A5088072096- Phase-change materials and chalcogenides
- Semiconductor materials and devices
- Chalcogenide Semiconductor Thin Films
- Advancements in Semiconductor Devices and Circuit Design
- Liquid Crystal Research Advancements
- Integrated Circuits and Semiconductor Failure Analysis
- Nonlinear Optical Materials Studies
- Transition Metal Oxide Nanomaterials
- Advanced Memory and Neural Computing
- Metal and Thin Film Mechanics
- Semiconductor materials and interfaces
- Copper Interconnects and Reliability
- Silicon Carbide Semiconductor Technologies
- Thin-Film Transistor Technologies
- Quantum Dots Synthesis And Properties
- Electronic Packaging and Soldering Technologies
- Advanced ceramic materials synthesis
- Glass properties and applications
- Electrophoretic Deposition in Materials Science
- Ferroelectric and Negative Capacitance Devices
- Photoreceptor and optogenetics research
- Electrodeposition and Electroless Coatings
- Molecular Junctions and Nanostructures
- Nanowire Synthesis and Applications
- Crystal Structures and Properties
Université Grenoble Alpes
2012-2024
CEA LETI
2012-2024
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2013-2024
CEA Grenoble
2011-2023
Institut polytechnique de Grenoble
2007-2016
Centre National de la Recherche Scientifique
2003-2014
Université Joseph Fourier
2014
Laboratoire National des Champs Magnétiques Intenses
2014
European Synchrotron Radiation Facility
2009
STMicroelectronics (France)
2009
Abstract Chalcogenide phase-change materials (PCMs), such as Ge-Sb-Te alloys, have shown outstanding properties, which has led to their successful use for a long time in optical memories (DVDs) and, recently, non-volatile resistive memories. The latter, known PCM or random access (PCRAMs), are the most promising candidates among emerging memory (NVM) technologies replace current FLASH at CMOS technology nodes under 28 nm. PCMs exhibit fast and reversible phase transformations between...
In this paper, we investigate the impact of Ge-enrichment coupled to N- or C-doping in Ge <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Sb Te xmlns:xlink="http://www.w3.org/1999/xlink">5</sub> based materials on low-resistance state (LRS SET) performance combined with high-resistance (HRS RESET) high-temperature data retention (HTDR) Phase-Change Memories (PCM). These innovative have been integrated state-of-the-art memory cell...
The commercialization of Phase-Change Memories (PCM), based on the well-known GST compound, have been recently started, tailored for consumer applications. Despite other excellent performances (i.e. low-power, scalability,...), data retention is assured up to 85°C, still limited automotive market segment. Alternative active material able comply with stringent requirements applications should possibly exhibit higher crystallization temperature (T <sub...
The development of Ge-rich GeSbTe (GGST) alloys significantly enhanced the high-temperature stability required for Phase-Change Memory technology. Previous studies on Ge enrichment in (GST) materials with Sb-over-Te ratio lower than one (Sb/Te&lt;1) highlighted segregation into cubic and GST phases. Such a segregated phase is metastable presents polycrystalline structure disordered grain boundaries that could lead to structural relaxation then drift phenomena. In this work, using...
The thermal conductivity and boundary resistance of GeTe carbon doped thin films, designed for phase change memory (PCM) applications, were investigated by modulated photo radiometry. It was found that C doping has no significant effect on the these chalcogenides in amorphous state. between films SiO2 substrate is also not affected doping. then crystallized an annealing at 450°C as confirmed optical reflectivity analysis. non-doped significantly increases after crystallization annealing....
In this paper we analyze recent progress in Phase- Change Memory (PCM) technology targeting both Storage Class and embedded applications. The challenge to achieve a high temperature data retention without compromising the device programming speed can be addressed by material engineering. We show that volume thermal confinement improvement of phase-change enables (10-fold) reduction current, achieved also optimization architecture, particular case confined structure. It leads higher cell...
Ge-rich GeSbTe alloys allowed overcoming temperature limitations of phase-change memory technology. In this paper, we present a thorough investigation the structural evolution and crystallization process these as function increasing in annealing. We highlight progressive rearrangement structure toward demixing Ge phases. particular, show stability Sb–Te units development Ge–Te bonds around features. observe formation transient phase, which is driven by phenomena, leading to gradual diffusion...
In this paper we investigate the impact of N- doping in optimized Ge-rich Ge2Sb2Te5 materials on device programming and storing performance. We integrate these alloys state-of-the-art Phase- Change Memory (PCM) cells analyze efficiency SET operation N-doped undoped memory cells, comparing voltage based with current programming. This aspect is extensively investigated through electrical characterization, physico-chemical analysis electro-thermal simulations. The thermal stability devices...
The crystallization behavior of Ge2Sb2Te5 nanometric clusters was studied using X-ray diffraction with in situ annealing. Clusters were made a sputtering gas-phase condensation source, which allowed for the growth well-defined, contaminant-free, and isolated clusters. average size is 5.7 ± 1 nm. As-deposited amorphous crystallize fcc cubic phase at 180 °C, while thin films, change temperature 155 °C. This observation illustrates scalability from to state three-dimensionally confined systems...
The phase change from the amorphous to crystalline state which occurs upon thermal annealing in prototypical Ge 2 Sb Te 5 and nitrogen-doped phase-change-materials (PCM) thin films is studied by concomitant, complementary combined situ ex X-ray diffraction (XRD) reflectivity (XRR) techniques. It demonstrated that scattering techniques allow accurate investigation clarification of structural, morphological mechanical variations occurring crystallization. crystallization process correlated...
In this paper, we present a thorough physical-chemical analysis of an engineered PCM stack, where the integration C-doping and use Ti top layer allow obtaining Amorphous As-Deposited (A-AD) phase stable against Back End-Of-Line (BEOL) thermal budget. This stack is then integrated in devices, which are extensively tested order to validate novel pre-coding technique compliant Pb-free soldering reflow issue. Finally, original design optimize distribution dispersion presented.
In this paper, we investigate the impact of thermal budget and thickness on chemical electronic properties stack. High temperature anneal at induces both regrowth reoxidation interfacial layer. A bias drop 1.1 eV is observed along whole stack via C 1s core-level shift ascribed to dipole fixed charges in . Electrical measurements suggest a strength 0.2 eV. Ellipsometry UV photoelectron spectroscopy are combined deduce electron affinity This value does not change with increasing or dielectric...
In this paper we present the engineering of highly Sb-rich Ge-Sb-Te phase-change materials integrated in state-of-the-art Phase-Change Memory devices 4Kb arrays. Thanks to an innovative composition called "delta" or δ-GST, high speed performance and material stability under cycling is achieved arrays demonstrated by both physicochemical analysis electrical characterization. Finally, origin outstanding our compound revealed.
We have investigated the dependence of effective work function (EWF) a poly-p+∕TiN∕SiO2∕Si capacitor as TiN layer thickness. By using pulsing chemical vapor deposition process, nitride was demonstrated to be continuous from 2.2nm. It also shown that EWF capacitors, made with thickness ranging between 2.2 and 7.1nm, is independent similar bulk TiN. Our study indicates entire gate electrode stack determined by first metallic monolayers (&lt;2.2nm) in contact dielectric.
The crystallization of amorphous GeTe and Ge2Sb2Te5 phase change material films, with thickness between 10 100 nm, sandwiched either Ta or SiO2 layers, was investigated by optical reflectivity. cladding layers were found to increase the temperature, even for films as thick nm. X-Ray diffraction investigations crystallized showed a very weak texture in cladded contrast strong observed layers. This study shows that mechanism materials can be highly impacted interface effects, relatively films.