Seminar On Nanotechnology By Vijay.N Vishak.M 5th Sem C.S.E
Seminar Contents • History of Nanotechnology. • Introduction of Nanotechnology. • Applications of Nanotechnology. • Information and Communication Technology (ICT). • Nanochip Designing. • Carbon Nanotubes. • Practical applications of Nanotechnology.
The amount of space available to us for information storage (or other uses) is enormous. As first described in a lecture titled, 'There's Plenty of Room at the Bottom' in 1959 by Richard P. Feynman, there is nothing besides our clumsy size that keeps us from using this space. In his time, it was not possible for us to manipulate single atoms or molecules because they were far too small for our tools. He described how the laws of physics do not limit our ability to manipulate single atoms and molecules. Feynman explored the possibility of manipulating the materials at a scale of individual atoms and molecules, imagining the whole of the encyclopedia Britannica written on the head of the pin. Prof. Feynman described such atomic scale fabrication as a bottom-up approach, as opposed to the top-down approach that we are accustomed to. Top-down Manufacturing :- It involves the construction of parts through methods such as cutting, carving and molding. Using these methods, we have been able to fabricate a remarkable variety of machinery and electronics devices. Bottom-up manufacturing :- On the other hand, would provide components made of single molecules, which are held together by covalent forces that are far stronger than the forces that hold together macro-scale components. Further more, the amount of information that could be stored in devices build from the bottom up would be enormous History of Nanotechnology
Introduction to Nanotechnology • Nanoscience is the study of phenomena and manipulation of materials at atomic, molecular and macro-molecule scales, where properties differ significantly from those at a larger scale. • Nanotechnology is the branch of science and engineering which deals with creation of materials, devices, and systems through the manipulation of individual atoms and molecules. The original definition is technology that is built from single atoms and which depends on individual atoms for function. • The goal of nanotechnology is to control individual atoms and molecules to create computer chips and other devices that are thousands of times smaller than current technologies permit. Current manufacturing processes use lithography to imprint circuits on semiconductor materials.
The prefix ‘nano’ is derived from the Greek word for dwarf. One nanometer (nm) is equal to one-billionth of a meter, 10-9 m. • A human hair is approximately 80,000nm wide, and a red blood cell approximately 7000nm wide. Atoms are below a nanometer in size. A nanometer-sized particle is also smaller than living cell and can be seen only with the most powerful microscope available today. • Nanotechnology is the technology of preference to make things small, light and cheap, nanotechnology based manufacturing is a method conceived for processing and rearranging of atoms to fabricate custom products .if we rearrange the atoms in coal, we can get diamond. If we rearrange atoms of sand we can make computer chips etc. • The original definition this technology that is built from single atoms and which depends on individual atoms for function. • Click here to see the Nano-sized particle
Nanosystems It is small systems can be seen as an extension of biotechnology. For example, to create a molecular motor about the size of a virus, scientists have combined genetically engineered proteins with other chemically structured components.
Nanomaterials It is possible to create new kinds of materials by working at the nanolevel. One of the first nanomaterials was the “carbon nanotube”, which conducts electricity better than copper yet is stronger and lighter than steel.
Nanoelectronics Standard computer chips, which soon will have minimum feature sizes below 100 nanometers, will inevitably enter the realm of nanotechnology.
Information and Communication Technology (ICT) • In IT industry the computer chips is formed by charting number of transistors, the building blocks of computer chips, over the past 30 years. • In 1971 there were just 2300 transistors on Intel’s 4004, their first computer chip, with a clock speed of 0.8 million cycles per second. • But because of nanotechnology by 2003 the Intel Xeon processor had 108 million transistors operating at clock speeds in excess of 3,000 million cycles per second. The increase in number of transistors on a chip coupled with increased speed have fuelled the economics of IT industry. • Nanotech and computer chips
The first integrated circuit in 1970 chips have become smaller, faster and more capable. Computer chips consist of "field-effect transistors" (FETs) that form the active circuits on most chips become smaller and smaller they begin to come up with certain problems. • In the computer-chip world, then, nanotech will be characterized by new types of transistor (such as the "single-electron transistor" or SET) and new types of semiconductor device (such as quantum-well and quantum-dot lasers) to operate in the nanotech environment. • In the optical communications industry there is already a commercially available device (wavelength selective switch) which consists of some 100'000 individually moveable mirrors mounted on the surface of a silicon chip about one cm square where each mirrors is few microns across. • The current 130nm technology node that produces the Intel Xeon processor defines the size of the DRAM (Dynamic random access memory) half-pitch (half the distance between two adjacent metal wires in a memory cell). In 1971 Intel 4004 chip used 10,000nm technology; the chips of 2007 and 2013 will require 65nm and 32nm technology, respectively.
Nanochip Designing • In 2000 the semiconductor industry quietly began producing "Nanochips"--chips with features measuring less than 100 nanometers (roughly one thousandth the thickness of a human hair). These devices are found in the average desktop computer today • Reducing the size of features boosts speed and improves the economics of manufacture by allowing more transistors (often more than 50 million) to be put on a single chip. In just a few years, a typical microprocessor will contain about 10 times that number. • INTEL AND INTERNATIONAL TECHNOLOGY ROADMAP FOR SEMICONDUCTORS
Basic Chip making Process • The basic chip making process involves three stages:- • SILICON-ON-INSULATOR technology • ATOMIC LAYER DECOMPOSITION • EXTREME ULTRAVOILET LITHOGRAPHY
Intel’s 65 Nanometer SRAM chips • Intel has claimed to have produced fully functional 65 nanometer SRAM chips using 12-inch (300mm) silicon wafers. They are expected to go into production in 2005. • The chips use a second generation version of Intel's strained silicon, copper interconnect and low-k dielectrics. The 4Mbit SRAM cells are only .57µ2 in size which means that 10 million chips could fit inside the tip of a ball point pen.
Carbon Nanotubes • Carbon Nanotubes are hexagonally shaped arrangements of carbon atoms that have been rolled into tubes. These tiny straw-like cylinders of pure carbon have useful electrical properties. They have already been used to make tiny transistors and one-dimensional copper wire. • Carbon Nanotubes can route signals in microprocessor chips faster than traditional copper or aluminum wires at speeds of up to 10 GHz. Fig :- Multi – walled carbon nanotube
Carbon Nanotubes also have great significance for use in flat-panel displays, microwave generators, devices for electric surge protection, and high intensity lamps. • Carbon Nanotubes are also likely to be used in IT. These tubes can be either conducting or semi conducting and have the potential for memory and storage as well. • Nanotechnology also has prospective applications for display devices, such as the replacement of cathode ray tube (CRT) technology by electron-producing carbon Nanotubes. • Structure of Carbon nanotubes. Fig :-Single-walled carbon Nanotube
Practical Applications of Nanotechnology • Monitoring Patience • Electronics • Automobile • Optical transmission properties • Modern Telecommunications