Presented By:
R.Durga Devi,
N.Pavithra

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ABSTRACT:
Nanotechnology is one of the fast developing branches of hybrid science combining physics, chemistry and engineering. One of the major implications of this technology will have on the future field of engineering. Future computer chips will contain more circuitry and components, causing them to generate additional heat and requiring innovative cooling methods.
This paper explains the role of nanotechnology in increasing the efficiency of the computer. The most innovative and emerging technique, using a liquid to cool electronic circuits, however, poses many challenges, as they are expensive and prone to breakdown. So, our aim here is to create a type of system for the chips to cool such that the challenges hindered are overcome. Thus industry has developed a new cooling method that uses air. The key attribute of this work is that it sticks with air cooling while possibly providing the same rate of cooling as a liquid. We explain the cooling of future computers using nanotechnology. This method uses new type of cooling technology for computers that uses a sort of nano-lightning to create tiny wind of currents that would self-cool the chips without any requirement of an external mean. It explains about the carbon nanoribbons for smaller, speedier computer chips and also the computer memory designed in nano scale.
INDEX TERM OVERCLOCKING: Extra cooling which is usually required by those who run parts of their computer (such as the CPU and GPU) at higher voltages and frequencies than manufacturer specifications call for.
INTRODUCTION
The present trends used for reducing the heat in the computer are Liquid submersion cooling, Passive heat-sink cooling, Active heat-sink cooling, Peltier cooling or thermoelectric cooling, Water cooling Heat pipe ,Phase-change cooling, Integrated chip cooling techniques. However these techniques possess certain drawbacks which can be overcome by the new technique. The new technique works by generating ions or electrically charged atoms using electrodes placed close to one another on a computer chip. Generated ions are passed from electrode to electrode, with collisions between ions and neutral air atoms propelling the air forward in what is called the corona wind effect – the process that cools. The nanoscale computer memory can retrieve data 1000 times faster than the normal wire. The entire thing would sit on, and be integrated into, a chip that is 10mmx10mm.
CAUSES OF HEAT GENERATION
The amount of heat generated by an integrated circuit (e.g., a CPU), the prime cause of heat build up in modern computers, is a function of the efficiency of its design, the technology used in its construction and the frequency and voltage at which it operates. In operation, the temperature of a computer's components will rise until the heat lost to the surroundings is equal to the heat produced by the component, and thus the temperature of the component reaches equilibrium. For reliable operation, the equilibrium temperature must be sufficiently low for the structure of the computer's circuits to survive. Some of popular cooling techniques are discussed below:
PASSIVE HEAT-SINK COOLING
Passive heat-sink cooling involves attaching a block of machined or extruded metal to the part that needs cooling. A thermal adhesive may be used More commonly for a personal-computer CPU, a clamp holds the heat sink directly over the chip, with a thermal grease or thermal pad spread between. This block usually has fins and ridges to increase its surface area. The heat conductivity of metal is much better than that of air, and it radiates heat better than does the component that it is protecting (usually an integrated circuit or CPU). Until recently, fan-cooled aluminium heat sinks were the norm for desktop computers. Today, many heat sinks feature copper base-plates or are entirely made of copper, and mount fans of considerable size and power.
Dust buildup between the metal fins of a heat sink gradually reduces efficiency, but can be countered with a gas duster by blowing away the dust along with any other unwanted excess material. Passive heat sinks are commonly found on older CPUs, parts that do not get very hot (such as the chipset), and low-power computers.
Usually a heat-sink is attached to the integrated heat spreader (IHS), essentially a large, flat plate attached to the CPU, with conduction paste layered between. This dissipates or spreads the heat locally. Unlike a heat sink, a spreader is meant to redistribute heat, not to remove it. In addition, the IHS protects the fragile CPU.Passive cooling involves no fan noise.
ACTIVE HEAT-SINK COOLING
Active heat-sink cooling uses the same principle as passive, with the addition of a fan that blows over or through the heat sink. The air movement increases the rate at which the heat sink can exchange heat with the ambient air. Active heat sinks are the primary method of cooling modern processors and graphics cards.
The buildup of dust is greatly increased with active heat-sink cooling, because the fan continually takes in the dust present in the surrounding air.
WATER COOLING
While originally limited to mainframe computers, water cooling has become a practice largely associated with overclocking in the form of either manufactured kits, or in the form of do-it-yourself setups assembled from individually gathered parts. The past few years has seen water cooling increasing its popularity with pre-assembled, moderate to high performance, desktop computers. Water has the ability to dissipate more heat from the parts being cooled than the various types of metals used in heat sinks, making it suitable for overclocking and high performance computer applications.
Advantages to water cooling include the fact that a system is not limited to cooling one component, but can be set up to cool the central processing unit, graphics processing unit, and/or other components at the same time with the same system. As opposed to air cooling, water cooling is also influenced less by the ambient temperature. Water cooling's comparatively low noise-level compares favorably to that of active cooling, which can become quite noisy. One disadvantage to water cooling is the potential for a coolant leak. Leaked coolant can damage any electronic components it comes in contact with. Another drawback to water cooling is the complexity of the system; an active heat sink is much simpler to build, install, and maintain than a water cooling solution.
HEAT PIPE
A heat pipe is a hollow tube containing a heat transfer liquid. As the liquid evaporates, it carries heat to the cool end, where it condenses and then returns to the hot end. Heat pipes thus have a much higher effective thermal conductivity than solid materials. For use in computers, the heat sink on the CPU is attached to a larger radiator heat sink. Both heat sinks are hollow as is the attachment between them, creating one large heat pipe that transfers heat from the CPU to the radiator, which is then cooled using some conventional method. This method is expensive and usually used when space is tight or absolute quiet is needed. Because of the efficiency of this method of cooling, many desktop CPUs and GPUs, as well as high end chipsets, use heat pipes in addition to active fan-based cooling to remain within safe operating temperatures.
USE OF ROUNDED CABLES
Most older PCs use flat ribbon cables to connect storage drives. These large flat cables greatly impede airflow by causing drag and turbulence. Overclockers and modders often replace these with rounded cables, with the conductive wires bunched together tightly to reduce surface area. Theoretically, the parallel strands of conductors in a ribbon cable serve to reduce crosstalk (signal carrying conductors inducing signals in nearby conductors), but there is no empirical evidence of rounding cables reducing performance. This may be because the length of the cable is short enough so that the effect of crosstalk is negligible. Problems usually arise when the cable is not electromagnetically protected and the length is considerable, a more frequent occurrence with older network cables.
In order to have a still better efficiency of the computer, the cooling devices, cables are replaced by nanotechnology.
NANOTECHNOLOGY
The word nanotechnology is derived from the Greek word ‘nanos’ meaning ‘dwarf’. Nanotechnology involves working with matter at the scale of one-billionth of a meter (1mm). It refers to the manipulation of matter on the minutest scale i.e. atoms and molecules. Fig (5) shows the process of Atom.