J. Appl. Cryst.の発刊に際して

This paper gives the 2010 self-consistent set of values of the basic constants and conversion factors of physics and chemistry recommended by the Committee on Data for Science and Technology (CODATA) for international use. The 2010 adjustment takes into account the data considered in the 2006 adjustment as well as the data that became available from 1 January 2007, after the closing date of that adjustment, until 31 December 2010, the closing date of the new adjustment. Further, it describes in detail the adjustment of the values of the constants, including the selection of the final set of input data based on the results of least-squares analyses. The 2010 set replaces the previously recommended 2006 CODATA set and may also be found on the World Wide Web at physics.nist.gov/constants.

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CODATA Recommended Values of the Fundamental Physical Constants: 2006

Fuel cells are uniquely capable of overcoming combustion efficiency limitations (e.g., the Carnot cycle). However, the linking of fuel cells (an energy conversion device) and hydrogen (an energy carrier) has emphasized investment in proton-exchange membrane fuel cells as part of a larger hydrogen economy and thus relegated fuel cells to a future technology. In contrast, solid oxide fuel cells are capable of operating on conventional fuels (as well as hydrogen) today. The main issue for solid oxide fuel cells is high operating temperature (about 800°C) and the resulting materials and cost limitations and operating complexities (e.g., thermal cycling). Recent solid oxide fuel cells results have demonstrated extremely high power densities of about 2 watts per square centimeter at 650°C along with flexible fueling, thus enabling higher efficiency within the current fuel infrastructure. Newly developed, high-conductivity electrolytes and nanostructured electrode designs provide a path for further performance improvement at much lower temperatures, down to ~350°C, thus providing opportunity to transform the way we convert and store energy.

http://science.sciencemag.org/content/sci/334/6058/935.full.pdf

Lowering the Temperature of Solid Oxide Fuel Cells

Review on recent progress of nanostructured anode materials for Li-ion batteries

The role of extended and point defects, and key impurities such as C, O, and H, on the electrical and optical properties of GaN is reviewed. Recent progress in the development of high reliability contacts, thermal processing, dry and wet etching techniques, implantation doping and isolation, and gate insulator technology is detailed. Finally, the performance of GaN-based electronic and photonic devices such as field effect transistors, UV detectors, laser diodes, and light-emitting diodes is covered, along with the influence of process-induced or grown-in defects and impurities on the device physics.

Gan : processing, defects, and devices

The interactions between end of range dislocation loops and ·311× defects as a function of their proximity was studied. The dislocation loops were introduced at 2600 A by a dual 1 × 1015 cm-2, 30 keV and a 1 × 1015 cm-2, 120 keV Si+ implantation into Silicon followed by a anneal at 850 °C for 30 minutes. The depth of the loop layer from the surface was varied from 2600 A to 1800 A and 1000 A by polishing off the Si surface using a chemical-mechanical polishing (CMP) technique. A post-CMP 1 × 1014 cm-2, 40 keV Si+ implantation was used to create point defects at the projected range of 580 A. The wafers were annealed at 700, 800 and 900 °C and plan-view transmission electron microscopy (TEM) study was performed. It was found that the number of interstitials in ·311× defects decreased as the projected range damage was brought closer to the loop layer, while the number of rectangular elongated defects (REDs) increased. Experimental investigation showed that REDs are formed at the end-of-range. It is concluded that the interstitials introduced at the projected range are trapped at the end-of-range dislocations. The REDs are formed due to the interactions between the interstitials and the pre-existing loops.

Effect of the End of Range Loop Layer Depth on the Evolution of {311} Defects

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005

/pdf/using-a-focused-ion-beam-to-characterize-the-microstructure-am8idg3yyd.pdf

Using a Focused Ion Beam to Characterize the Microstructure of Porous Lanthanum Strontium Manganite (LSM) Electrodes

As the fabrication for the CMOS technology trends to decreasing the size of transistors for the benefit of increased performance and device density, the implant and annealing process technologies are being forced to meet increasingly challenging demands for ultra-shallow junctions. As the current annealing preferences shift from rapid thermal annealing toward sub-second RTP technologies such as flash and laser annealing, the dynamics of micro-structural evolution on the order of milliseconds and microseconds become of increasing importance. To investigate the kinetics in this ultra-fast annealing regime, this study investigated the effect of varying the temperature and time of a scanning laser anneal in the millisecond and microsecond timeframe. Amorphous layers were created in silicon substrates using a 30 keV silicon implant at a dose of 1x1015 ions/cm3. These wafers were then processed using a scanning continuous wave near infra-red laser at varying temperatures and scan rates in order to vary the dwell time of each condition. A combination of sheet resistance, optical interferometry, and secondary ion mass spectrometry characterization techniques were used in order to investigate the activation and diffusion of these laser annealed samples. The regrowth temperature across all samples showed a positive correlation to the sheet resistance; trending toward lower values as temperatures increased. Dwell time, however, showed an inverse effect at lower temperatures. The microsecond anneal at 1200 °C showed a lower Rs than the millisecond anneal, while at higher temperatures the trend reversed. This trending shows an obvious competition between activation and diffusion mechanisms and their dependence on regrowth temperature.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S194642740008653X

Effect of Varying Dwell Time During Non-melt Laser Annealing of Boron Implanted Silicon

Electron cyclotron resonance (ECR) discharges of HBr/Ar, HBr/H 2 , or HBr/CH 4 were used for dry etching of Ga-based (GaAs, GaSb, and AlGaAs) and In-based (InP, InAs, InSb, InGaAs, and InAlAs) III-V semiconductors. The effects of variations in pressure (1-20 mTorr), gas composition, and additional RF-induced bias on the sample were examined. At least -100 V of dc bias is required to initiate etching under all conditions, with the etch rates found to be fastest with CH 4 addition, followed by H 2 and then Ar

Characteristics of III‐V Dry Etching in HBr‐Based Discharges.

The enhanced diffusion of boron due to high dose arsenic implantation into silicon is studied as a function of arsenic dose. The behavior of both the type-V and end-of-range loops is investigated by transmission electron microscopy (TEM). The role of arsenic deactivation induced interstitials and type-V loops on enhanced diffusion is assessed. Reduction of the boron diffusivity is observed with increasing arsenic dose at three different temperatures. The possible explanations for this reduction are discussed.

Kevin S. Jones

Papers

Effect of the End of Range Loop Layer Depth on the Evolution of {311} Defects

Using a Focused Ion Beam to Characterize the Microstructure of Porous Lanthanum Strontium Manganite (LSM) Electrodes

Effect of Varying Dwell Time During Non-melt Laser Annealing of Boron Implanted Silicon

Characteristics of III‐V Dry Etching in HBr‐Based Discharges.

Effects of arsenic deactivation on arsenic-implant induced enhanced diffusion in silicon