Heat Transport

Volume 1-B contains the following chapters: (1) blanket and reflector; (2) central cell shield; (3) central cell structure; (4) heat transport and energy conversion; (5) tritium systems; (6) cryogenics; (7) maintenance; (8) safety; (9) radioactivity, activation, and waste disposal; (10) instrumentation and control; (11) balance of plant; (12) plant startup and operation; (13) plant availability; (14) plant construction; and (15) economic analysis.

Power dissipation is expected to increase exponentially to 150-250 W per chip over the next decade. To manage this large heat output, it is necessary to minimize the thermal resistance between the chip and a heat dissipation unit that the device is attached to. It is therefore important to further improve the thermal performance of thermal interface materials (TIMs), which can be achieved through 1) improvement of the bulk thermal conductivity of TIMs; and/or 2) reduction of interfacial thermal resistances between the TIM and the device and/or TIM and the heat dissipation unit. The latter improvement may be obtained by enhanced physical properties of TIMs (e.g., viscosity or wetting ability) and/or surface modification of the heat dissipation unit or the inactive side of the device. Researchers have tried to take advantage of the high 1D thermal conductivities of graphite fibers, and more recently of carbon nanotubes (CNT), to reduce the thermal resistance between the chip and the h...

Medieval Climate Anomaly (MCA) terrestrial proxy records (speleothem, NW Scotland; tree rings, Morocco) from close to the centres of action of the winter North Atlantic Oscillation (NAO) indicate that the MCA was characterized by a pervasive positive phase of the NAO(1). Spatial gradients across Europe in this MCA synoptic climatological interpretation were analyzed using the Proxy Surrogate Reconstruction approach based

Power dissipation is expected to increase exponentially to 150-250 W per chip over the next decade. To manage this large heat output, it is necessary to minimize the thermal resistance between the chip and a heat dissipation unit that the device is attached to. It is therefore important to further improve the thermal performance of thermal interface materials (TIMs), which can be achieved through 1) improvement of the bulk thermal conductivity of TIMs; and/or 2) reduction of interfacial thermal resistances between the TIM and the device and/or TIM and the heat dissipation unit. The latter improvement may be obtained by enhanced physical properties of TIMs (e.g., viscosity or wetting ability) and/or surface modification of the heat dissipation unit or the inactive side of the device. Researchers have tried to take advantage of the high 1D thermal conductivities of graphite fibers, and more recently of carbon nanotubes (CNT), to reduce the thermal resistance between the chip and the heat dissipation unit. The efforts can be classified into three categories: 1) Forming pre-aligned graphite fiber or CNT films that have high bulk thermal conductivities in the heat transport direction, and applying such films as TIMs; 2) incorporating randomly oriented graphite fibers or CNT into silicone or epoxy matrices in the presence or absence of a second filler to improve bulk thermal conductivities, and applying the thus-formed blend as thermal greases, or adhesives or gels; and 3) growing CNT or graphite fibers from the heat sink/spreader surface and/or silicon backside and assembling them together with a TIM a to increase the bulk heat transport property and reduce the interfacial resistances, In this paper, we will present results for each of the three approaches, and discuss the challenges facing each one.

We report on the thermal failure of fin-shaped field-effect transistor (FinFET) devices under the normal operating condition. Pre- and post failure characteristics are investigated. A detailed physical insight on the lattice heating and heat flux in a 3-D front end of the line and complex back end of line-of a logic circuit network-is given for bulk/silicon-on-insulator (SOI) FinFET and extremely thin SOI devices using 3-D TCAD. Moreover, the self-heating behavior of both the planar and nonplanar devices is compared. Even bulk FinFET shows critical self-heating. Layout, device, and technology design guidelines (based on complex 3-D TCAD) are given for a robust on-chip thermal management. Finally, an improved framework is proposed for an accurate electrothermal modeling of various FinFET device architectures by taking into account all major heat flux paths.

The earth's largest ocean rings are spawned near 8°N in the western tropical Atlantic from the equator-crossing North Brazil Current (NBC). NBC rings, which can exceed 450 km in diameter and 2000 m in vertical extent, translate northwestward parallel to the South American coastline until they collide with the Lesser Antilles in the southeastern Caribbean Sea. The rings entrain filaments of nutrient- and sediment-rich Amazon and Orinoco River discharge, impact the distribution of icthyoplankton, and pose a physical threat to expanding offshore oil and gas exploration. The six rings generated annually are also responsible for up to one-third of the equatorial-to-subtropical mass and heat transport associated with the Atlantic meridional overturning circulation, a fundamental component of the earth climate system. Recent RAFOS float and surface drifter trajectories illustrate the translation and structural evolution of several NBC rings and enable the determination of the downstrea...