R&D: Ultrasonic and Structural Characterization of Ge2Sb2Te6 – GST Phase-Change Materials for Memory Applications

Materials Research Express has published an article written by Nicoleta Stan, Institute of Solid Mechanics, Romanian Academy; 15 C-tin Mille, Bucharest 010141, Romania, Nicoleta Nedelcu, Department of Chemistry & Physics, Mount Royal University, 4825 Mount Royal Gate S.W. Calgary, Alberta T3E 6K6, Canada, Veturia Chiroiu, Institute of Solid Mechanics, Romanian Academy; 15 C-tin Mille, Bucharest 010141, Romania, Cristian Rugină, Institute of Solid Mechanics, Romanian Academy; 15 C-tin Mille, Bucharest 010141, Romania, andINCAS National Institute for Aerospace Research Elie Carafoli, Iuliu Maniu 220, Sector 6, 061126, Bucharest, Romania, Ana Maria Mitu, Institute of Solid Mechanics, Romanian Academy; 15 C-tin Mille, Bucharest 010141, Romania, and Arcadie Sobetkii, MGM Star Construct SRL, 7 Pincota Str., 022773, Bucharest, Romania.

Abstract: “This study explores ultrasonic non-destructive testing (NDT) to determine the elastic properties of Ge2Sb2Te6 – GST, a phase-change material widely used in data storage technologies. Ultrasonic measurements were conducted to determine both longitudinal and transverse velocities. Mechanical parameters, including Young’s modulus and Poisson’s ratio, were calculated and confirm the accuracy and reliability of ultrasonic testing in characterizing the elastic behavior of Ge2Sb2Te6-GST. X-ray diffraction analysis reveals well-defined peaks corresponding to the face-centered cubic (fcc) phase of Ge2Sb2Te6 – GST. The average crystallite size was estimated using the Scherrer equation, and the quantitative EDX analysis provided reveals the sample’s elemental composition in both mass % and atomic %. This approach offers a precise, non-invasive method for evaluating phase-change materials and supports its broader application in materials science and electronic device development.“