Carbon-doped Ge2Sb2Te5 (GSTC) film has been experimentally studied as a thermal stable material for high temperature applications. The 10-yr data retention temperature is remarkably increased through C doping. Furthermore, GSTC films have better interface properties after annealing at 410 °C for 30 min. The density variation of GSTC film is significantly improved, which is very important to device reliability. X-ray photoelectron spectroscopy results reveal that the thermal stability enhancement of GSTC film attributes to the forming of C-Ge, C-Sb, and C-Te bonds. The perfect thermal stability makes GSTC materials a good candidate in the actual production of phase-change memory.

High thermal stability and low density variation of carbon-doped Ge2Sb2Te5 for phase-change memory application

The crystallization behavior of Al-Sb thin films is investigated for phase change memory application. The crystallization temperature and optical band gap of the amorphous material increase with Al content. The thermal stability and randomness in atomic configuration of the films are enhanced considerably. The shift of Raman modes associated mainly with Sb upon phase transformation is observed, and the co-existence of Sb-rich crystalline regions and Al-rich amorphous matrix is confirmed, revealing the amorphous nature of most Al components. Three distinct resistance levels are achieved in the devices using Al50Sb50, suggesting the potentiality for multilevel data storage application of the materials.

Phase transition characteristics of Al-Sb phase change materials for phase change memory application

ZnxSb100−x films with low Zn content are crystallized in a single-step process with Sb, while the film (Zn/Sb ratio is about 1:1) exhibits a two-step crystallization process with ZnSb metastable and stable phases. Importantly, ZnSb films have higher crystallization temperature (~257 °C), larger crystalline activation energy (~5.63 eV), better 10 year-data-retention (~201 °C) and lower melting temperature (~500 °C).

Crystallization behaviors of ZnxSb100−x thin films for ultralong data retention phase change memory applications

The environmental mobility and bioavailability of antimony (Sb) are strongly influenced by sorption to Fe(III) oxide minerals, such as goethite (αFeOOH). Exposure to aqueous Fe(II), as occurs, for ...

Antimony Sorption to Goethite: Effects of Fe(II)-Catalyzed Recrystallization

W-Sb-Te phase-change material has been proposed to improve the performance of phase-change memory (PCM). Crystallization temperature, crystalline resistance, and 10-year data retention of Sb2Te increase markedly by W doping. The Wx(Sb2Te)1−x films crystallize quickly into a stable hexagonal phase with W uniformly distributing in the crystal lattice, which ensures faster SET speed and better operation stability for the application in practical device. PCM device based on W0.07(Sb2Te)0.93 shows ultrafast SET operation (6 ns) and good endurance (1.8 × 105 cycles). W-Sb-Te material is a promising candidate for the trade-off between programming speed and data retention.

W-Sb-Te phase-change material: A candidate for the trade-off between programming speed and data retention

Antimony alloys for phase-change memory with high thermal stability

The use of Ga16Sb84 alloy for electronic phase-change memory

Phase transformation in Mg–Sb thin films

Upon decreasing ultra-thin Ga16Sb84 films from 10 to 3 nm, the exponential increase in crystallization temperature and electrical resistance ratio are attributed to increased specific interface-energies and inhomogeneous interfacial strain at the interfaces. The specific interface-energies and strain also stabilize the Sb(Ga) phase and suppress phase-separation of the GaSb phase.

Chih-Chung Chang

Papers

Antimony alloys for phase-change memory with high thermal stability

The use of Ga16Sb84 alloy for electronic phase-change memory

Phase transformation in Mg–Sb thin films

Crystallization behaviors of an ultra-thin Ga–Sb film

Ga19Sb81 film for multi-level phase-change memory