Understanding the effects of larger wafers on the global semiconductor equipment supply chain

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science; in conjunction with the Leaders for Manufacturing Program at MIT, 2009.Includes bibliographical references (p. 98-99).This thesis examines how an investment in 450mm wafers might affect capital equipment suppliers in the semiconductor industry and assesses if the 450mm transition is in the industry's best interest. The 450mm transition is currently scheduled for 2012 by the ITRS (International Technology Roadmap for Semiconductors), but the overall industry remains divided on the issue, and without sufficient consensus, a transition is simply not possible. The cost of developing equipment for a new wafer size has increased dramatically over the last few wafer size transitions. Furthermore, producing more efficient tools also decreases the number of tools needed by the semiconductor manufacturers if growth stays flat. These factors have caused reluctance among equipment suppliers to go ahead with a transition to 450mm wafers. However, the largest semiconductor manufacturers contend that more efficient tools will lead to cheaper products and stronger semiconductor growth. They argue that this growth will make up for supplier revenue lost due to efficiency gains. This thesis analyzes the dynamics of the capital equipment industry. Qualitative factors, such as past performance, recent trends, and the equipment industry's competitive landscape, are considered using Porter's Five Forces model. A quantitative analysis using the author's supplier cost model (SCM), is applied to several potential 450mm transition scenarios, showing that the industry is sensitive to various inputs such as demand variability, tool productivity, and development costs, to name a few.(cont.) These qualitative and quantitative analyses are combined to demonstrate that a transition to 450mm is in the best interest of the semiconductor capital equipment industry. The equipment industry is presently in an unhealthy state, with most firms struggling to maintain a reasonable profit amidst the high competition and volatile market conditions. Consolidation will eventually be the key to improving the industry structure, but consolidation will be a long and slow process if the industry remains on 300mm wafers. 450mm will stimulate consolidation throughout the industry, quickly bringing the industry to a more stable and sustainable state. The transition will likely be a painful process, and many equipment suppliers will have to exit the market, but it will allow fewer suppliers to be more profitable and healthier in the long run.by Daniel George.S.M.M.B.A

The Dark Energy Survey : more than dark energy – an overview

This overview paper describes the legacy prospect and discovery potential of the Dark Energy Survey (DES) beyond cosmological studies, illustrating it with examples from the DES early data. DES is using a wide-field camera (DECam) on the 4 m Blanco Telescope in Chile to image 5000 sq deg of the sky in five filters (grizY). By its completion, the survey is expected to have generated a catalogue of 300 million galaxies with photometric redshifts and 100 million stars. In addition, a time-domain survey search over 27 sq deg is expected to yield a sample of thousands of Type Ia supernovae and other transients. The main goals of DES are to characterize dark energy and dark matter, and to test alternative models of gravity; these goals will be pursued by studying large-scale structure, cluster counts, weak gravitational lensing and Type Ia supernovae. However, DES also provides a rich data set which allows us to study many other aspects of astrophysics. In this paper, we focus on additional science with DES, emphasizing areas where the survey makes a difference with respect to other current surveys. The paper illustrates, using early data (from ‘Science Verification’, and from the first, second and third seasons of observations), what DES can tell us about the Solar system, the Milky Way, galaxy evolution, quasars and other topics. In addition, we show that if the cosmological model is assumed to be +cold dark matter, then important astrophysics can be deduced from the primary DES probes. Highlights from DES early data include the discovery of 34 trans-Neptunian objects, 17 dwarf satellites of the Milky Way, one published z > 6 quasar (and more confirmed) and two published superluminous supernovae (and more confirmed)

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine

[This corrects the article DOI: 10.1186/s13054-016-1208-6.]

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta