Today’s explosion of data urgently requires memory technologies capable of storing large volumes of data in shorter time frames,a feat unattain-able with Flash or DRAM.Intel Optane,commonly referred to as three-dimen...Today’s explosion of data urgently requires memory technologies capable of storing large volumes of data in shorter time frames,a feat unattain-able with Flash or DRAM.Intel Optane,commonly referred to as three-dimensional phase change memory,stands out as one of the most promising candidates.The Optane with cross-point architecture is constructed through layering a storage element and a selector known as the ovonic threshold switch(OTS).The OTS device,which employs chalcogenide film,has thereby gathered increased attention in recent years.In this paper,we begin by providing a brief introduction to the discovery process of the OTS phenomenon.Subsequently,we summarize the key elec-trical parameters of OTS devices and delve into recent explorations of OTS materials,which are categorized as Se-based,Te-based,and S-based material systems.Furthermore,we discuss various models for the OTS switching mechanism,including field-induced nucleation model,as well as several carrier injection models.Additionally,we review the progress and innovations in OTS mechanism research.Finally,we highlight the successful application of OTS devices in three-dimensional high-density memory and offer insights into their promising performance and extensive prospects in emerging applications,such as self-selecting memory and neuromorphic computing.展开更多
Restricted use of hazardous environmental chemicals is one important challenge that the semiconductor industry needs to face to improve its sustainability.Ovonic threshold switching(OTS)ternary compound materials used...Restricted use of hazardous environmental chemicals is one important challenge that the semiconductor industry needs to face to improve its sustainability.Ovonic threshold switching(OTS)ternary compound materials used in memory selector devices contain As and Se.Engineering these elements out of these materials requires significant research effort.To facilitate this process,we performed systematic material screening for As/Se-free ternary materials,based on ab-initio simulations.To limit the large amount of possible chemical compositions to fewer promising candidates,we used physics-based material parameter filters like material stability,electronic properties,or change in polarizability.The OTS gauge concept is introduced as a computed parameter to estimate the probability of a material to show an OTS behavior.As a result,we identified 35 As/Se-free ternary alloy compositions for stand-alone OTS memory applications,as well as 12 compositions for RRAM selector applications.This work aims seeding the development of As/Se-free OTS materials.展开更多
Two-dimensional(2D)ferromagnetic materials are considered as promising candidates for the future generations of spintronic devices.Yet,2D materials with intrinsic ferromagnetism are scarce.Hereby,high-throughput first...Two-dimensional(2D)ferromagnetic materials are considered as promising candidates for the future generations of spintronic devices.Yet,2D materials with intrinsic ferromagnetism are scarce.Hereby,high-throughput first-principles simulations are performed to screen 2D materials that present a non-magnetic to a ferromagnetic transition upon hole doping.A global evolutionary search is subsequently performed to identify alternative possible atomic structures of the eligible candidates,and 122 materials exhibiting a hole-doping induced ferromagnetism are identified.Their energetic and dynamic stability,as well as magnetic properties under hole doping are investigated systematically.Half of these 2D materials are metal halides,followed by chalcogenides,oxides,and nitrides,some of them having predicted Curie temperatures above 300 K.The exchange interactions responsible for the ferromagnetic order are also discussed.This work not only provides theoretical insights into hole-doped 2D ferromagnetic materials,but also enriches the family of 2D magnetic materials for possible spintronic applications.展开更多
基金M.Zhu acknowledges support by the National Outstanding Youth Program(62322411)the Hundred Talents Program(Chinese Academy of Sciences)+1 种基金the Shanghai Rising-Star Program(21QA1410800)The financial support was provided by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB44010200).
文摘Today’s explosion of data urgently requires memory technologies capable of storing large volumes of data in shorter time frames,a feat unattain-able with Flash or DRAM.Intel Optane,commonly referred to as three-dimensional phase change memory,stands out as one of the most promising candidates.The Optane with cross-point architecture is constructed through layering a storage element and a selector known as the ovonic threshold switch(OTS).The OTS device,which employs chalcogenide film,has thereby gathered increased attention in recent years.In this paper,we begin by providing a brief introduction to the discovery process of the OTS phenomenon.Subsequently,we summarize the key elec-trical parameters of OTS devices and delve into recent explorations of OTS materials,which are categorized as Se-based,Te-based,and S-based material systems.Furthermore,we discuss various models for the OTS switching mechanism,including field-induced nucleation model,as well as several carrier injection models.Additionally,we review the progress and innovations in OTS mechanism research.Finally,we highlight the successful application of OTS devices in three-dimensional high-density memory and offer insights into their promising performance and extensive prospects in emerging applications,such as self-selecting memory and neuromorphic computing.
基金This work was carried out in the framework of the imec Core CMOS-Active Memory Program.T.R.acknowledges the support by Research Foundation-Flanders(FWO)for providing the funding via strategic basic research PhD fellowship(grant no.1SD4721).
文摘Restricted use of hazardous environmental chemicals is one important challenge that the semiconductor industry needs to face to improve its sustainability.Ovonic threshold switching(OTS)ternary compound materials used in memory selector devices contain As and Se.Engineering these elements out of these materials requires significant research effort.To facilitate this process,we performed systematic material screening for As/Se-free ternary materials,based on ab-initio simulations.To limit the large amount of possible chemical compositions to fewer promising candidates,we used physics-based material parameter filters like material stability,electronic properties,or change in polarizability.The OTS gauge concept is introduced as a computed parameter to estimate the probability of a material to show an OTS behavior.As a result,we identified 35 As/Se-free ternary alloy compositions for stand-alone OTS memory applications,as well as 12 compositions for RRAM selector applications.This work aims seeding the development of As/Se-free OTS materials.
基金Part of this work has been financially supported by the FLAG-ERA grant DIMAG,by the Research Foundation—Flanders(FWO)as well as the KU Leuven Research Fund,project C14/17/080 and C14/21/083Part of the computational resources and services used in this work have been provided by the VSC(Flemish Supercomputer Center),funded by the FWO and the Flemish Government—department EWI.
文摘Two-dimensional(2D)ferromagnetic materials are considered as promising candidates for the future generations of spintronic devices.Yet,2D materials with intrinsic ferromagnetism are scarce.Hereby,high-throughput first-principles simulations are performed to screen 2D materials that present a non-magnetic to a ferromagnetic transition upon hole doping.A global evolutionary search is subsequently performed to identify alternative possible atomic structures of the eligible candidates,and 122 materials exhibiting a hole-doping induced ferromagnetism are identified.Their energetic and dynamic stability,as well as magnetic properties under hole doping are investigated systematically.Half of these 2D materials are metal halides,followed by chalcogenides,oxides,and nitrides,some of them having predicted Curie temperatures above 300 K.The exchange interactions responsible for the ferromagnetic order are also discussed.This work not only provides theoretical insights into hole-doped 2D ferromagnetic materials,but also enriches the family of 2D magnetic materials for possible spintronic applications.
