Showing papers by "David P. Norton published in 2006"

Alignment: Using the Balanced Scorecard to Create Corporate Synergies

Abstract: Most organizations consist of multiple business and support units, each populated by highly trained, experienced executives But often the efforts of individual units are not coordinated, resulting in conflicts, lost opportunities, and diminished performance Robert S Kaplan and David P Norton argue that the responsibility for this critical alignment lies with corporate headquarters In this book, the authors apply their revolutionary Balanced Scorecard management system to corporate-level strategy, revealing how highly successful enterprises achieve powerful synergies by explicitly defining corporate headquarters' role in setting, coordinating, and overseeing organizational strategy Based on extensive field research in organizations worldwide, Alignment shows how companies can build an enterprise-level Strategy Map and Balanced Scorecard that clearly articulate the "enterprise value proposition": how the enterprise creates value above that achieved by individual business units operating alone The book provides case studies, actionable frameworks, and sample scorecards that show how to align business and support units, boards of directors, and external partners with the corporate strategy and create a governance process that will ensure that alignment is sustained The next breakthrough in strategy execution from the field's premier thinkers, Alignment shows how today's companies can unlock unrealized value from enterprise synergies

How to implement a new strategy without disrupting your organization.

Abstract: Throughout most of modern busi ness history, corporations have attempted to unlock value by matching their structures to their strategies: Centralization by function. Decentralization by product category or geographic region. Matrix organizations that attempt both at once. Virtual organizations. Networked organizations. Velcro organizations. But none of these approaches has worked very well. Restructuring churn is expensive, and new structures often create new organizational problems that are as troublesome as the ones they try to solve. It takes time for employees to adapt to them, they create legacy systems that refuse to die, and a great deal of tacit knowledge gets lost in the process. Given the costs and difficulties involved in finding structural ways to unlock value, it's fair to raise the question: Is structural change the right tool for the job? The answer is usually no, Kaplan and Norton contend. It's far less disruptive to choose an organizational design that works without major conflicts and then design a customized strategic system to align that structure to the strategy. A management system based on the balanced scorecard framework is the best way to align strategy and structure, the authors suggest. Managers can use the tools of the framework to drive their unit's performance: strategy maps to define and communicate the company's value proposition and the scorecard to implement and monitor the strategy. In this article, the originators of the balanced scorecard describe how two hugely different organizations--DuPont and the Royal Canadian Mounted Police-used corporate scorecards and strategy maps organized around strategic themes to realize the enormous value that their portfolios of assets, people, and skills represented. As a result, they did not have to endure a painful series of changes that simply replaced one rigid structure with another.

Electroluminescence from ZnO nanowire/polymer composite p-n junction

Abstract: The characteristics of a hybrid p-n junction consisting of the hole-conducting polymer poly(3,4-ethylene-dioxythiophene)-poly(styrene-sulfonate) (PEDOT/PSS) and n-ZnO nanorods grown on an n-GaN layer on sapphire are reported. Spin coating of polystyrene was used to electrically isolate neighboring nanorods and a top layer of transparent conducting indium tin oxide (ITO) was used to contact the PEDOT/PSS. Multiple peaks are observed in the electroluminescence spectrum from the structure under forward bias, including ZnO band edge emission at ∼383nm as well as peaks at 430, 640, and 748nm. The threshold bias for UV light emission was <3V, corresponding to a current density of 6.08Acm−2 through the PEDOT/PSS at 3V.

Pediatrician characteristics associated with child abuse identification and reporting: results from a national survey of pediatricians.

Abstract: Pediatrician experience with child protective services (CPS) and factors associated with identifying and reporting suspected child physical abuse were examined by a survey of members of the American Academy of Pediatrics (AAP). Respondents provided information about their demographics and experience, attitudes and practices with child abuse. They indicated their diagnosis and management of a child in a purposely ambiguous clinical vignette. Pediatricians who had received recent child abuse education were more confident in their ability to identify and manage child abuse. High confidence in ability to manage child abuse and positive attitude about domestic violence screening and value of anticipatory guidance predicted that pediatricians would have high suspicion that the child in the vignette was abused and that they would report the child to CPS. Future efforts to improve medical intervention in child abuse should focus on physician attitudes and experience, as well as cognitive factors.

ZnO spintronics and nanowire devices

Abstract: ZnO is a very promising material for spintronics applications, with many groups reporting room-temperature ferromagnetism in films doped with transition metals during growth or by ion implantation. In films doped with Mn during pulsed laser deposition (PLD), we find an inverse correlation between magnetization and electron density as controlled by Sn-doping. The saturation magnetization and coercivity of the implanted single-phase films were both strong functions of the initial anneal temperature, suggesting that carrier concentration alone cannot account for the magnetic properties of ZnO:Mn and factors such as crystalline quality and residual defects play a role. Plausible mechanisms for ferromagnetism include the bound magnetic polaron model or exchange that is mediated by carriers in a spin-split impurity band derived from extended donor orbitals. The progress in ZnO nanowires is also reviewed. The large surface area of nanorods makes them attractive for gas and chemical sensing, and the ability to control their nucleation sites makes them candidates for microlasers or memory arrays. Single ZnO nanowire depletion-mode metal-oxide semiconductor field effect transistors exhibit good saturation behavior, threshold voltage of ∼−3 V, and a maximum transconductance of 0.3 mS/mm. Under ultraviolet (UV) illumination, the drain-source current increased by approximately a factor of 5 and the maximum transconductance was ∼5 mS/mm. The channel mobility is estimated to be ∼3 cm2/Vss, comparable to that for thin film ZnO enhancement mode metal-oxide semiconductor field effect transistors (MOSFETs), and the on/off ratio was ∼25 in the dark and ∼125 under UV illumination. The Pt Schottky diodes exhibit excellent ideality factors of 1.1 at 25°C, very low reverse currents, and a strong photoresponse, with only a minor component with long decay times thought to originate from surface states. In the temperature range from 25°C to 150°C, the resistivity of nanorods treated in H2 at 400°C prior to measurement showed an activation energy of 0.089 eV and was insensitive to ambient used. By contrast, the conductivity of nanorods not treated in H2 was sensitive to trace concentrations of gases in the measurement ambient even at room temperature, demonstrating their potential as gas sensors. Sensitive pH sensors using single ZnO nanowires have also been fabricated.

Band gap properties of Zn1−xCdxO alloys grown by molecular-beam epitaxy

Abstract: Optical absorption and reflectance measurements are performed to evaluate compositional and temperature dependences of band gap energies of Zn1−xCdxO alloys grown by molecular-beam epitaxy. The compositional dependence of the band gap energy, determined by taking into account excitonic contributions, is shown to follow the trend Eg(x) = 3.37−2.82x+0.95x2. Incorporation of Cd was also shown to somewhat slow down thermal variation of the band gap energies, beneficial for future device applications.

Wide Bandgap Semiconductor Nanorod and Thin Film Gas Sensors

Abstract: In this review we discuss the advances in use of GaN and ZnO-based solid-state sensors for gas sensing applications. AlGaN/GaN high electron mobility transistors (HEMTs) show a strong dependence of source/drain current on the piezoelectric polarization -induced two dimensional electron gas (2DEG). Furthermore, spontaneous and piezoelectric polarization induced surface and interface charges can be used to develop very sensitive but robust sensors for the detection of gases. Pt-gated GaN Schottky diodes and Sc2O3/AlGaN/GaN metal-oxide semiconductor diodes also show large change in forward currents upon exposure to H2 containing ambients. Of particular interest are methods for detecting ethylene (C2H4), which offers problems because of its strong double bonds and hence the difficulty in dissociating it at modest temperatures. ZnO nanorods offer large surface area, are bio-safe and offer excellent gas sensing characteristics.

Band-edge electroluminescence from N+-implanted bulk ZnO

Abstract: N+ ion implantation at moderate doses (1013–1014cm−2) into nominally undoped (n∼1017cm−3) bulk single-crystal ZnO substrates followed by annealing in the range 600–950°C was used to fabricate diodes that show visible luminescence at 300K and band-edge electroluminescence at 120K (∼390nm) under forward bias conditions. The current-voltage behavior of the diodes are characteristic of metal-insulator-semiconductor devices and suggest the implantation creates a more resistive region in the n‐ZnO in which holes are created by impact ionization during biasing, similar to the case of electroluminescence in ZnO varistors. The series resistance is only 25Ω due to the use of the conducting ZnO substrate.

Electrical properties of undoped bulk ZnO substrates

Abstract: Undoped bulk ZnO crystals obtained from Tokyo Denpa show either resistive behavior [(5×104)−(3×105) Ohm cm) or low n-type conductivity (n ⋍1014 cm−3) with mobilities in the latter case of 130–150 cm2/V sec. The variation in resistivity may be related to the thermal instability of Li that is present in the samples. The Fermi level is pinned by 90-meV shallow donors that are deeper than the 70 meV and hydrogen-related 35-meV shallow donors in Eagle Pitcher and Cermet substrates. In all three cases, 0.3-eV electron traps are very prominent, and in the Tokyo Denpa material they dominate the high-temperature capacitance-frequency characteristics. The concentration of these traps, on the order of 2×1015 cm−3, is about 20 times higher in the Tokyo Denpa ZnO compared to the two other materials. The other electron traps at Ec −0.2 eV commonly observed in undoped n-ZnO are not detected in conducting Tokyo Denpa ZnO samples, but they may be traps that pin the Fermi level in the more compensated high-resistivity samples.

System for hydrogen sensing

Abstract: Exemplary embodiments provide a self-powered wireless gas sensor system and a method for gas sensing using the system. The system can be used to detect and constantly track a presence of various gases including hydrogen, ozone and/or any hydrocarbon gas, and remotely transmit the sensing signal. The system can include a low power gas sensor that consumes less than about 30 nano-watts of power. As a result, the system can detect the presence of hydrogen at about 10 ppm. The sensor can also provide a fast response time of about 1-2 seconds. In various embodiments, the system can be physically small and packaged with all components assembled as a single compact unit.

A perspective on conducting oxide buffers for Cu-based YBCO-coated conductors

Abstract: The physical and electrical characteristics of oxide buffer layers for Cu-based coated conductors are reviewed, with emphasis on the need for conductive buffers and advanced Cu-based substrates. Methods for preventing Cu oxidation are discussed because it is an anticipated problem for applications using Cu-based rolling assisted biaxially textured substrates (RABiTS).

Low specific contact resistance Ti∕Au contacts on ZnO

Abstract: Ti∕Au Ohmic contacts on heavily Al-doped (n∼1019cm−3) n-ZnO produce low specific contact resistivity of 2.4×10−7Ωcm2 in the as-deposited condition and extremely low minimum values of 6×10−8Ωcm2 after annealing at 300°C.The contact resistance is independent of measurement temperature after low temperature anneals, suggesting that tunneling is the dominant transport mechanism in the contacts. The contact morphology roughens after annealing at 150°C and Auger electron spectroscopy depth profiling shows Zn outdiffusion through the metal and intermixing of Au and Ti. However, the morphology does not significantly worsen after anneals at 450°C. This metallization scheme looks very attractive for the n-electrode of ZnO-based light-emitting diode structures.

CuGaO2 thin film synthesis using hydrogen-assisted pulsed laser deposition

Abstract: Phase formation, crystallinity, and orientation of CuGaO2 thin films is reported in which hydrogen gas is utilized as a reducing reactant during growth to drive the valence state of Cu to +1. At relatively low growth temperatures, the films are a mixture of CuGaO2, Cu2O, and CuGa2O4. At higher temperatures, the majority phase is CuGaO2. The use of H2 during film growth facilitated the formation of the delafossite phase. Phase purity is further improved via high temperature annealing. The formation of the delafossite phase via post-annealing treatment is in agreement with the thermodynamic equilibrium studies of the Cu-Ga-O system, showing that the CuGaO2 phase is thermodynamically stable under the conditions considered. With the post-annealing process, we achieved phase-pure CuGaO2 films with p-type resistivity on the order of 30 Ω cm and carrier density of mid-1017 cm-3.

Anisotropic x-ray absorption effects in the optical luminescence yield of ZnO nanostructures

Abstract: The authors have found that the directionality of the orbital populated following core-level x-ray absorption of a hexagonal nanostructure has a strong influence on the resulting optical luminescence yield spectra. For ZnO, there is an enhancement of the band gap exciton luminescence following O 1s to 2pz relative to 2px,y excitation. The defect luminescence O 1s excitation spectrum also shows sensitivity to the nature of the defect (surface or bulk).

Effects of Zn content on structural and transparent conducting properties of indium-zinc oxide films grown by rf magnetron sputtering

Abstract: Indium-zinc oxide (IZO) films were grown on glass substrates by rf magnetron sputtering using targets of 50mol% In2O3–50mol% In2O3(ZnO)3 and In2ZnkOk+3 (k=3, 4, 5, and 7) at room temperature and 300°C. The difference in Zn content between the films and the sputter targets varied with the growth temperature. The structural, electrical, and optical properties of the IZO films were investigated as a function of Zn content. The crystal structure of IZO films grown at room temperature changed from amorphous to crystalline at a Zn content (Zn∕(Zn+In)) of 68at.%. IZO films grown at 300°C using a target of 50% In2O3–50% In2O3(ZnO)3 had a Zn content of 40at.% and its x-ray diffraction peaks were matched with those of ITO. As the Zn content in IZO thin films grown at 300°C increased from 40to74at.%, the conductivity and optical band gap energy decreased.

Ge∕HfNx diffusion barrier for Cu metallization on Si

Abstract: The properties of Ge∕HfNx have been investigated relative to its use as a diffusion barrier for Cu metallization. The Ge∕HfNx bilayer was grown on p-Si (001) substrates by reactive sputtering, followed by in situ deposition of Cu. Individually annealed films at different temperatures (400–700°C, 1h) were characterized for evidence of Cu transport through the barrier bilayer to the Si substrate. The annealed structures were characterized by x-ray diffraction, energy-dispersive spectroscopy, and high-resolution transmission electron microscopy. The results indicate superior diffusion barrier properties of Ge∕HfNx for Cu metallization on Si compared to that for HfNx (7nm).

Selective and nonselective wet etching of Zn 0.9 Mg 0.1 O/ZnO

Abstract: Wet etch rates at 25°C for Zn0.9Mg0.1O grown on sapphire substrates by pulsed laser deposition (PLD) were in the range 300–1100 nm · min−1 with HCl/H2O (5×10−3−2×10−2 M) and 120–300 nm · min−1 with H3PO4/H2O (5×10−3−2×10−2 M). Both of these dilute mixtures exhibited diffusion-limited etching, with thermal activation energies of 2–3 kCal · mol−1. By sharp contrast, the etch rates for ZnO also grown on sapphire by PLD were much slower in similar solutions, with rates of 1.2–50 nm · min−1 in HCl/H2O (0.01–1.2 M) and 12–54 nm · min−1 in H3PO4/H2O (0.02–0.15 M). The etching was reaction limited over the temperature range 25–75°C, with activation energies close to 6 kCal · mol−1. The resulting selectivity of Zn0.9Mg0.1O over ZnO can be a high as ∼400 with HCl and ∼30 with H3PO4.

Optical characterization of ZnMnO-based dilute magnetic semiconductor structures

Abstract: n-type ZnMnO spin injection layers were grown by pulsed laser deposition on top ofn-ZnMgO∕ZnO∕p-AlGaN∕p-GaN hybrid spin light-emitting diode (LED) structures synthesized by molecular-beam epitaxy. Both the ZnMnO∕ZnMgO∕ZnO∕AlGaN∕GaN structures and control ZnMnO samples show no or very low (up to 10% at the lowest temperatures) optical (spin) polarization at zero field or 5T, respectively. This indicates difficulties in generating spin polarization by optical spin orientation or possible efficient spin losses. The results are similar to those found earlier for GaMnN∕InGaN∕AlGaN spin-LED structures and indicate that these wide-band-gap dilute magnetic semiconductors with weak spin-orbit interaction and hexagonal symmetry are not attractive for spin-LED applications.

ITO∕Ti∕Au Ohmic contacts on n-type ZnO

Abstract: The specific contact resistivity and chemical intermixing of indium-tin-oxide (ITO)∕Ti∕Au Ohmic contacts on n-type bulk ZnO substrates are reported as a function of annealing temperature up to 450°C. A minimum contact resistivity of 4.6×10−6Ωcm2 was obtained at 50°C and the value remained <10−5Ωcm2 for all temperatures up to 450°C, suggesting that the Ti is an effective diffusion barrier which prevents formation of Au–In solid solutions. Optical microscopy of the contacts shows roughening of the morphology after annealing at 450°C. Indium outdiffusion to the surface of the contact stack is significant by 350°C, and Zn outdiffusion is evident by 450°C. Both the In and underlying Ti become oxidized after these higher temperature treatments.

Simulation of vertical and lateral ZnO light-emitting diodes

Abstract: All-ZnO light-emitting diodes (LEDs) offer the promise of a low-cost, brighter alternative to existing GaN-based light emitters for solid-state lighting applications, in part due to the higher exciton binding energy of ZnO. We have used ISE TCAD™ simulations to examine the effect of active, n- and p-layer dopings and thicknesses on the optical output intensity and current-voltage characteristics of both vertical and lateral geometry ZnO LEDs. The latter geometry is attractive for ultralow structures with the ZnO deposited on glass substrates. The current density distribution is more uniform in the vertical structures but there is little difference in optical output power as a function of doping or layer thickness between the two geometries.

Comparative study of HfNx and Hf–Ge–N copper diffusion barriers on Ge

Abstract: The diffusion barrier properties of HfNx and Hf–Ge–N thin films for Cu metallization on Ge are examined. The diffusion barrier films were deposited by reactive sputtering on p-Ge (001) single crystal substrates with varying thicknesses. Cu thin films were then deposited in situ on the diffusion barrier. The multilayer film structure was subsequently annealed in an Ar atmosphere. X-ray diffraction was used to determine the film crystallinity and identify intermetallic phases due to reactions involving the film and substrate. The HfNx and Hf–Ge–N diffusion barrier films remained amorphous for annealing temperatures up to 700°C. At thickness of 50nm, the HfNx films showed superior diffusion barrier properties as compared to Hf–Ge–N based on the appearance of secondary phases due to reactions and changes in the Cu morphology. These results suggest that HfNx is an effective barrier material for Cu integration on Ge.

Ti ∕ Au Ohmic Contacts to Al-Doped n-ZnO Grown by Pulsed Laser Deposition

Abstract: The effect of annealing on the stability of Ti/Au ohmic contacts on heavily Al-doped (n ≈ 10 19 cm -3 ) n-ZnO is reported. Due to the high n-type doping levels in the ZnO, the as-deposited contacts are ohmic with an excellent specific contact resistivity of 2.4 × 10 -7 Ω cm 2 . Subsequent annealing produces a minimum value of 6 × 10 -8 Ω cm 2 after processing at 300°C. The absence of any temperature dependence to the contact resistance indicates that tunneling is the dominant current transport mechanism. Annealing the contact structure at 250°C produces Zn outdiffusion through the Ti/Au, intermixing of Au and Ti, and roughening of the contact surface morphology. The ease of ohmic contact formation to the Al-doped ZnO and extremely low contact resistance achievable even with low-temperature processing makes this metallization scheme attractive in applications where high processing temperatures cannot be employed.