Effect of N dopants on the phase change characteristics of Cr2Ge2Te6 film revealed by changes in optical properties

In this study, the microstructure, optical properties, and crystallization kinetics of N-doped Cr2Ge2Te6 (NCrGT) phase change materials (PCMs) were investigated. The NCrGT films exhibited a reflectance decrease upon crystallization, which is opposite to the behavior of CrGT and traditional PCMs, such as Ge2Sb2Te5. Additionally, the N dopants were confirmed to accelerate the crystallization speed of CrGT. Furthermore, the crystallized spots on the NCrGT films were found to be reamorphized by laser irradiation at a lower power than is required for CrGT, indicating a reversible laser pulse-induced phase transition and a lower thermal cost resulting from the incorporation of N. The faster crystallization speed of the NCrGT films originated from their shorter incubation time and simplified crystallization process tuned by the local bonding configuration close to N atoms. Our findings demonstrate that adding N dopants can dramatically alter the optical properties of CrGT, leading to faster crystallization and reduced power consumption.

Automated summary

This study investigated the microstructure, optical properties, and crystallization kinetics of N-doped Cr2Ge2Te6 (NCrGT) phase change materials (PCMs). The NCrGT films exhibited a decrease in reflectance upon crystallization, and the N dopants accelerated the crystallization speed of CrGT. Laser irradiation could induce a reversible phase transition in the crystallized spots on the NCrGT films, indicating a lower thermal cost. The faster crystallization speed of NCrGT films resulted from their shorter incubation time and simplified crystallization process.