Phase transition characteristics of Bi/Sn doped Ge2Sb2Te5thin film for PRAM application

High-Temperature Complex Refractive Index of Phase Change Recording Medium of Ge2Sb2Te5 Determined Using Phase Change Static Tester and Spectroscopic Ellipsometer

“…The complex refractive indices of the as-deposited GST thin film ( As-Depo) and the GST thin film irradiated with a laser power of less than 18 mW agree well with the reference n and k of the amorphous one ( Amor-GST-Ref). Those of GST thin films are in good agreement with the reference n and k of the crystalline GST thin film ( Cry-GST-Ref, which has an hcp structure and remains in a stable crystalline state 13) before the temperature reaches the melting point) as the laser power increases to more than 18 mW up to 45 mW, regardless of the protective layer used. The laser power of 45 mW corresponds to the heating temperature of $450 C. It is considered that a crystallization of GST samples without causing damage to the samples is made possible, since the Te and Sb atoms have neither a sufficient energy to escape from Ge 2 Sb 2 Te 5 nor a sufficient time to chemically react with the protective layer, because the GST samples were locally crystallized within tens of nanoseconds by the PRAM method.…”

Scalable High-Performance Phase-Change Memory Employing CVD GeBiTe

“…The SET falling time of the GST cell was observed to be 500 ns for the fully crystalline state, whereas the GBT1 cell was fully crystallized within 3 ns. The significant improvement of the crystallization speed by CVD GBT is explained by the metallic interatomic binding induced by the unpinning of the Fermi level induced by the small amount of Bi in GBT, and the reduced sensing margin with the increased Bi concentration originates from the increased amorphous conductivity of GBT, along with the increased Bi concentration [6], [10]- [12]. Fig.…”

Phase-change control of ferromagnetism in GeTe-based phase change magnetic thin-films by pulsed laser deposition

“…This phenomenon is similar to the previous observation in metal doped Ge 2 Sb 2 Te 5 . 7,16 The magnetization curves for the three states (C 0 , A, and C a ) at 2 K with a magnetic field parallel to the film surface are shown in Fig. 2.…”