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991.
A two-dimensional numerical simulation including a new interface state generation model has been developed to study the performance variation of a LDD MOSFET after a dc voltage stress. The spatial distribution of hot carrier induced interface states is calculated with a breaking silicon-hydrogen bond model. Mobility degradation and reduction of conduction charge due to interface traps are considered. A 0.6 μm LDD MOSFET was fabricated. The drain current degradation and the substrate current variation after a stress were characterized to compare the simulation. A reduction of the substrate current at Vg ≃0.5 Vd in a stressed device was observed from both the measurement and the simulation. Our study reveals that the reduction is attributed to a distance between a maximum channel electric field and generated interface states  相似文献   
992.
A continued fast interface trap generation is observed in n-channel MOS transistors after termination of the hot-carrier stress. The magnitude of this post-stress effect is strongly dependent on the conditions of the preceding stress, on the post-stress conditions and on the process parameters. For measurements at 293 K, a simple model is proposed which is based on the release of hydrogen by the thermal detrapping of holes, and which can explain the observed dependencies. The importance of the post-stress Dit-generation is illustrated for the case of dynamic stress conditions where it can lead to an apparently deviating degradation behavior  相似文献   
993.
Dielectric measurements using a rational function model   总被引:3,自引:0,他引:3  
A recently proposed rational function model for the aperture admittance of 50 ohm Teflon filled coaxial lines in contact with a homogeneous dielectric is experimentally validated. A calibration technique of the automatic network analyzer utilizing standard terminations and time domain gating is used. Uncertainties in the dielectric properties of reference liquids do not enter the calibration procedure. Experimental results for water and methanol are compared with estimated values. A model expression for the sensitivity of the probe is validated. The sensitivities of two coaxial line probes for the measurements made are determined. Results obtained using the new model are compared with those of other workers  相似文献   
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995.
An employee's failure to differentiate himself or herself from the perceived attitudes of another is at the heart of much stress in organizations. The world of family systems psychology identifies a dysfunctional process, called psychological fusion, which stems from insufficient self-definition by an individual and results in a dependency upon others to meet an innate need to feel accepted. People suffering from psychological fusion perceive any criticism as a threat, making it impossible for them to receive the critical feedback that is necessary for growth. To experience intrinsic motivation, people require a sense of relative self-determination and competence. This paper argues that much as employers take an interest in such emotional health issues as substance abuse and stress, they should also address psychological fusion; the paper offers methods for dealing with this interpersonal communications issue  相似文献   
996.
The paper examines collaborative writing practices students in the Air Force Institute of Technology's Graduate School of Logistics and Acquisition Management use to produce team-authored theses. In analyzing how student writing teams plan, execute, and assess writing activities, the researchers identify and describe some of the forms that collaboration takes, thereby successfully connecting their work within a broader research continuum concerning collaborative writing, particularly when applied in academic settings  相似文献   
997.
Examines several aspects of communication methods (`vehicles') and the various types of progress that have been made over the years. Much of the progress we have made in communicating is rooted strongly in our past. Much of the future of our communication vehicles will be rooted in our present and our understanding of our present. In this paper, we focus our discussion on six aspects of communication: (1) communication vehicles for teaching and learning; (2) forums for communication-wide interchange of ideas; (3) vehicles for search-and-retrieval of information; (4) the richness of the communication media set; (5) venues of communication-where we communicate and the tools we use; and (6) the idea of linearity in communication  相似文献   
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