Search Results - "Toriumi, Akira"

Stepwise internal potential jumps caused by multiple-domain polarization flips in metal/ferroelectric/metal/paraelectric/metal stack by Li, Xiuyan, Toriumi, Akira

“…Negative capacitance (NC) effects in ferroelectric/paraelectric (FE/PE) stacks have been recently discussed intensively in terms of the steep subthreshold…”
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Origin of electric dipoles formed at high-k/SiO2 interface by Kita, Koji, Toriumi, Akira

“…A model for the physical origin of the dipole formed at high-k/SiO2 interface is proposed. In our model, an areal density difference of oxygen atoms at…”
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Evolution of ferroelectric HfO2 in ultrathin region down to 3 nm by Tian, Xuan, Shibayama, Shigehisa, Nishimura, Tomonori, Yajima, Takeaki, Migita, Shinji, Toriumi, Akira

“…The ferroelectric properties of ultrathin Y-doped HfO2 films were investigated. Ferroelectricity was demonstrated experimentally in 3 nm-thick Y-doped HfO2 via…”
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Polarization switching in thin doped HfO2 ferroelectric layers by Materano, Monica, Lomenzo, Patrick D., Mulaosmanovic, Halid, Hoffmann, Michael, Toriumi, Akira, Mikolajick, Thomas, Schroeder, Uwe

“…The deployment of ferroelectrics in device concepts such as Ferroelectric Random Access Memory and Ferroelectric Field Effect Transistors requires a good…”
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Evidence for strong Fermi-level pinning due to metal-induced gap states at metal/germanium interface by Nishimura, Tomonori, Kita, Koji, Toriumi, Akira

“…The purpose of this paper is to understand metal/germanium (Ge) junction characteristics. Electrode metals with a wide work function range were deposited on…”
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Interface reaction kinetics in SiGe oxidation by Li, Xiuyan, Noma, Yusuke, Song, Woojin, Nishimura, Tomonori, Toriumi, Akira

“…The oxidation of SiGe is very different from that of Si or Ge, leading to poor interface quality in oxidized SiGe gate stacks. In this work, SiGe oxidation…”
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Polarization switching behavior of Hf-Zr-O ferroelectric ultrathin films studied through coercive field characteristics by Migita, Shinji, Ota, Hiroyuki, Yamada, Hiroyuki, Shibuya, Keisuke, Sawa, Akihito, Toriumi, Akira

“…The electrical properties of ferroelectric Hf-Zr-O ultrathin films, particularly the dependences of remnant polarization, leakage current, coercive field, and…”
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Density-of-States Limited Contact Resistance in Graphene Field-Effect Transistors by Nagashio, Kosuke, Toriumi, Akira

“…Graphene has attracted much attention as one of promising candidates of future high-speed transistor materials because of its high carrier mobility of more…”
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Impacts of oxygen passivation on poly-crystalline germanium thin film transistor by Kabuyanagi, Shoichi, Nishimura, Tomonori, Nagashio, Kosuke, Toriumi, Akira

“…We investigated the effects of the annealing ambient during solid phase crystallization (SPC) on the crystallization temperature of amorphous Ge and the…”
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Recent progress for obtaining the ferroelectric phase in hafnium oxide based films: impact of oxygen and zirconium by Schroeder, Uwe, Materano, Monica, Mittmann, Terence, Lomenzo, Patrick D., Mikolajick, Thomas, Toriumi, Akira

“…Different causes for ferroelectric properties in hafnium oxide were discussed during the last decade including various dopants, stress, electrode materials,…”
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Ferroelectricity of nondoped thin HfO2 films in TiN/HfO2/TiN stacks by Nishimura, Tomonori, Xu, Lun, Shibayama, Shigehisa, Yajima, Takeaki, Migita, Shinji, Toriumi, Akira

“…We report on the impact of TiN interfaces on the ferroelectricity of nondoped HfO2. Ferroelectric properties of nondoped HfO2 in TiN/HfO2/TiN stacks are shown…”
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Observation of the Pinch‐Off Effect during Electrostatically Gating the Metal‐Insulator Transition by Yajima, Takeaki, Toriumi, Akira

“…Electrostatically controlling material phases has been a long‐standing challenge. While it is partially achieved by electrostatic gating with ionic liquid, it…”
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Interfacial SiO2 scavenging kinetics in HfO2 gate stack by Li, Xiuyan, Nishimura, Tomonori, Toriumi, Akira

“…In this paper, Si and oxygen diffusions as well as SiO2 reduction reaction in HfO2/SiO2/Si stacks are examined in detail for fully understanding the SiO2-IL…”
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Phase transformation behavior of ultrathin Hf0.5Zr0.5O2 films investigated through wide range annealing experiments by Migita, Shinji, Ota, Hiroyuki, Shibuya, Keisuke, Yamada, Hiroyuki, Sawa, Akihito, Matsukawa, Takashi, Toriumi, Akira

“…Hf0.5Zr0.5O2 thin films are not always ferroelectric. This work investigates the impact of annealing temperature and time on the crystalline structures and…”
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Identifying the Collective Length in VO2 Metal–Insulator Transitions by Yajima, Takeaki, Nishimura, Tomonori, Toriumi, Akira

“…The “collective length” in VO2 metal–insulator transitions is identified by controlling nanoscale dopant distribution in thin films. The crossover from the…”
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Thermodynamic understanding and analytical modeling of interfacial SiO2 scavenging in HfO2 gate stacks on Si, SiGe, and SiC by Li, Xiuyan, Yajima, Takeaki, Nishimura, Tomonori, Toriumi, Akira

“…This work thermodynamically and experimentally generalizes the interfacial SiO2 scavenging in HfO2 gate stacks from on Si to on other channel materials…”
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Moisture-absorption-induced permittivity deterioration and surface roughness enhancement of lanthanum oxide films on silicon by Zhao, Yi, Toyama, Masahiro, Kita, Koji, Kyuno, Kentaro, Toriumi, Akira

“…Effects of moisture absorption on permittivity and surface roughness of lanthanum oxide ( La 2 O 3 ) films were investigated. It was found that the moisture…”
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Design points of ferroelectric field-effect transistors for memory and logic applications as investigated by metal-ferroelectric-metal-insulator-semiconductor gate stack structures using Hf0.5Zr0.5O2 films by Migita, Shinji, Ota, Hiroyuki, Toriumi, Akira

“…The potential of ferroelectric field-effect transistors (FeFETs) was investigated in regard to memory and logic applications. Integrating ferroelectric…”
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Effect of Si substrate on interfacial SiO2 scavenging in HfO2/SiO2/Si stacks by Li, Xiuyan, Yajima, Takeaki, Nishimura, Tomonori, Nagashio, Kosuke, Toriumi, Akira

“…The scavenging kinetics of an ultra-thin SiO2 interface layer (SiO2-IL) in an HfO2/SiO2/Si stack is discussed by focusing on the substrate effect in addition…”
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Independent control of phases and defects in TiO2 thin films for functional transistor channels by Yajima, Takeaki, Oike, Go, Nishimura, Tomonori, Toriumi, Akira

“…TiO2 has various inherent advantages in practical devices: chemical stability, non‐toxicity, and abundance on earth, as highlighted in a range of applications…”
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