Domain behavior in lead zirconate titanate (PZT) thin film capacitors

Abstract

Domain behavior based on surface energy and volumetric free energy was discussed in relation to imprint. Surface enery and volumetric free energy result in net free energy, which determines the critical size for domain growth. If a domain size is greater than the critical size, they will grow spontaneously under a constant electric field or even under zero electric field. Sometimes, they can grow to the extent that they dominate reverse domains. This phenomenon appears to be polarization reversal under zero voltage bias. Spontaneous domain growth either under zero electric field or a constant electric field was demonstratred. This phenomenon can be partly a source of asymmetric imprint mechanism.     

PZT capacitors using IrO2 electrode by RF magnetron sputtering

Abstract

RF magnetron sputtered Pb(Zr_x, Ti_1-x)O₃ [PZT] films were prepared on IrO₂/SiO₂/Si and Pt/IrO₂/SiO₂/Si substrates using the ceramic PZT target with Pb_1.1(Zr_0.52Ti_0.48)O₃ composition. In order to obtain single perovskite phase, PZT film was sputtered at room temperature under Ar plasma and followed by high temperature annealing under oxygen atmosphere. In case of Pt/PZT/IrO₂ capacitor, Δ P (=P*-P∧) was decreased with oxygen annealing temperature. However, it was increased in Pt/PZT/Pt/IrO₂ capacitor. Leakage current density of Pt/PZT/Pt/IrO₂ capacitor, which was used for improving leakage characteristics, was about 10^-2A/cm^?2 order lower than that of Pt/PZT/IrO₂ capacitor. Leakage current density of Pt/PZT/Pt/IrO₂ capacitor annealed at 700°C was 6.6x10^-6A/cm². From the fatigue test, Pt/PZT/IrO₂ capacitor annealed at 650°C and Pt/PZT/Pt/IrO₂ capacitor annealed at 700°C showed 3% and 12% degradation of Δ P after 5×10¹⁰ fatigue cycles, respectively.     

Operation of 1550-nm electroabsorption-Modulated laser at 40/spl deg/C for 10-gb/s, 40-km transmission

Semicooled operation at 40/spl deg/C of electroabsorptive modulator integrated laser (EML) for intermediate reach communication has been demonstrated. Reproducible operation at the elevated temperature was achieved through a device parameter optimized based on the temperature dependence of the dc characteristics of EML and a design of multi-quantum-well structure providing both relevant output power and high-frequency bandwidth at 40/spl deg/C. Good eye pattern and near zero chirp with the average power over 0 dBm are obtained at 40/spl deg/C, with an estimated lifetime over 20 years.     

Modeling the benefit of e-recruiting process integration

While e-recruiting has been widely adopted as one of the most successful e-business applications, it constitutes an under-researched area in e-business research. This study reviews the integration issues in e-recruiting and presents an e-recruiting integration decision model. The benefits of the investment in e-recruiting process integration are discussed in comparison to separate e-recruiting investments. We show that the optimal investment in the e-recruiting process integration results in a lower total cost than the separate e-recruiting investments. In addition, in light of the widely practiced resource constrained investments, we present the method of Lagrange multipliers which is used to find the optimal investment under a budget constraint.     

Perceptual grouping of line features in 3-D space: a model-based framework

In this paper, we propose a novel model-based perceptual grouping algorithm for the line features of 3-D polyhedral objects. Given a 3-D polyhedral model, perceptual grouping is performed to extract a set of 3-D line segments which are geometrically consistent with the 3-D model. Unlike the conventional approaches, grouping is done in 3-D space in a model-based framework. In our unique approach, a decision tree classifier is employed for encoding and retrieving the geometric information of the 3-D model. A Gestalt graph is constructed by classifying input instances into proper Gestalt relations using the decision tree. The Gestalt graph is then decomposed into a few subgraphs, yielding appropriate groups of features. As an application, we suggest a 3-D object recognition system which can be accomplished by selecting a best-matched group. In order to evaluate the performance of the proposed algorithm, experiments are carried out on both synthetic and real scenes.     

Text information extraction in images and video: a survey

Text data present in images and video contain useful information for automatic annotation, indexing, and structuring of images. Extraction of this information involves detection, localization, tracking, extraction, enhancement, and recognition of the text from a given image. However, variations of text due to differences in size, style, orientation, and alignment, as well as low image contrast and complex background make the problem of automatic text extraction extremely challenging. While comprehensive surveys of related problems such as face detection, document analysis, and image & video indexing can be found, the problem of text information extraction is not well surveyed. A large number of techniques have been proposed to address this problem, and the purpose of this paper is to classify and review these algorithms, discuss benchmark data and performance evaluation, and to point out promising directions for future research.     

Almost rotation-minimizing rational parametrization of canal surfaces

Almost rotation minimizing parametrization of the canal surface is given. The basic building block of our approach is the curve approximation scheme that enables us to construct a curve, called the parameter curve, on the canal surface that produces, when projected and rescaled, an almost parallel normal vector field on the spine curve. Its construction relies on our earlier methods and results on relating the geometry of the canal surface to the Lorentzian geometry of the Minkowski geometry via the Clifford algebra formalism. We then iteratively construct patches out of the parameter curves via suitable interpolation procedure. Furthermore, its rotational deviation, i.e., the angle deviation from the parallel (no rotation) frame along the spine curve, can be controlled with the use of the rotation deviation estimate of the parameter curves. Our numerical experiment shows that the rotation deviation is minuscule. When compared with other earlier results including our earlier one, our result fares extremely favorably. To facilitate the implement, a practitioners' summary is given in the appendix.     

Introducing UniCorT: an iterative university course timetabling tool with MaxSAT

Journal of Scheduling - This paper describes the UniCorT tool designed to solve university course timetabling problems specifically tailored for the 2019 International Timetabling Competition (ITC...     

Using WinWin Quality Requirements Management Tools: A Case Study

Negotiating stakeholder WinWin relationships among software quality requirements is a technique that emerged during the 1990's in order to overcome the difficulties arising from contract-oriented specification compliance (popular in the 1970's) and service-oriented customer satisfaction (popular in the 1980's). Obstacles to adoption of negotiated win-win relationships include coordination of multiple stakeholder interests and priorities, reasoning of complicated dependencies, and scalability of an exponentially increasing resolution option space. Conflict identification and resolution techniques are key success factors to overcome the obstacles. This paper describes two exploratory knowledge-based tools (called QARCC and S-COST)^* for conflict identification and resolution and how they were used in the digital library projects of a USC Software Engineering class during the 1996/97 school year. A comparative analysis with the artifacts surfaced by stakeholders and the artifacts generated and analyzed by QARCC and S-COST focused on the conflict resolution process, stakeholders' roles and their relationships to quality artifacts, and tool effectiveness. We conclude that the tools helped stakeholders: (1) surface and negotiate conflicts; (2) identify conflicts among functional and quality requirements; and (3) generate, visualize, and negotiate potential resolution options for the conflicts.