International Journal of Engineering Research and General Science Volume 3, Issue 2, March-April, 2015 ISSN 2091-2730 Some Breakthroughs in Nanoelectronics in the Last Decade D R Mishra Department of Physics, R.H.Government Post Graduate College, Kashipur, U.S.Nagar, Uttarakhand -244713 INDIA [email protected], +919456369024 Abstract- Various research groups have contributed in taking electronics from the present micro level to a new nano level, which is needed for reducing the size of electronic devices and making them perform at a faster speed with an improved efficiency. The research groups have succeeded in making molecular level transistors, junction-less transistors, memory transistor (eliminating need for capacitor), trigate transistors (at Intel), faster graphene transistors (at IBM) and organic transistors (NOMFET). There are also attempts to invent technologies for fabrication of nanobased integrated circuits using concept of magnetic dots (at UCLA), nanowires (at Weizmann Institute), carbon nonotubes (at Stanford University). Researchers are working to print nanolevel circuits with inkjet printers using silver ink (at Pennsylvania) and on flexible plastics (at North Carolina State University) which may lead to flexible motherboards, mobiles and laptops. Attempts are also being made for designing nanolevel circuits with less power consumption and faster heat dissipation. Then research groups at West Lafayette and Motorola are working for better displays and monitors with sharper and intense output imaging using Nanowire and Carbon Nanotube technologies. Research groups have also succeeded in improving Random Access Memories MRAM (at University of Illinois, Chicago), MeRAM (at UCLA), NRAM (at Imec and Nantero) and hard disks (Race Track Memory with thousand times more storage capacity) at IBM. Researchers are also working on silicon nanophotonics and on spectrally purer laser for bringing speed in data transmission. These all research innovations and ideas are a leap forward by science and are worth being discussed for any future research in electronics. Keywords:, 3D nanotube circuits, C60, flexible circuits, Graphene, magnetic quantum dots, MeRAM, NOMFET, NRAM, nanoglue, silicon nanophotonics, single molecular transistor, S-DFB laser, OLEDs, race track memory INTRODUCTION Researchers are using nanoelectronics to increase the capabilities of electronics devices, reduce their weight and power consumption. Some of the nano electronics areas, which are being explored in detail, can be introduced as follows. A. REDUCTION IN SIZE: Smaller circuit means faster execution and data transmission. Various research groups are working to build nano level circuits. The researchers, for example, at university of Alberta [1] have constructed a single molecule transistor. A team of researchers led by Prof. Jean-Pierre Colinge at the Tyndall National Institute have reported the design and fabrication of the world‘s first junction less transistor in Nature [2]. Researchers at Center for Nanoscience and Nanotechnology, Tel Aviv University have reported [3] building a sophisticated memory transistor, with carbon C60 molecules, which is capable to both transfer and store energy, eliminating the need for a capacitor. Intel has developed [4] a fundamentally different technology to construct Tri-Gate transistor 3D transistors of size ~ 22 nm. IBM reported [5] the world's Fastest Graphene Transistor, which can be utilized to produce high performance devices and integrated circuits. Researchers at Georgia Institute of Technology have created graphene p-n junctions [6] by transferring films of the promising electronic material to substrates that have been patterned by compounds that are either strong electron donors or electron acceptors. CNRS and CEA researchers have developed a transistor [7] that can mimic the main functionalities of a synapse. This organic transistor, based on pentacene and gold nanoparticles and is known as a NOMFET (Nanoparticle Organic Memory Field-Effect Transistor), has opened the way to new generations of neuro-inspired computers. The researchers in Munich laboratories of Infineon Technologies AG (FSE/NYSE: IFX), in an efforts to create smaller and more powerful structures for integrated circuits, have constructed the world's smallest nanotube transistor, with a channel length of only 18 nm [8]. 1340 www.ijergs.org International Journal of Engineering Research and General Science Volume 3, Issue 2, March-April, 2015 ISSN 2091-2730 B. IMPROVEMENT IN FABRICATION OF CIRCUITS: There are attempts to improve the technology used in the fabrication of circuits for the electronic devices. Researchers at University of California, Los Angeles (UCLA) and Intel Corporation have created advanced ‗magnetic quantum dots', a futuristic semiconductor technology that will pave the way for the next generation of electrical and information technology systems [9]. A team led by Prof. Ernesto Joselevich of the Weizmann Institute‘s Materials and Interfaces Department [10] have successfully created self-integrating nanowires whose position, length and direction can be fully controlled. They then succeeded in creating a transistor from each nanowire on the surface, producing hundreds of such transistors simultaneously. The nanowires were also used to create a more complex electronic component – a functioning logic circuit called an Address Decoder, an essential constituent of computers. A team of Stanford engineers have built [11] a basic computer using carbon nanotubes that runs faster and uses lesser energy than those made from silicon chips. The researchers, at Stanford [12] designed a chip with the most advanced computing and storage elements, made of carbon nanotubes to date, by devising a way to root out the stubborn complication of nanotubes that cause short circuits. Five members of the team (Wei, Patil, Lin, Wong and Mitra) immediately followed up the VMR paper at IEDM with another presentation [13] describing the first multilayer carbon nanotube three-dimensional integrated circuit. Like multilevel parking garages, three-dimensional circuits allow for packing of more units – in this case, transistors – into a confined area. A team of researchers, led by Professor Cherie Kagan, from the University of Pennsylvania, showed [14] that nanoscale particles, or nanocrystals, of the semiconductor cadmium selenide can be "printed" or "coated" on flexible plastics high- performance electronics. Researchers from Georgia Tech, the University of Tokyo and Microsoft Research have developed a novel method to rapidly and cheaply make electrical circuits by printing them with commodity inkjet printers and off-the-shelf materials [15]. Dr. Yong Zhu and his coworkers in North Carolina State University have developed highly conductive and elastic conductors made from silver nanowires, which can be used to develop stretchable electronic devices [16]. Scientists at the Lockheed Martin Space System Advanced Technology Center (ATC) in Palo Alto developed a revolutionary nanotechnology copper-based electrical interconnect material, or solder that can be processed around 200 °C. Once fully optimized, the CuantumFuse™ solder material is expected to produce joints with up to 10 times the electrical and thermal conductivity compared to tin-based materials currently in use [17]. C. INCREASING THE SPEED OF DATA TRANSMISSION: Researchers are integrating silicon nanophotonics components into CMOS integrated circuits and are producing new lasers that help produce the light with much tighter frequency control than previously achieved. This may allow much higher data rates for information transmission over fiber optics. IBM (NYSE: IBM) announced a major advance [18] in the ability to use light instead of electrical signals to transmit information for future computing. The breakthrough technology – called ―silicon nanophotonics‖ – allows the integration of different optical components side-by-side with electrical circuits on a single silicon chip using, for the first time, sub-100nm semiconductor technology. The researchers [19] recently achieved unprecedented spectral purity as a direct consequence of the incorporation of a nano scale corrugation within the multilayered structure of the laser. The purer the tone, the more information it can carry. D. REDUCTION IN POWER CONSUMPTION: UC Berkeley researchers reported [20] to have exploited the special properties of the rare, heavy metal tantalum magnets, as an alternative to transistors because they require far less energy for switching. A team of interdisciplinary researchers at Rensselaer Polytechnic Institute [21] has developed a new method of boosting the heat transfer rate across two different materials with a ―nanoglue‖, which is useful for cooling computer chips and lighting-emitting diode (LED) devices, collecting solar power, harvesting waste heat, and other applications. E. BUILDING BETTER DISPLAYS: We can improve the display screens on electronic devices in terms of their reduced power consumption, decreased weight and thickness. West Lafayette ind. – Engineers created the first "active matrix" display [22] using a new class of transparent transistors made of "nanowires" and circuits - a step toward realizing applications such as e-paper, flexible color monitors and "heads-up" displays in car windshields. The applied research arm of Motorola Inc. developed [23] a working 5- inch color video display prototype based on proprietary Carbon Nanotube (CNT) technology – a breakthrough technique that