning laser power and speed. X-ray diffraction (XRD) and infrared analysis results show that Ge2Sb2Te5 thin film has different thermal emissivity at different crystalline states. In-situ repeated heating of the Ge2Sb2Te5 thin film confirms the tendency between crystalline and thermal emissivity. Both the infrared image and thermal emissivity can be readout by infrared camera. The colorful infrared image enables easily identification of Ge2Sb2Te5 crystallite change. (publisher abstract modified)