Semiconductor Interfaces At The Sub Nanometer Scale

The Advanced Research Workshop on the Physical Properties of Semiconductor Interfaces at the Sub-Nanometer Scale was held from 31 August to 2 September, 1992, in Riva del Garda. Italy. The aim of the workshop was to bring together experts in different aspects of the study of semiconductor interfaces and in small-scale devices where the interface properties can be very significant It was our aim that this would help focus research of the growth and characterization of semiconductor interfaces at the atomic scale on the issues that will have the greatest impact on devices of the future. Some 30 participants from industrial and academic research institutes and from 11 countries contributed to the workshop with papers on their recent wode. . 'There was ample time for discussion after each talk. as well as a summary discussion at the end of the meeting. The major themes of the meeting are described below. The meeting included several talks relating to the different growth techniques used in heteroepitaxial growth of semiconductors. Horikoshi discussed the atomistic processes involved in MBE, MEE and MOCVD, presenting results of experimental RHEED and photoluminescence measurements; Foxon compared the merits of MBE, MOCVD, and eBE growth; Molder described RHEED studies of Si/Ge growth by GSMBE, and Pashley discussed the role of surface reconstructions in MBE growth as seen from STM studies on GaAs. On the theoretical side, Vvedensky described several different methods to model growth: molecular dynamics, Monte Carlo techniques, and analytic modeling.

Optics at the Nanometer Scale: Imaging and Storing with Photonic Near Fields deals with the fundamentals of and the latest developments and applications of near-field optical microscopy, giving basic accounts of how and under what circumstances superresolution beyond the half- wavelength Rayleigh limit is achieved. Interferometric and fluorescence techniques are also described, leading to molecular and even atomic resolution using light. The storage of optical information at this level of resolution is also addressed.

An assessment of the recent achievements and relative strengths of two developing techniques for characterising surfaces at the nanometer scale: (i) local probe methods, including scanning tunnelling microscopy and its derivatives; and (ii) nanoscale photoemission and absorption spectroscopy for chemical analysis. The keynote lectures were delivered by some of the world's best scientists in the field and some of the topics covered include: (1) The possible application of STM in atomically resolved chemical analysis. (2) The principles of scanning force/friction and scanning near-field optical microscopes. (3) The scanning photoemission electron microscopes built at ELETTRA and SRRC, with a description of synchrotron radiation microscopy. (4) Recent progress in the development of spatially-resolved photoelectron microscopy, especially the use of zone plate photon optics. (5) The present status of non-scanning photoemission microscopy with slow electrons. (6) the BESSY 2 project for a non-scanning photoelectron microscope with electron optics. (7) Spatially-resolved in situ reaction studies of chemical waves and oscillatory phenomena with the UV photoemission microscope.

This book reviews the recent advances and current technologies used to produce microelectronic and optoelectronic devices from compound semiconductors. It provides a complete overview of the technologies necessary to grow bulk single-crystal substrates, grow hetero-or homoepitaxial films, and process advanced devices such as HBT's, QW diode lasers, etc.

Nanoscale Probes of the Solid--Liquid Interface deals with the use of the scanning tunnelling microscope (STM) and related instrumentation to examine the phenomena occurring at the interface between solid and liquid. Scanning probe microscopy (the collective term for such instruments as the STM, the atomic force microscope and related instrumentation) allows detailed, real space atomic or lattice scale insight into surface structures, information which is ideally correlated with surface reactivity. The use of SPM methods is not restricted to ultrahigh vacuum: the STM and AFM have been used on samples immersed in solution or in ambient air, thus permitting a study of environmental effects on surfaces. At the solid--liquid interface the reactivity derives precisely from the presence of the solution and, in many cases, the application of an external potential. Topics covered in the present volume include: the advantages of studying the solid--liquid interface and the obtaining of additional information from probe measurements; interrelationships between probe tip, the interface and the tunnelling process; STM measurements on semiconductor surfaces; the scanning electrochemical microscope, AFM and the solid--liquid interface; surface X-ray scattering; cluster formation on graphite electrodes; Cu deposition on Au surfaces; macroscopic events following Cu deposition; deposition of small metallic clusters on carbon; overpotential deposition of metals; underpotential deposition; STM on nanoscale ceramic superlattices; reconstruction events on Au(ijk) surfaces; Au surface reconstructions; friction force measurements on graphite steps under potential control; and the biocompatibility of materials.

The articles in this book have been selected from the lectures of a NATO Advanced Study Institute held at Bad Lauterberg (Germany) in August 1995. Internationally well-known researchers in the field of mesoscopic quantum physics provide insight into the fundamental physics underlying the mesoscopic transport phenomena in structured semiconductor inversion layers. In addition, some of the most recent achievements are reported in contributed papers. The aim of the volume is not to give an overview over the field. Instead, emphasis is on interaction and correlation phenomena that turn out to be of increasing importance for the understanding of the phenomena in the quantum Hall regime, and in the transport through quantum dots. The present status of the quantum Hall experiments and theory is reviewed. As a "key example" for non-Fermi liquid behavior the Luttinger liquid is introduced, including some of the most recent developments. It is not only of importance for the fractional quantum Hall effect, but also for the understanding of transport in quantum wires. Furthermore, the chaotic and the correlation aspects of the transport in quantum dot systems are described. The status of the experimental work in the area of persistent currents in semiconductor systems is outlined. The construction of one of the first single-electron transistors is reported. The theoretical approach to mesoscopic transport, presently a most active area, is treated, and some aspects of time-dependent transport phenomena are also discussed.

Contributed papers of the workshop held at IIT, Madras, in 2003.

Nanoscale Science, whose birth and further growth and development has been driven by the needs of the microelectronics industry on one hand, and by the sheer human curiosity on the other hand, has given researchers an unprecedented capability to design and construct devices whose function ality is based on quantum and mesoscopic effects. A necessary step in this process has been the development of reliable fabrication techniques in the nanometer scale: two-dimensional systems, quantum wires and dots, and Coulomb blockade structures with almost ideal properties can nowadays be fabricated, and subjected to experimental studies. How does one fabricate micro/nanostructures of low dimensionality? How does one perform a nanoscale characterization of these structures? What are the fundamental properties typical to the structures? Which new physical processes in nanostructures need to be understood? What new physical processes may allow us to create new nanostructures? An improved understanding of these topics is necessary for creation of new concepts for future electronic and optoelectronic devices and for characterizing device structures based on those concepts.