An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Semiconductor device, and manufacturing method thereof

Here we show through an order-of-magnitude analysis that the enhancement in the effective thermal conductivity of nanofluids is due mainly to the localized convection caused by the Brownian movement of the nanoparticles. We also introduce a convective-conductive model which accurately captures the effects of particle size, choice of base liquid, thermal interfacial resistance between the particles and liquid, temperature, etc. This model is a combination of the Maxwell-Garnett (MG) conduction model and the convection caused by the Brownian movement of the nanoparficles, and reduces to the MG model for large particle sizes. The model is in good agreement with data on water, ethylene glycol, and oil-based nanofluids, and shows that the lighter the nanoparticles, the greater the convection effect in the liquid, regardless of the thermal conductivity of the nanoparticles.

Brownian-motion-based convective-conductive model for the effective thermal conductivity of nanofluids

The purpose of this literature review is to compare different cooling technologies currently in development in research laboratories that are competing to solve the challenge of cooling the next generation of high heat flux computer chips. Today, most development efforts are focused on three technologies: liquid cooling in copper or silicon micro-geometry heat dissipation elements, impingement of liquid jets directly on the silicon surface of the chip, and two-phase flow boiling in copper heat dissipation elements or plates with numerous microchannels. The principal challenge is to dissipate the high heat fluxes (current objective is 300 W/cm2) while maintaining the chip temperature below the targeted temperature of 85°C, while of second importance is how to predict the heat transfer coefficients and pressure drops of the cooling process. In this study, the state of the art of these three technologies from recent experimental articles (since 2003) is analyzed and a comparison of the respective merits and ...

State of the Art of High Heat Flux Cooling Technologies

An organic light-emitting diode (OLED) display is disclosed. In one aspect, the display includes a stretchable substrate, a thin film transistor (TFT) formed over the stretchable substrate and including a plurality of electrodes, an OLED electrically connected to the TFT and including a plurality of electrodes, and a plurality of interconnection lines connected to the electrodes of the OLED and the TFT. At least one of the interconnection lines is configured to move in a stretching direction and rotate an electrode selected from the electrodes of the OLED and the TFT connected to the at least one interconnection line.

Organic light-emitting diode display

Continued miniaturization and demand for high-end performance of electronic devices and appliances have led to dramatic increase in their heat flux generation. Consequently, conventional coolants and cooling approaches are increasingly falling short in meeting the ever-increasing cooling needs and challenges of those high heat generating electronic devices. This study provides a critical review of traditional and emerging cooling methods as well as coolants for electronics. In addition to summarizing traditional coolants, heat transfer properties and performances of potential new coolants such as nanofluids are also reviewed and analyzed. With superior thermal properties and numerous benefits nanofluids show great promises in fulfilling the cooling demands of high heat generating electronic devices. It is believed that applications of such novel coolants in emerging techniques like micro-channels and micro-heat pipes can revolutionize cooling technologies for electronics in the future.

A critical review of traditional and emerging techniques and fluids for electronics cooling

This paper describes a practical implementation of a single-phase Si microchannel cooler designed for cooling very high power chips such as microprocessors. Through the use of multiple heat exchanger zones and optimized cooler fin designs, a unit thermal resistance 10.5 C-mm2 /W from the cooler surface to the inlet water was demonstrated with a fluid pressure drop of <35kPa. Further, cooling of a thermal test chip with a microchannel cooler bonded to it packaged in a single chip module was also demonstrated for a chip power density greater than 300W/cm2. Coolers of this design should be able to cool chips with average power densities of 400W/cm2 or more

A Practical Implementation of Silicon Microchannel Coolers for High Power Chips

The paper describes a practical implementation of a single-phase Si microchannel cooler designed for cooling very high power chips such as microprocessors. Through the use of multiple heat exchanger zones and optimized cooler fin designs, a unit thermal resistance of 10.5 C-mm/sup 2//W from the cooler surface to the inlet water was demonstrated with a fluid pressure drop of less than 35 kPa. Further, cooling of a thermal test chip with a microchannel cooler bonded to it packaged in a single chip module was also demonstrated for a chip power density greater than 300 W/cm/sup 2/. Coolers of this design should be able to cool chips with average power densities of 400 W/cm/sup 2/ or more.

A practical implementation of silicon microchannel coolers for high power chips

The present invention relates generally to a new apparatus and method for encapsulating ceramic chip carriers. More particularly, the invention encompasses an apparatus and a method for providing a fluid-tight, non-hermetic seal to a ceramic chip carrier utilizing dual surfaces. This is done by using the corner edges of the chip carrier, i.e., by using not only a minimal amount of the top-surface real estate of the chip carrier, but also the side-walls of the chip carrier to create the dual surface seal. This dual surface seal can be both hermetic and non-hermetic.

Enhanced protection of semiconductors with dual surface seal

A heat sink assembly and method for attaching a multi-chip module cap to a polymeric heat sink adhesive by means of a thin adhesion-promoting metal film layer, which provides an interfacial bond between the cap and polymeric adhesive meeting package performance and reliability requirements. There is also a method of promoting adhesion between a silicon-containing polymeric adhesive and a metal surface using the thin adhesion-promoting metal film layer and the products thereof.

Adhesion promoting layer for bonding polymeric adhesive to metal and a heat sink assembly using same

The present invention relates generally to apparatus and methods for cooling semiconductor integrated circuit (IC) chip package structures. More specifically, the present invention relates to apparatus and methods for thermally coupling semiconductor chips to a heat conducting device (e.g., copper thermal hat or lid) using a compliant thermally conductive material (e.g., thermal paste), wherein a thermal interface is designed to prevent/inhibit the formation of voids in the compliant thermally conductive material due to the flow of such material in and out from between the chips and the heat conducting device due to thermal cycling.

Hilton T. Toy

Papers

A Practical Implementation of Silicon Microchannel Coolers for High Power Chips

A practical implementation of silicon microchannel coolers for high power chips

Enhanced protection of semiconductors with dual surface seal

Adhesion promoting layer for bonding polymeric adhesive to metal and a heat sink assembly using same

Apparatus and Methods for Cooling Semiconductor Integrated Circuit Package Structures