Development of integrated circuit industry and currenttechnological challengesThe integrated circuit is a small chip that can function as an amplifier, oscillator, timer, microprocessor, or even computer memory. And it is a small wafer, usually made of silicon, that can hold anywhere from hundreds to millions of transistors, resistors, and capacitors. These extremely small electronics can perform calculations and store data, and are used in almost all electronic equipment today. The integrated circuits have two main advantages over discrete circuits, cost and performance. Cost is low because the components of chips are printed as a unit by photolithography rather than being constructed one transistor at a time. Furthermore, packaged integrated circuits use much less material than discrete circuits. And performance is high because the integrated circuits’components switch quickly and consume little power compared to their discrete components, as a result of the small size and close arrangement of the components. Integrated circuits are used in virtually all electronic equipment today and have revolutionized the world [1].Early developments of the integrated circuit date back to 1949, when German engineer Werner Jacobi applied for a patent for an integrated-circuit-like semiconductor amplifying device showing five transistors on a common substrate in a 3-stage amplifier arrangement [2]. Jacobi disclosed small and cheap hearing aids as typical industrial applications of his patent. But, an immediate commercial use of his patent has not been reported. And the idea of the integrated circuit was conceived by Geoffrey W.A. Dummer (1909–2002), a radar scientist working for the Royal Radar Establishment of the British Ministry of Defense. Dummer presented the idea to the public at the Symposium on Progress in Quality Electronic Components in Washington, D.C. on 7 May 1952. He did many to propagate his ideas, and unsuccessfully attempted to build such a circuit in 1956. Otherwise, at that time a precursor idea to the integrated circuit was to create small ceramic squares or wafers, each containing a single miniaturized component. Components could then be integrated and wired into a bidimensional or tridimensional compact grid. This idea, which seemed very promising in 1957, was proposed to the US Army by Jack Kilby and led to the short-lived Micromodule Program. However, as the project was overwhelming, Kilby came up with a new, revolutionary design: the IC [3].Since the first piece of integrated circuit chip invented by Jack Kilby in 1958 and Noyce in 1959 it has significantly change the electronic industry and the world. Just as the Moore’s law s ays that the number of transistors on a chip doubles about every 18 month, the development of integrated circuit was very fast and our life and society also changed rapidly. In the very beginning of integrated circuits there only a few transistors could be placed on a chip, and the scale was large because of the contemporary technology. The first integrated circuits contained only a few transistors, which called Small-Scale Integration (SSI) [4]. And SSI circuits were crucial to early aerospace projects, and vice-versa. As we all know, both the Minuteman missile and Apollo program need lightweight digital computers for their inertial guidance systems. Therefore, the Apollo guidance computer led and motivated the integrated-circuit technology, while the Minuteman missile forced it into mass-production. The demand by the government supported the initial integrated circuit market until costs fell enough to allow companies to enter the industrialand eventually the consumer markets.In the late 1960s, the next development stage of integrated circuits which contains hundreds of transistors on each chip, called "Medium-Scale Integration" (MSI). Apparently, there were attractive economically because while they cost little more to produce than SSI devices, they allowed more complex systems to be produced using smaller circuit boards, less assembly work because of fewer separate components, and so on. And further development, driven by the same economic factors, led to "Large-Scale Integration" (LSI) in the mid 1970s, with tens of thousands of transistors per chip. At this stage integrated circuits such as 1000 bit RAMs, calculator chips, and the first microprocessors, that began to be manufactured in the early 1970s, had fewer than 4000 transistors. And for true LSI circuits, which approaching 10000 transistors began to be produced around 1974 and used as computer main memories as well as second-generation microprocessors. And with the developing of science and technology, the final step starting from the early 1980s to the present was "very large-scale integration" (VLSI). In 1986 the first one megabit RAM chips were introduced, which contained more than one million transistors. Microprocessor chips passed the million transistor mark in 1989 and the billion transistor mark in 2005[5]. And the chips introduced in 2007 containing tens of billions of memory transistors [6], and the trend which cannot be halted. What’s more, to refl ect further growth of the complexity, the term ULSI that stands for "ultra-large-scale integration" was proposed for chips of more than 1 million transistors [7].And to further reducing costs and improving integration there need some new technologies to make the integration circuits, such as wafer-scale integration, system-on-a-chip as well as three-dimensional integrated circuit. Wafer-scale integration [8] (WSI) is a method to make very large integrated circuits that uses an entire silicon wafer to produce a single superchip. Through a combination of large size and reduced packaging, WSI could result in dramatically reduced costs for some systems, especially massively parallel supercomputers. The current state of the art of WSI is being developed. A system-on-a-chip (SOC) is an integrated circuit in which all the components needed for a computer or other system is included on one single chip [9]. The design of such a device can be complex and costly, and building disparate components on a single piece of silicon may compromise the efficiency of some elements. However, these drawbacks can be offset by lower manufacturing and assembly costs and by a greatly reduced power budget. And a three-dimensional integrated circuit [10][11][12] (3D-IC) has two or more layers of active electronic components that are integrated both vertically and horizontally into a single circuit. Communication between layers uses on-die signaling, so power consumption is much lower than in equivalent separate circuits.The feature sizes of integrated circuits have continuously getting smaller and smaller over the years, and the degree of integration keep increasing which allow more circuitry to be packed on each chip. In general, with the shrinking of feature size, almost everything improves, such as the cost per unit and the switching power consumption go down and the speed goes up. However, integrated circuits with nanometer-scale devices have some problems, main among which is leakage current, bad size effect of this kind of nano material. After decades of reengineering repeatedly, silicon transistors began to reach its development limit, and this is a severe problem and a big challenge. Apparently, use silicon as material of integrated circuit cannot meet our requirement, and we need new material or technologies. Fortunately, with the development material science and technology, we found that with the aid of ferroelectric materials [13], thecalculation of computer can no longer use digital logic. By researching the researchers found that we use the ferroelectric material in which the charge can switch rapidly among four different states to store the datum. And the transistors made of this kind of ferroelectric material can use different charge states to express more digital logic than one and zero, and it can hold the charge state without external power. So, these kinds of material can both processes information and store datum. And I think in the future the development of integrated circuits will focus on ferroelectric materials and this kind of material will further improve integrated circuits.What’s more, recently IBM researchers have built the first integrated circuit (IC) based on a graphene transistor [14], another step toward overcoming the limits of silicon and a potential path to flexible electronics. The circuit, built on a wafer of silicon carbide, consists of field-effect transistors (FETs) made of graphene, a highly conductive chicken-wire-like arrangement of carbon that's a single atomic layer thick. The integrated circuit also includes metallic structures, such as on-chip inductors and the transistors' sources and drains. The work is described in this week's issue of Science. Researchers say that graphene, which has the potential to make transistors that operate at terahertz speeds, could one day supplant silicon as the basis for computer chips. Otherwise, one remarkable feature is that the performance of the device didn't change very much when its temperature went from about 27 °C to 127 °C. And that means a graphene circuit won't have to be overdesigned to compensate for temperature changes, potentially leading to a less-complex and less-expensive circuit. But, there are two main difficulties [15]: One is that the metals used to make other parts of the circuit, such as aluminum, gold, and palladium, don't adhere very well to the graphene. The other is the fact that graphene, being only a single atom thick, is easily damaged by standard semiconductor etching processes.Finally, the developments of integrated circuits have pushed the development of electronic industry and still play a vital role in our society. Although, it seemed reach its limitation in silicon material, with the development of material science and technology, new materials, grapheme and ferroelectric material, have developed and researched to make new type integrated circuits. And them will further promote the development of electronic industry and change our society and life largely.Reference________________[1]"Integrated circuits help Invention". . Retrieved 2012-08-13.[2]DE 833366 W. Jacobi/SIEMENS AG: …Halbleiterverstärker“ priority filing on 14 April 1949,published on 15 May 1952.[3]Briddock D. The Integrated Circuit[J]. Micro Mart, 2013.[4]Mark Melliar-Smith C, Haggan D E, Troutman W W. Key steps to the integrated circuit[J].Bell Labs Technical Journal, 1997, 2(4):15–28.[5]Havemann R H, Hutchby J A. High-performance interconnects: An integration overview[J].Proceedings of the IEEE, 2001, 89(5):586--601.[6]Peter Clarke, EE Times: Intel enters billion-transistor processor era, 14 November 2005.[7]Meindl, J.D. 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