Фотоэмиссия свободных носителей заряда в высокоомный полупроводник при освещении омических контактов
The photoemission of free charge carriers into high-ohmic semiconductor created by light illumination of near-contact-area of ohmic contacts to cadmium telluride sample was investigated. It was revealed, that near-contact-area light illumination influences both on contact transition resistance and on volume conductivity of the crystal due to increasing of main charge carrier concentration. The method of separate determination of contact transition and sample volume resistances, suitable for high-ohmic semiconductors, was suggested.
The 6th International Conference State-of-the-art trends of scientific research of artificial and natural nanoobjects continued a series of events that began in 2009. The conference focused on the research of diverse nano-sized or nano-structured objects enabled by advanced microscopy and analytical techniques: high resolution and analytic scanning electron microscopy (SEM), high-resolution transmission electron microscopy, helium ion microscopy, atomic probe microscopy, and combined microscopy-spectroscopy methods. Special attention was made to advanced sample preparation techniques for microscopic investigations as well as to advanced nanofabrication techniques such as nanolithography (e-beam, dedicated ion-beam), focused ion beam-SEM, and driven self-assembly processes. These proceedings collect selected papers that contain novel original results in three specific topical areas: nanofabrication, nanoimaging, and nanophotonics.
The conference is devoted to fundamental problems of semiconductor physics.Main sections of the program: 1. Bulk semiconductors: electrical and optical properties, relaxation of charge carriers, ultrafast phenomena, excitons, phonons, phase transitions, ordering. 2. Surface, films, layers: epitaxy, atomic and electronic structure of the surface, adsorption and surface reactions, processes of formation (self-organization) of nanoclusters, STM and AFM, optical microscopy of the near field. 3. Heterostructures, superlattices, one-dimensional systems: structural and optical properties, electronic transport. 4. Two-dimensional systems: structural, electronic, magnetic and optical properties, tunneling, localization, phonons, plasmons, quantum Hall effect, correlation effects. 5. Zero-dimensional systems (quantum dots, nanocrystals): energy spectrum, optical properties, tunnel transport. 6. Spin phenomena, spintronics, nanomagnetism. 7. Impurities and defects (bulk semiconductors and quantum-dimensional structures): impurities with shallow and deep levels, magnetic impurities, structural defects, disordered semiconductors. 8. High-frequency phenomena in semiconductors (microwave and terahertz range). 9. Carbon and graphene-like nanomaterials, transition metal dichalcogenide monolayers, perovskites, organic semiconductors, molecular systems. 10. Photonic crystals, microresonators and metamaterials. Nanophotonics. 11. Semiconductor devices: technology, research methods, and nanodevices. 12. Nano-and optomechanics. 13. Topological insulators and Weyl semimetals.Выделите текст, чтобы посмотреть примерыДелитесь своими подборкамиСоздавайте подборки переводов для учёбы, работы или просто так и используйте вместе с друзьямиПопробоватьПримерыУстановите приложение на смартфон и работайте офлайн+Установить ПереводчикСообщение отправленоОтправить ещё разПереводите в Яндекс.Браузере
Despite the fact that electron transport in condensed helium has been studied for over half a century , observations of new intriguing effects still appear . Alas, the traditional methods of injecting electrons into condensed helium (radioactive-sources, electrical discharge or field emission) lead to generation of helium ions, recombination of which is accompanied by emergence of a large number of excitations. As a result, interpretation of such experiments is not simple and sometimes may be questionable. In this respect, photoelectron emitters, which operate with energies substantially smaller than the ionization energy of helium, are preferable. However, immersion of the photocathode into condensed helium suppresses electron emission. Nevertheless, we managed to achieve electron currents (>20 fA) with the In photocathode immersed directly in liquid superfluid helium. The UV light (λ=254 nm) was guided to the photocathode through a two-meter long Al-covered quartz optical fiber.
The influence of local illumination providing high level of free charge carrier injection upon semiinsulating cadmium telluride sample conductivity and properties of ohmic contacts to the sample is investigated. It is revealed, that independently upon illumination region the value of ohmic contact transition resistance decreases and main charge carrier concentration increases proportionally illumination intensity. Light probe scanning is shown to be suitable for investigation of intrinsic semiinsulating semiconductor crystal inhomogenuities
It is known that illumination of the sample vysokomnogo semiconductor material significantly changes its electrical properties. It is shown that the contact regions of the sample illumination with monochromatic radiation intensity adjustable with a photon energy greater than the width of the forbidden zone of the test material, reduces the resistance of the sample, in some cases by several orders of magnitude. Provides a method for the separate determination of the resistance of the sample and contacts to it, which has been tested on a sample of semi-insulating n-GaAs. It is shown that the resistance of the sample volume and the total resistance of the contacts are close to each other and equal to about 5 108 ohms.