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Private transportation was transformed by mass ownership of automobiles while long-distance public transport benefited from new high-speed trains and from affordable flying. Freight transportation was transformed by containers moved by ships, trains, and trucks. Communication and the processing and dissemination of information were revolutionized first by transistors, then by integrated circuits and microprocessors, the key components of mainframe and personal computers, televisions, and a multitude of electronic devices, many of them now taking advantage of the Internet.

This chapter describes the role of information technology in two electronic media industries over time: radio and TV. It describes their applications in business practices, recording and transmission of programs, role over the Internet, and the effects on firms in these industries, beginning with transistor radios to the Internet.

This chapter treats transistors, their noise properties, and applications to basic circuits. First, the physics of bipolar transistors is discussed with an emphasis on device parameters important for circuit design. The properties of common emitter, common base, and common collector (emitter follower) circuits are discussed together with extensions to cascode and differential amplifiers. The analogous treatment is applied to junction field effect transistors (JFETs) and metal oxide semiconductor devices (MOSFETs). Noise properties of bipolar and field effect transistors are derived together with their dependence on device parameters and operating conditions. These results are then applied to the overall noise when used with a detector and pulse shaper. Low power operation is essential in large-scale strip and pixel detectors, so the closing sections discuss techniques to optimize the balance between noise, speed, and power.

This chapter first explains basic radiation damage mechanisms (i.e., displacement and ionization damage), and then applies them to sensors and transistors. Radiation damage in detector diodes manifests itself as an increase in reverse bias current, changes in the required bias voltage, and carrier losses due to trapping. Space charge buildup due to displacement damage in depletion layers is described, which leads to a strong increase in the required bias voltage vs. temperature and time (anti-annealing). The effects of radiation damage on operating parameters and noise of field effect transistors (JFETs, MOSFETs) and bipolar transistors are discussed, together with annealing phenomena, e.g., low dose enhancement in bipolar transistors. The closing section discusses mitigation techniques, showing the interplay of system architecture, device parameters, and operating conditions.

The first all-purpose digital computer, completed in 1946, was developed by John W. Mauchly and J. Prosper Eckert, and associates at the University of Pennsylvania’s Moore School of Electrical Engineering, with funding from the U.S. Army Ballistic Research Laboratory. The first working transistor emerged from the solid state research program at Bell Laboratories led by William Schokley, John Bardeen, and Walter Brattain. The transition between initial development of the transistor and the subsequent development of military and commercial application in the 1950s were substantially funded by the Army Signal Corps. Intensification of the Cold War in the early 1950s provided the impetus for IBM to develop a fully transistorized computer for commercial use. Development of the integrated circuit at Texas Instruments in the late 1950s and of the microprocessor at Intel in the late 1960s set the stage for the development of both modern supercomputers and the personal computer.

This chapter describes the work leading to the invention of the point-contact transistor at Bell Labs in 1947 by John Bardeen, Walter Brattain, and William Shockley, together with Shockley's later proposal for the junction transistor. It explains the context of the work, which can be described as ‘planned research’, involving teams of scientists with specific aims in view. The chapter also contains accounts of the physics and technology of silicon and germanium, describing zone-refining methods for purifying silicon or germanium boules and the Czochralski method for growing high quality single crystals from the melt. The band structure of these semiconductors is then described, introducing the concepts of their indirect band gaps, optical properties, effective masses, and free carrier mobilities. The importance of surface states in determining surface band-bending is emphasised. Minority carrier diffusion is discussed within the context of transistor action. The evolution of transistor technology is described.

This chapter recounts the group of eight scientists' move from Shockley Semiconductor Labs to Fairchild Semiconductor Corporation, which was established under an agreement with Fairchild Camera and Instrument. A deal with IBM was key to the success of Fairchild Semiconductor. IBM wanted a transistor that could withstand high temperatures and that could switch quickly. By May 1958, the NPN transistor Moore's team had built for IBM was ready to move into production. By early summer, Fairchild Semiconductor had delivered its promised 100 devices to IBM.

This chapter focuses on Noyce's capacity for innovation and his development of the integrated circuit. The early years of Fairchild Semiconductor were also a most intellectually fertile time for Noyce. Seven of his seventeen patents, including his most important for the integrated circuit, date from the eighteen months after the company was launched.

By incorporating spin-dependent properties and magnetism in semiconductor structures, new applications can be considered which go beyond magnetoresistive effects based on metallic systems. Notwithstanding the prospects for spin/magnetism-enhanced logic in semiconductors, many important theoretical, experimental, and materials challenges remain. This chapter discusses the challenge for realizing a particular class of applications: the proposal here is for bipolar spintronic devices in which carriers of both polarities (electrons and holes) contribute to spin-charge coupling. Nonlinear current-voltage characteristics, large deviations from local charge neutrality, as well as inhomogeneous built-in and applied fields, all have important implications on the bipolar transport and potential spin-based logic applications. This chapter formulates the theoretical framework for bipolar spin-polarized transport, and describes the novel effects in two- and three-terminal structures which arise from the interplay between nonequilibrium spin and equilibrium magnetization.

Ultrasmall systems called quantum dots (QDs) and single-electron transistors, where Coulomb interaction (Coulomb blockade) plays an important role, are very interesting and promising devices, which allow for control and manipulation of a single spin. With quantum dots, due to the control of a single electron charge, the possibility for manipulation of a single spin is opened up, which can be important for spintronics and quantum computing. On the level of a few spins, the new physics related to exchange interaction, spin blockade, Larmor precession, electron spin resonance (ESR), the Kondo effect, and hyperfine interactions with nuclear spins is raised. Also combining ferromagnetic materials with QDs opens up a new possibility of control and manipulation of a QD single spin by direct exchange interactions and construction of ferromagnetic single-electron transistors (F-SET).

This chapter presents simple ideas for understanding how spin-polarized currents can be used to exert spin-transfer torques in magnetic devices. The chapter reviews recent progress for measuring the magnetic dynamics that result from spin-transfer torques in 100-nm-scale metallic spin valves and magnetic tunnel junctions. The chapter also discusses how the transport of spin and charge in magnetic devices changes when the structures are made even smaller, extending from magnetic particles a micron in diameter, to a few nanometers, and down to a single molecule. As the size of the magnet shrinks, effects such as Coulomb blockade and energy-level quantization can become dominant, and it becomes necessary to move beyond simple independent-electron models to consider the true correlated many-electron quantum states at the root of ferromagnetism.

Highly spin-polarized electron currents can be engineered in magnetic nanostructures by utilizing spin dependent tunneling and spin dependent scattering effects. In magnetic tunnel junctions with crystalline MgO barriers, a giant asymmetry in tunneling probability for the majority and minority electrons gives rise to currents which are more than 85% spin polarized at low temperatures and corresponding tunneling magnetoresistance values of more than 200% at room temperature. In a three terminal magnetic tunnel transistor (MTT), the electron current is further spin-filtered in a magnetic base layer so that the collector current can become nearly completely spin-polarized. The MTT allows for the exploration of spin dependent scattering of hot electrons and can be used as a spin injector into semiconductors, but the high energy of the injected electrons leads to modest values of spin polarization. More highly spin polarized currents can be injected into semiconductors using tunnel spin injectors such as CoFe/MgO.

This chapter describes the establishment of silicon as the dominant semiconductor in modern electronics. Not only was it the preferred material for the manufacture of integrated circuits, but also for the development of power devices. The invention of the integrated circuit by Jack Kilby at Texas Instruments is described, together with that of the planar IC by Robert Noyce at Fairchild Semiconductor. The subsequent growth of IC technology is outlined, depending very largely on the invention of the MOS transistor in 1960. A brief outline is given of silicon wafer production and the application of photolithography in defining IC patterns. Moore's Law is explained and a short discussion of Japanese successes in the IC business during the 1970s is interpolated. The parallel development of silicon power devices is described, together with a selection of typical applications. The chapter concludes with an account of some exciting developments in silicon physics, including the discovery of the quantum Hall effect.

This chapter introduces the advent of compound semiconductors. III-V materials such as GaAs and InP found applications in semiconductor electronics during the 1960s, where silicon's electronic properties were unsuitable. For example, their electron mobilities were far greater than that of silicon, thus enabling them to compete in the field of microwave transistors. The direct band gap of GaAs made it suitable for LEDs and in 1962 the first semiconductor lasers were reported, leading to the first commercial application in 1978 in the CD player. The GaAs Gunn diode was invented in 1963 and both GaAs and InP devices developed into highly practical microwave sources during the 1970s. Once again, the importance of high quality single crystal growth is emphasised and the development of several epitaxial growth methods (LPE, VPE, MOVPE and MBE) led to the introduction of heterostructures. An important section covers the range of characterisation methods specially developed for the III-V materials.

During the 1970s, III-V compounds and epitaxial crystal growth provided the basis for low dimensional structures (or nanostructures). The best known example is a GaAs quantum well within AlGaAs barriers, electrons, and holes being confined in well defined energy levels that determine the optical properties. Quantum wires and dots are also described. The quantum well laser and the vertical cavity laser (VCSEL) show considerable advantages over their heterostructure predecessor. Another exciting development was that of the two-dimensional electron gas (2DEG) at an interface between semiconductors with different band gaps. By doping only the wide gap material so as to separate the doping atoms from the resulting free electrons, ionised impurity scattering can be minimised and extremely high electron mobilities achieved. Such samples led to the discovery of the fractional quantum Hall effect and to high mobility FETs (HEMTs) for microwave applications. Mesoscopic systems and heterojunction bipolar transistors (HBTs) are also described.

This chapter discusses two important applications of non-single crystal semiconductors: photovoltaic solar cells and large screen liquid crystal display. The electrical and optical properties of polycrystalline and amorphous semiconductors are described. Grain boundaries play a major role in determining the behaviour of polycrystalline materials, acting as energy barriers to current flow and as trapping centres for minority carriers. Grain size and doping levels work together with barrier heights to control material properties. Amorphous materials are characterised by lack of order, but can function as semiconductors with low carrier mobilities. Amorphous silicon, containing hydrogen (aSi:H) is used to make thin film transistors, acting as switches at each pixel point in a LCTV display, thus facilitating matrix addressing. It is also used to make cheap solar cells. Crystalline silicon dominates the commercial field of PV solar cells, but is under challenge from a number of polycrystalline materials, such as CdS:CuInSe.

This chapter investigates the quantum versus classical dynamics of a microwave cavity-coupled-Cooper-pair transistor (CPT) system, where a variable applied dc bias causes the system to tunably self-oscillate via the ac Josephson effect. An essential feature of the system is that the dc bias does not significantly affect the high quality factor of the cavity mode to which the CPT predominantly couples. The classical, nonlinear dynamics of the system exhibits chaotic, as well as aperiodic motions depending on the initial conditions and the nature and strengths of the damping/noise forces. The corresponding quantum dynamics exhibits such phenomena as dynamical tunnelling and the generation of nonclassical states from initial classical states. Obviating the need for an external ac-drive line, which typically is harder to noise filter than a dc bias line, the self-oscillating system described here has considerable promise for demonstrating macroscopic quantum dynamical behaviour.