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Lanthanum oxide (La2O3) nanostructured films are synthesized on a p-type silicon wafer by ablation of La2O3 pellet due to interaction with hot dense argon plasmas in a modified dense plasma focus (DPF) device. The nanostructured films are investigated using scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD) spectra. SEM study shows the formation of nano-films having nano-size structures with the average nanostructures size ~25, ~53, and ~45 nm for one, two, and three DPF shots, respectively. The nanostructures sizes and morphology of nano-films are consistent between the AFM and SEM analyses. XRD spectra confirms nano-sized La2O3 with an average grain size ~34, ~51, and ~42 nm for one, two, and three DPF shots, respectively. The electrical properties such as current-voltage and capacitance-voltage (C-V) characteristics of the Al-La2O3-Si metal-oxide- semiconductor (MOS) capacitor structure are measured. The current conduction mechanism of the MOS capacitors is also demonstrated. The C-V characteristics are further used to obtain the electrical parameters such as the dielectric constant, oxide thickness, flat-band capacitance, and flat-band voltage of the MOS capacitors. These measurements demonstrate significantly lower leakage currents without any commonly used annealing or doping, thereby revealing a significant improvement of the MOS nanoelectronic device performance due to the incorporation of the DPF-produced La2O3 nano-films.

Luminescent ZnO nanoparticles have been synthesized on silicon and quartz substrates under extremely non-equilibrium conditions of energetic ion condensation during the post-focus phase in a dense plasma focus (DPF) device. Ar+, O+, Zn+ and ZnO+ ions are generated as a result of interaction of hot and dense argon plasma focus with the surfaces of ZnO pellets placed at the anode. It is found that the sizes, structural and photoluminescence (PL) properties of the ZnO nanoparticles appear to be quite different on Si(1 0 0) and quartz substrates. The results of x-ray diffractometry and atomic force microscopy show that the ZnO nanoparticles are crystalline and range in size from 5-7 nm on Si(1 0 0) substrates to 10-38 nm on quartz substrates. Room-temperature PL studies reveal strong peaks related to excitonic bands and defects for the ZnO nanoparticles deposited on Si (1 0 0), whereas the excitonic bands are not excited in the quartz substrate case. Raman studies indicate the presence of E2 (high) mode for ZnO nanoparticles deposited on Si(1 0 0).

Information technology (IT) adoption research recognizes theoretical limitations in discerning if and when user behavior results from perceived external influences or from personal volition. A clear understanding of this issue requires a precise distinction between mandatory and volitional behaviors. Consistent with organismic integration theory (OIT), this study situates the locus of user motivations inside the user. Drawing upon an endogenous view of behaviors, this research makes three key contributions. First, it develops the theoretical basis for clearly discerning if and when behavior results from perceived external influences or from personal volition. Specifically, it examines how endogenous psychological feelings of autonomy, freedom, conflict, and external pressure can predict and explain user intentions. Second, it proposes that behavior may result from combinations of perceived external influences and personal volition. Recognizing how such "collections of motivations" together influence behavior advances our understanding beyond the "dichotomy" of extrinsic versus intrinsic motivations often adopted in prior research. Third, it proposes that some desired behaviors may be thwarted or impeded by a conflict between perceived external influences and personal volition. The theoretically grounded research model was empirically validated in a field study on Blackboard, a Web-based education platform at a large university. Data collected from a sample of 211 users were tested using structural equation models of initial system adoption and experienced use. Empirical support was found for the proposed model and related hypotheses. The results of this study advance our understanding about user motivations for adopting IT. © 2008 M.E. Sharpe, Inc.

In recent years, several organizations have implemented nonmandatory information and communication systems that escape the conventional behavioral logic of understanding acceptance and usage from a normative perspective of compliance with the beliefs of others. Because voluntary systems require users' volitional behavior, researchers have traced recent implementation failures to a lack of user commitment. However, gaps in our understanding of volitional usage behavior and user commitment have made it difficult to advance theory, research, and practice on this issue. To validate a proposed research model, cross-sectional, between-subjects, and within-subjects field data were collected from 714 users at the time of initial adoption and after six months of extended use. The model explained between 44.1 percent and 58.5 percent of the variance in adoption and usage behavior based upon direct effects of user commitment. Findings suggest that user commitment plays a critical role in the volitional acceptance and usage of such systems. Affective commitment - that is, internalization and identification based upon personal norms - exhibits a sustained positive influence on usage behavior. In contrast, continuance commitment - that is, compliance based upon social norms - shows a sustained negative influence from initial adoption to extended use. Theory development based upon Kelman's social influence framework offers new empirical insights about system users' commitment and how it affects volitional usage behavior. © 2005 M.E. Sharpe, Inc.

User's commitment to the success of information technology (IT) systems is discussed. IT practitioners are demonstrating the increased awareness of the importance of user behavioral issues to business performance. The productivity of IT at macro-level is dependent on the commitment of users. User commitment and motivation are critical not only for adoption of new information and communication technologies but also for their sustained use.