Large voltage-induced coercivity change in Pt/Co/CoO/amorphous TiOx structure and heavy metal insertion effect

AbstractThere is urgent need for spintronics materials exhibiting a large voltage modulation effect to fulfill the great demand for high-speed, low-power-consumption information processing systems. Fcc-Co (111)-based systems are a promising option for research on the voltage effect, on account of their large perpendicular magnetic anisotropy (PMA) and high degree of freedom in structure. Aiming to observe a large voltage effect in a fcc-Co (111)-based system at room temperature, we investigated the voltage-induced coercivity (Hc) change of perpendicularly magnetized Pt/heavy metal/Co/CoO/amorphous TiOx structures. The thin CoO layer in the structure was the result of the surface oxidation of Co. We observed a large voltage-induced Hc change of 20.2 mT by applying 2 V (0.32 V/nm) to a sample without heavy metal insertion, and an Hc change of 15.4 mT by applying 1.8 V (0.29 V/nm) to an Ir-inserted sample. The relative thick Co thickness, Co surface oxidation, and large dielectric constant of TiOx layer could be related to the large voltage-induced Hc change. Furthermore, we demonstrated the separate adjustment of Hc and a voltage-induced Hc change by utilizing both upper and lower interfaces of Co.

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Large Voltage-Induced Coercivity Change in Pt/Co/CoO/Amorphous TiOx Structure and Heavy Metal Insertion Effect

10.21203/rs.3.rs-798923/v1 ◽

2021 ◽

Author(s):

Tomohiro Nozaki ◽

Shingo Tamaru ◽

Makoto Konoto ◽

Takayuki Nozaki ◽

Hitoshi Kubota ◽

...

Keyword(s):

Heavy Metal ◽

High Speed ◽

Room Temperature ◽

Perpendicular Magnetic Anisotropy ◽

Surface Oxidation ◽

Low Power Consumption ◽

Oxidation Of Co ◽

Large Dielectric Constant ◽

Metal Insertion ◽

High Degree

Abstract There is urgent need for spintronics materials exhibiting a large voltage modulation effect to fulfill the great demand for high-speed, low-power-consumption information processing systems. Fcc-Co (111)-based systems are a promising option for research on the voltage effect, on account of their large perpendicular magnetic anisotropy (PMA) and high degree of freedom in structure. Aiming to observe a large voltage effect in a fcc-Co (111)-based system at room temperature, we investigated the voltage-induced coercivity (Hc) change of a perpendicularly magnetized Pt/heavy metal/Co/CoO/amorphous TiOx structure. The thin CoO layer in the structure was the result of the surface oxidation of Co. We observed a large voltage-induced Hc change of 20.2 mT by applying 2 V (0.32 V/nm) to a sample without heavy metal insertion, and an Hc change of 15.4 mT by applying 1.8 V (0.29 V/nm) to an Ir-inserted sample. The relative thick Co thickness, Co surface oxidation, and large dielectric constant of TiOx layer could be related to the large voltage-induced Hc change. Furthermore, we demonstrated the separate adjustment of Hc and a voltage-induced Hc change by utilizing both upper and lower interfaces of Co.

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Design rules for scalability in spin-orbit electronics

Scientific Reports ◽

10.1038/s41598-019-49831-5 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Mohammad Kazemi ◽

Mark F. Bocko

Keyword(s):

Heavy Metal ◽

Power Consumption ◽

Low Power ◽

Topological Insulator ◽

Room Temperature ◽

Ferromagnetic Layer ◽

Thermal Fluctuations ◽

Low Power Consumption ◽

Spin Orbit ◽

Design Rules

Abstract Spin-orbit electronics (spin-orbitronics) has been widely discussed for enabling nonvolatile devices that store and process information with low power consumption. The potential of spin-orbitronics for memory and logic applications has been demonstrated by perpendicular anisotropy magnetic devices comprised of heavy-metal/ferromagnet or topological-insulator/ferromagnet bilayers, where the heavy metal or topological insulator provides an efficient source of spin current for manipulating information encoded in the bistable magnetization state of the ferromagnet. However, to reliably switch at room temperature, spin-orbit devices should be large to reduce thermal fluctuations, thereby compromising scalability, which in turn drastically increases power dissipation and degrades performance. Here, we show that the scalability is not a fundamental limitation in spin-orbitronics, and by investigating the interactions between the geometry of the ferromagnetic layer and components of the spin-orbit torque, we derive design rules that lead to deeply scalable spin-orbit devices. Furthermore, employing experimentally verified models, we propose deeply scaled spin-orbit devices exhibiting high-speed deterministic switching at room temperature. The proposed design principles are essential for design and implementation of very-large-scale-integration (VLSI) systems that provide high performance operation with low power consumption.

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TEM study of phosphorus-implanted pseudomorphic Si0.88Ge0.12 on Si(100)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138713 ◽

1995 ◽

Vol 53 ◽

pp. 468-469

Author(s):

N. David Theodore ◽

Donald Y.C Lie ◽

J. H. Song ◽

Peter Crozier

Keyword(s):

Integrated Circuits ◽

Heterojunction Bipolar Transistors ◽

Integrated Circuit ◽

High Speed ◽

Room Temperature ◽

Strain Relaxation ◽

Bipolar Transistors ◽

Sige Hbt ◽

Integrated Circuit Manufacturing ◽

Microstructural Behavior

SiGe is being extensively investigated for use in heterojunction bipolar-transistors (HBT) and high-speed integrated circuits. The material offers adjustable bandgaps, improved carrier mobilities over Si homostructures, and compatibility with Si-based integrated-circuit manufacturing. SiGe HBT performance can be improved by increasing the base-doping or by widening the base link-region by ion implantation. A problem that arises however is that implantation can enhance strain-relaxation of SiGe/Si.Furthermore, once misfit or threading dislocations result, the defects can give rise to recombination-generation in depletion regions of semiconductor devices. It is of relevance therefore to study the damage and anneal behavior of implanted SiGe layers. The present study investigates the microstructural behavior of phosphorus implanted pseudomorphic metastable Si0.88Ge0.12 films on silicon, exposed to various anneals.Metastable pseudomorphic Si0.88Ge0.12 films were grown ~265 nm thick on a silicon wafer by molecular-beam epitaxy. Pieces of this wafer were then implanted at room temperature with 100 keV phosphorus ions to a dose of 1.5×1015 cm-2.

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Ultracompact and low-power-consumption silicon thermo-optic switch for high-speed data

Nanophotonics ◽

10.1515/nanoph-2020-0496 ◽

2020 ◽

Vol 10 (2) ◽

pp. 937-945

Author(s):

Ruihuan Zhang ◽

Yu He ◽

Yong Zhang ◽

Shaohua An ◽

Qingming Zhu ◽

...

Keyword(s):

Power Consumption ◽

Low Power ◽

High Speed ◽

High Performance ◽

Pulse Amplitude ◽

Telecommunication Networks ◽

Low Power Consumption ◽

Power Efficient ◽

High Speed Data ◽

On Chip

AbstractUltracompact and low-power-consumption optical switches are desired for high-performance telecommunication networks and data centers. Here, we demonstrate an on-chip power-efficient 2 × 2 thermo-optic switch unit by using a suspended photonic crystal nanobeam structure. A submilliwatt switching power of 0.15 mW is obtained with a tuning efficiency of 7.71 nm/mW in a compact footprint of 60 μm × 16 μm. The bandwidth of the switch is properly designed for a four-level pulse amplitude modulation signal with a 124 Gb/s raw data rate. To the best of our knowledge, the proposed switch is the most power-efficient resonator-based thermo-optic switch unit with the highest tuning efficiency and data ever reported.

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Improvement of Gas Sensing of Uniform Ag 3 PO 4 Nanoparticles to NH 3 under the Assistant of LED Lamp with Low Power Consumption at Room Temperature

ChemistrySelect ◽

10.1002/slct.202101592 ◽

2021 ◽

Vol 6 (32) ◽

pp. 8338-8344

Author(s):

Xingyan Shao ◽

Shuo Wang ◽

Leqi Hu ◽

Tingting Liu ◽

Xiaomei Wang ◽

...

Keyword(s):

Power Consumption ◽

Low Power ◽

Room Temperature ◽

Gas Sensing ◽

Low Power Consumption

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Hydrogeochemistry and surface water quality assessment of IB valley coalfield area, India

Applied Water Science ◽

10.1007/s13201-021-01433-1 ◽

2021 ◽

Vol 11 (9) ◽

Author(s):

Bishnu Prasad Sahoo ◽

Himanshu Bhushan Sahu ◽

Dhruti Sundar Pradhan

Keyword(s):

Water Quality ◽

Heavy Metal ◽

Seasonal Variation ◽

Surface Water ◽

Water Samples ◽

Nickel Aluminum ◽

Acid Mine ◽

Significant Seasonal Variation ◽

Cadmium Selenium ◽

High Degree

AbstractCoal mining and ancillary activities have the potential to cause water pollution characterized by acid mine drainage, acid mine leachates, extreme pH conditions and heavy metal contaminations. In the present work, 33 water samples in premonsoon and 34 water samples in monsoon were collected from the surface water bodies of Ib Valley coalfield, India for hydrogeochemical analysis. In premonsoon, pH, TSS, Turbidity, DO, BOD, COD, Magnesium, Cadmium, Selenium, Nickel, Aluminum and in monsoon, pH, TSS, Turbidity, DO, BOD, COD, Iron, Cadmium, Selenium, Nickel and Aluminum were nonconforming to the permissible limit set by the Bureau of Indian Standards, World Health Organisation and Ministry of Environment, Forest and Climate Change, Government of India. The average BOD/COD ratio of less than 0.6 in both seasons indicated Ib valley coalfield water was not fairly biodegradable. The analysis of variance (ANOVA) revealed that significant seasonal variation (p < 0.05) was observed in the hydro-chemical parameters viz. TSS, turbidity, redox potential, acidity, total hardness, bicarbonate alkalinity, chloride, sulfate, nitrate, sodium, calcium, magnesium, iron, cadmium, chromium and magnesium during the entire sampling period. Whereas, no significant seasonal variation (p > 0.05) was observed in pH, EC, TDS, DO, BOD, residual chlorine, COD, oil and grease, fluoride, potassium, zinc, copper, selenium, nickel, aluminum, boron, silica, temperature, salinity, cyanide and phenol. Water Quality Index revealed that 39.39% and 35.29% samples belong to poor water quality category in premonsoon and monsoon, respectively. As per Heavy Metal Pollution Index, Degree of Contamination (Cd) and Heavy metal evaluation index, medium degree of pollution were exhibited by 51.52%, 30.30% and 45.45% samples in premonsoon and 20.59%, 35.29% and 26.47% samples in monsoon. Whereas, 5.88%, 2.94% and 5.88% samples were having high degree of pollution in monsoon and 15.15% samples caused high degree of pollution with respect to Cd in premonsoon. However, EC, Na%, PI, SAR and RSC values suggested that the water can be used for irrigation. Water type of the region had been found to be Ca–Mg–Cl–SO4 by Piper diagram.

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Based on FPGA Intelligent Physiological Parameters Acquisition

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.344.107 ◽

2013 ◽

Vol 344 ◽

pp. 107-110

Author(s):

Shun Ren Hu ◽

Ya Chen Gan ◽

Ming Bao ◽

Jing Wei Wang

Keyword(s):

High Speed ◽

Low Cost ◽

Physiological Parameters ◽

Sensor Data ◽

Low Power Consumption ◽

Physiological Signal ◽

Pulse Sensor ◽

Monitoring Applications ◽

Field Programmable ◽

Design Ideas

For the physiological signal monitoring applications, as a micro-controller based on field programmable gate array (FPGA) physiological parameters intelligent acquisition system is given, which has the advantages of low cost, high speed, low power consumption. FPGA is responsible for the completion of pulse sensor, the temperature sensor, acceleration sensor data acquisition and serial output and so on. Focuses on the design ideas and architecture of the various subsystems of the whole system, gives the internal FPGA circuit diagram of the entire system. The whole system is easy to implement and has a very good promotional value.

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Removing W Polymer Residue from BEOL Structures Using DSP+ (Dilute Sulfuric-Peroxide-HF) Mixture – A Case Study

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.195.128 ◽

2012 ◽

Vol 195 ◽

pp. 128-131 ◽

Cited By ~ 1

Author(s):

Hun Hee Lee ◽

Min Sang Yun ◽

Hyun Wook Lee ◽

Jin Goo Park

Keyword(s):

High Speed ◽

Semiconductor Device ◽

Environmental Issues ◽

Low Power Consumption ◽

Device Performance ◽

Metal Gate ◽

Feature Size ◽

High K ◽

Removal Of Metal

As the feature size of semiconductor device shrinks continuously, various high-K metals for 3-D structures have been applied to improve the device performance, such as high speed and low power consumption. Metal gate fabrication requires the removal of metal and polymer residues after etching process without causing any undesired etching and corrosion of metals. The conventional sulfuric-peroxide mixture (SPM) has many disadvantages like the corrosion of metals, environmental issues etc., DSP+(dilute sulfuric-peroxide-HF mixture) chemical is currently used for the removal of post etch residues on device surface, to replace the conventional SPM cleaning [. Due to the increased usage of metal gate in devices in recent times, the application of DSP+chemicals for cleaning processes also increases [.

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Study on Schottky Diode Characteristics Improving by X-Ray Irradiation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.717.113 ◽

2013 ◽

Vol 717 ◽

pp. 113-116

Author(s):

Sani Klinsanit ◽

Itsara Srithanachai ◽

Surada Ueamanapong ◽

Sunya Khunkhao ◽

Budsara Nararug ◽

...

Keyword(s):

Leakage Current ◽

Schottky Diode ◽

Room Temperature ◽

The Other ◽

Low Power Consumption ◽

Initial Value ◽

X Ray ◽

Forward Current ◽

Current Voltage ◽

Current Voltage Characteristics

The effect of soft X-ray irradiation to the Schottky diode properties was analyzed in this paper. The built-in voltage, leakage current, and work function of Schottky diode were investigated. The current-voltage characteristics of the Schottky diode are measured at room temperature. After irradiation at 70 keV for 55 seconds the forward current and leakage current are increase slightly. On the other hand, the built-in voltage is decrease from the initial value about 0.12 V. Consequently, this method can cause the Schottky diode has low power consumption. The results show that soft X-ray can improve the characteristics of Schottky diode.

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