Zn1-xTex Ovonic Threshold Switching Device Performance and its Correlation to Material Parameters

We have experimentally demonstrated a strong correlation between the electrical properties of Zn1-xTex Ovonic threshold switching (OTS) selector device and the material properties analysed by X-ray diffraction (XRD), spectroscopic ellipsometry, and X-ray photoelectron spectroscopy (XPS). The correlation and the key material parameters determining the device performances were investigated. By comparing the experimental data with the calculation results from various analytical models previously developed for OTS materials, the electrical properties of the device were shown to be dependent on the key material parameters; the concentration of sub-gap trap states and the bandgap energy of the OTS material. This study also experimentally demonstrated that those key parameters have determined the device performance as expected from the analytical model. The origin of the OTS phenomenon and conduction mechanism were explained both experimentally and theoretically. This leads to better understanding of the conduction mechanism of OTS devices, and an insight for process improvement to optimize device performance for selector application.11Ysciescopu

Tunnel Barrier Engineering of Titanium Oxide for High Non-Linearity of Selector-less Resistive Random Access Memory

In this study, the effect of the oxygen profile and thickness of multiple-layers TiOx on tunnel barrier characteristics was investigated to achieve high non-linearity in low-resistance state current (I-LRS). To form the tunnel barrier in multiple-layer of TiOx, tunnel barrier engineering in terms of the thickness and oxygen profile was attempted using deposition and thermal oxidation times. It modified the defect distribution of the tunnel barrier for effective suppression of ILRS at off-state (1/2V(Read)). By inserting modified tunnel barrier in resistive random access memory, a high non-linear I-LRS was exhibited with a significantly lowered I-LRS for 1/2V(Read). (C) 2014 AIP Publishing LLC.ope

THE RELATIONAL STRUCTURE OF MULTI-VENDOR OUTSOURCING: ITS IMPACT ON ORGANIZATIONAL LEARNING

The increasing trend of engaging multiple vendors, coupled with the concern for “possible” loss of knowledge in outsourcing relationship, compels us to investigate organizational learning in multi-vendor outsourcing from a social relation perspective. The nature of social relation has been conceptualized in terms of how organizational relationships with social entities facilitate and/or inhibit organizational learning. In particular, we examine how two different relational structures – single vendor dominant model and multi-vendor dominant model – are associated with the two types of organizational learning – exploitative and exploratory learning. Furthermore, this study tries to investigate how three critical dimensions – structural (core vs. non-core functions), affective (partnership vs. transaction) and cognitive (business value vs. IT capability) - in social relations affect the relationships between the two relational structures and the two types of organizational learning in the context of IT outsourcing. The proposed hypotheses will be empirically tested via questionnaires in a field-study. This study attempts to shed light on how clients can better engage in exploitative and exploratory learning to reap the benefits of multi-vendor outsourcing approach

Dual functionality of threshold and multilevel resistive switching characteristics in nanoscale HfO2-based RRAM devices for artificial neuron and synapse elements

We demonstrate the dependency of dual functionality on the operating current with threshold and multilevel switching behaviors in HfO2-based resistive memory (RRAM) devices. These devices can be used to produce electronic neurons and synapses for neuromorphic computing applications. The control of the formation and rupture of a conductive filament (CF) driven by the movement of oxygen vacancies (V-0) in a high-current (100 mu A) operated RRAM acting as synapse enables multilevel conductance states to be achieved. On the other hand, operation of the device in the low-current regime (<= 10 mu A) leads to a transition from-memory to threshold switching, which is activated only by applying voltage. This behavior is described by a weak CF composed of a few V0 created by using a Poole-Frenkel based analytical model. Thus, threshold switching in RRAM operated at a low current plays a role in generating output spikes as neurons when the accumulated inputs exceed the critical value. (C) 2017 Elsevier B.V. All rights.reserved.113Nsciescopu

Simple Binary Ovonic Threshold Switching Material SiTe and Its Excellent Selector Performance for High-Density Memory Array Application

In this letter, simple binary Ovonic threshold switching (OTS) material with outstanding selector device performance has been demonstrated. Even with its simple material composition and easy fabrication process, the selector device with the binary OTS material showed excellent selector performance such as high-OFF resistance (> 1 G Omega at 0.1 V), low-ON resistance ( 10 8 cyclesof 150 ns pulse), high electrical stability (> 1ks at 1.2 V), and high thermal stability (> 400 degrees C /30 min). Furthermore, conduction mechanism of the OTS has been explained by Poole-Frenkel-based analytical modeling.116Nsciescopu

Holistic Archetypes of IT Outsourcing Strategy: A Contingency Fit and Configurational Approach

The goal of this paper is to determine holistic archetypes of information technology (IT) outsourcing strategy. It does this through an overarching theoretical framework that integrates three dominant theories of interorganizational relations in the IT outsourcing literature, namely transaction cost economics, resource dependency, and social exchange theories. A contingency fit theoretical framing is married to a configurational approach to explicate the intricate relationships that spring up between a focal firm and its outsourcing vendors when they are working toward specific strategic objectives under varying contingencies. In line with this theoretical objective, we used qualitative comparative analysis (QCA), a set-theoretic configuration method that can handle the interdependent complexity among multiple elements of IT outsourcing. The technique was applied to a sample of 235 companies that have outsourced some or all of their IT functions. Findings at the project level of analysis empirically reveal two sets of configurations of strategic IT outsourcing elements, one set of configurations resulting in high economic benefit and the other set leading to high strategic benefit. Next, we compare similarities and differences among multiple, equifinal configurations and infer archetypes of IT outsourcing strategy internally congruent in terms of the strategic objectives as well as matching specific contextual contingencies. Our holistic archetypes take the form of theoretical propositions integrating the previous fragmented and inconsistent knowledge in IT outsourcing resulting from the causal ambiguity and complexity inherent in IT outsourcing projects as well as from divergent theories in the literature. Furthermore, by defining specific contingency boundaries, our archetypes provide managers with context-specific guidelines for strategic decisions regarding their relationships with outsourcing vendors, helping different sized firms to effectively succeed in IT outsourcing, contingent on the IT type being outsourced. Finally, we discuss new insights and implications of this study for complementing and extending the extant theories in IT outsourcing