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11.
In this work, we present the results of dielectric relaxation and defect generation kinetics towards reliability assessments for Zr-based high-k gate dielectrics on p-Ge (1 0 0). Zirconium tetratert butoxide (ZTB) was used as an organometallic source for the deposition of ultra thin (∼14 nm) ZrO2 films on p-Ge (1 0 0) substrates. It is observed that the presence of an ultra thin lossy GeOx interfacial layer between the deposited high-k film and the substrate, results in frequency dependent capacitance-voltage (C-V) characteristics and a high interface state density (∼1012 cm−2 eV−1). Use of nitrogen engineering to convert the lossy GeOx interfacial layer to its oxynitride is found to improve the electrical properties. Magnetic resonance studies have been performed to study the chemical nature of electrically active defects responsible for trapping and reliability concerns in high-k/Ge systems. The effect of transient response and dielectric relaxation in nitridation processes has been investigated under high voltage pulse stressing. The stress-induced trap charge density and its spatial distribution are reported. Charge trapping/detrapping of stacked layers under dynamic current stresses was studied under different fluences (−10 mA cm−2 to −50 mA cm−2). Charge trapping characteristics of MIS structures (Al/ZrO2/GeOx/Ge and Al/ZrO2/GeOxNy/Ge) have been investigated by applying pulsed unipolar (peak value - 10 V) stress having 50% duty-cycle square voltage wave (1 Hz-10 kHz) to the gate electrode. 相似文献
12.
Singh N. Agarwal A. Bera L.K. Liow T.Y. Yang R. Rustagi S.C. Tung C.H. Kumar R. Lo G.Q. Balasubramanian N. Kwong D.-L. 《Electron Device Letters, IEEE》2006,27(5):383-386
This paper demonstrates gate-all-around (GAA) n- and p-FETs on a silicon-on-insulator with /spl les/ 5-nm-diameter laterally formed Si nanowire channel. Alternating phase shift mask lithography and self-limiting oxidation techniques were utilized to form 140- to 1000-nm-long nanowires, followed by FET fabrication. The devices exhibit excellent electrostatic control, e.g., near ideal subthreshold slope (/spl sim/ 63 mV/dec), low drain-induced barrier lowering (/spl sim/ 10 mV/V), and with I/sub ON//I/sub OFF/ ratio of /spl sim/10/sup 6/. High drive currents of /spl sim/ 1.5 and /spl sim/1.0 mA//spl mu/m were achieved for 180-nm-long nand p-FETs, respectively. It is verified that the threshold voltage of GAA FETs is independent of substrate bias due to the complete electrostatic shielding of the channel body. 相似文献
13.
Shailendra Singh Subhash Chandra Bera Punam Pradeep Kumar Dhaval Pujara 《Radioelectronics and Communications Systems》2017,60(11):479-484
In this paper, formulae to determine the lowest order and other higher order spurious frequencies that coincide with desired output signal frequencies of mixers have been derived. The proposed formulae give general expressions that are suitable for any order of heterodyne mixing. The formulae have been verified using a suitable example and compared with the simulation results obtained through the radio frequency simulation software of Advanced Design System. The formulae directly reveal the order of the troublesome spurious frequencies that the designers would encounter in heterodyne systems. In comparison with these direct formulae, the results of existing spurious analysis software are based on the maximum order of simulation carried out. Based on these simulations, the coinciding spurious components have to be manually sorted out. Proposed formulae are quick tools used by the microwave system and circuit designers for choosing and finalizing heterodyne frequencies in their designs without the need for any simulations. 相似文献
14.
The trapping/detrapping behavior of charge carriers in ultrathin SiO2/TiO2 stacked gate dielectric during constant current (CCS) and voltage stressing (CVS) has been investigated. Titanium tetrakis iso-propoxides (TTIP) was used as the organometallic source for the deposition of ultra-thin TiO2 films at low temperature (<200 °C) on strained-Si/relaxed-Si0.8Ge0.2 heterolayers by plasma-enhanced chemical vapor deposition (PECVD) in a microwave (700 W, 2.45 GHz) plasma cavity discharge system at a pressure of 66.67 Pa. Stress-induced leakage current (SILC) through SiO2/TiO2 stacked gate dielectric is modeled by taking into account the inelastic trap-assisted tunneling (ITAT) mechanism via traps located below the conduction band of TiO2 layer. The increase in the gate current density observed during CVS from room temperature up to 125 oC has been analyzed and modeled considering both the buildup of charges in the layer as well as the SILC contribution. Trap generation rate and trap cross-section are extracted. A capture cross-section in the range of 10−19 cm2 as compared to 10−16 cm2 in SiO2 has been observed. A temperature-dependent trap generation rate and defects have also been investigated using time-dependent current density variation during CVS. The time dependence of defect density variation is calculated within the dispersive transport model, assuming that these defects are produced during random hopping transport of positively charge species in the insulating high-k stacked layers. SILC generation kinetics, i.e. defect generation probability under different injected fluences for various high-constant stress voltages in both polarities have been studied. An empirical relation between trap generation probability and applied stress voltage for various injected fluences has been developed. 相似文献
15.
Oskar Rexfelt Lars Almefelt Daniel Zackrisson Teres Hallman Johan Malmqvist MariAnne Karlsson 《Research in Engineering Design》2011,22(3):153-171
This paper outlines the results of a project aiming to develop and apply methods for service co-creation with customers, focusing
on the early phases of service development. The project is collaboration between a manufacturing firm in the automotive industry,
one of their B2B-customers (a transportation firm), as well as a university, all in Sweden. The research team selected and
developed methods and work practices for problem analysis, idea generation, development and evaluation of services. Thus doing,
methodological influence was taken from the area of engineering design. The proposed approaches were applied in a service
development experiment mainly based on workshops. The experiment was followed up by an analysis of the resulting output, an
interview series, and an evaluation by peers in focus groups. The goal of this article is to answer the following research
questions: (1) What is the industrial applicability of co-creating services using a structured approach, e.g. what are the
benefits and challenges? (2) What do the different actors contribute with using this approach, and what possible factors influence
the nature and quality of the actors’ contributions? (3) Based on the answers to the questions above, what aspects should
be considered to support situated planning and execution of future service co-creation projects? A central conclusion is that
a structured approach is industrially applicable, but it is also evident that there is no completely universal recipe for
service innovation. Addressing these insights, the paper also contributes with guidelines to support the situation-adapted
set-up of future service co-creation projects. 相似文献
16.
Acquired immune deficiency syndrome is an epidemic infectious disease which is caused by the human immunodeficiency virus (HIV) and that has proliferated across worldwide. It has been a matter of concern for the scientific community to develop an antiretroviral therapy, which will prompt a rapid decline in viral abundance. With this motivation, this study proposes the design of a robust super twisting sliding mode controller based on output information for an uncertain HIV infection model. The control objective is to decrease the concentration of infected CD4+ T cells to a specified level by drug administration using only the output information of the uncertain HIV infection model which is total CD4+ T cell concentration. The robust output‐feedback controller has been developed in combination with a robust exact differentiator, functioning as an observer. The reported analysis demonstrates that the approach proposed here is capable of ensuring robust performance under several operating conditions, measurement and modelling error, parametric uncertainties and external disturbances and the simulation results prove the proficiency of the controller proposed.Inspec keywords: control system synthesis, observers, robust control, drugs, medical control systems, diseases, uncertain systems, variable structure systems, patient treatment, feedback, cellular biophysics, microorganismsOther keywords: robust control, antiretroviral therapy, sliding mode control approach, acquired immune deficiency syndrome, epidemic infectious disease, human immunodeficiency virus, scientific community, robust super, mode controller, output information, uncertain HIV infection model, control objective, infected CD4, total CD4, T cell concentration, robust output‐feedback controller, robust exact differentiator, robust performance 相似文献
17.
Pawe Mieszczaski Szmon Januszyk Nikola Zmarzy Piotr Ossowski Konrad Dziobek Dorota Sagan Dariusz Boro Marcin Opawski Beniamin Oskar Grabarek 《International journal of molecular sciences》2022,23(24)
Reactive oxygen species are formed as by-products of normal cell metabolism. They are needed to maintain cell homeostasis and signaling, which is possible due to defense systems. Disruption of this balance leads to oxidative stress that can induce cancer. Redox regulation by miRNAs may be a potential therapeutic target. The aim of the study was to assess the activity of genes associated with oxidative stress in endometrial cancer and to determine their relationship with miRNAs. The study included 45 patients with endometrioid endometrial cancer and 45 without neoplastic changes. The expression profile of genes associated with oxidative stress was determined with mRNA microarrays, RT-qPCR and ELISA. The miRNA prediction was performed based on the miRNA microarray experiment and the mirDB tool. PRDX2 and AQP1 showed overexpression that was probably not related to miRNA activity. A high level of PKD2 may be the result of a decrease in the activity of miR-195-3p, miR-20a, miR-134. A SOD3 level reduction can be caused by miR-328, miR-363. In addition, miR-363 can also regulate KLF2 expression. In the course of endometrial cancer, the phenomenon of oxidative stress is observed, the regulation of which may be influenced by miRNAs. 相似文献
18.
Abhinandan Rana Madhusudan Bera Durga Sankar Chowdhuri Debdoot Hazari Swapan Kumar Jana Ennio Zangrando Sudipta Dalai 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(2):360-368
Abstract
A new 3D silver complex [Ag(mela)(H2O)(NO3)]n (1) (mela = melamine or 2,4,6-triaminotriazine) is synthesized and characterized by single crystal X-ray diffraction, IR, and elemental analysis. The structural characterization shows that the compound crystallizes in space group C c, a = 8.181(2), b = 10.269(3) c = 11.347(3) ?, β = 105.88(2)°, Z = 4. Out of several structurally characterized transition metal compounds comprising melamine, the titled complex represents a rare example of μ 3 -melamine coordination mode realized through the heterocycle nitrogen donors. The fluorescent property of complex 1 was investigated and the mechanism was validated by means of a density functional theory (DFT) calculation. 相似文献19.
Ceria-supported Au catalyst has been synthesized by the solution combustion method for the first time and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Au is dispersed as Au0 as well as Au3+ states on CeO2 surface of 20-30 nm crystallites. On heating the as-prepared 1% Au/CeO2 in air, the concentration of Au3+ ions on CeO2 increases at the expense of Au0. Catalytic activities for CO and hydrocarbon oxidation and NO reduction over the as-prepared and the heat-treated 1% Au/CeO2 have been carried out using a temperature-programmed reaction technique in a packed bed tubular reactor. The results are compared with nano-sized Au metal particles dispersed on -Al2O2 substrate prepared by the same method. All the reactions over heat-treated Au/CeO2 occur at lower temperature in comparison with the as-prepared Au/CeO2 and Au/Al2O2. The rate of NO + CO reaction over as-prepared and heat-treated 1% Au/CeO2 are 28.3 and 54.0 mol g-1 s-1 at 250 and 300 °C respectively. Activation energy (E
a) values are 106 and 90 kJ mol-1 for CO + O2 reaction respectively over as-prepared and heat-treated 1% Au/CeO2 respectively. 相似文献
20.
Dipta Mukherjee Arjun Dey A. Carmel Mary Esther Debajyoti Palai N. Sridhara Parthasarathi Bera Manjima Bhattacharya A. Rajendra Anand Kumar Sharma Anoop Kumar Mukhopadhyay 《Ceramics International》2018,44(8):8913-8921
Smooth, uniform and crystalline vanadium oxide thin films were deposited on quartz by spin coating technique with four different rpm i.e., 1000, 2000, 3000 and 4000 and subsequently post annealed at 350, 450 and 550?°C in vacuum. Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) techniques were utilized for microstructural characterizations and phase analysis, respectively, for vanadium oxide powder and deposited film. Nanorods were observed to be grown after vacuum annealing. X-ray photoelectron spectroscopy (XPS) technique was utilized to study the elemental oxidation state of deposited vanadium oxide films. Thermo-optical and electrical properties such as solar transmittance (τs), reflectance (ρs), absorptance (αs), infrared (IR) emittance (εir) and sheet resistance (Rs) of different thin films were evaluated. Based on the optical characteristics the optimized condition of the film processing was identified to be spin coated at 3000?rpm. Subsequently, the nanoindentation technique was utilized to measure hardness and Young's modulus of the optimized film. The measured nanomechanical properties were found to be superior to those reported for sputtered vanadium oxide films. Finally, temperature dependent phase transition characteristics of optimized vanadium oxide films were studied by differential scanning calorimetry (DSC) technique. Reversible and repeatable phase transition was found to occur in the range of 44–48?°C which was significantly lower than the phase transition temperature (i.e., 68?°C) of bulk VO2. 相似文献