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Origins
Published in Douglas S. McGregor, J. Kenneth Shultis, Radiation Detection, 2020
Douglas S. McGregor, J. Kenneth Shultis
Although Ge and Si have been established as important radiation detectors, the need for cryogenic cooling is inconvenient, especially in situations where a portable device is required. Hence, the search for semiconductor devices that can operate at room temperature remains a priority. Detectors made from gallium arsenide (GaAs), a wide band-gap semiconductor that can be operated at room temperature, were studied and reported as radiation counters in 1960. In 1970, Eberhardt, Ryan, and Tavendale demonstrated the first high energy resolution semiconductor room-temperature-operated gamma-ray spectrometer. The detector was fabricated from a high-purity, epitaxially grown GaAs crystal, and the active region of the device was only 80 microns thick. Since then, many other, and perhaps more promising, semiconductors have been studied. These include mercuric iodide, cadmium telluride, and cadmium zinc telluride. The main impediment to widespread use of compound semiconductors is the difficulty of producing quality detector crystals. It is much harder to produce defect-free compound semiconductors than it is to produce defect-free single-element semiconductors, of which only Si and Ge are practical materials.12
Literature review
Published in Joyabrata Mal, Microbial Synthesis of Chalcogenide Nanoparticles, 2018
Te is a P (positive)-type semiconductor and has unique optical and electrical properties. It is an important component in industrial steels, glasses and solar panels (Turner et al., 2012). In the last decade, research on Te has gained considerable interest due to the development of fluorescent CdTe quantum dots with a high quantum yield for in vivo cell imaging applications (Deng et al., 2007). A significant amount of research has recently been focused on telluride clusters and nanoparticles as an important tool for new solar cell technology and in biomedicine (Wachter, 2004; Zhang et al., 2007). Te has no known function in living systems. But, microorganisms are involved in the biotransformation of Te oxyanions to insoluble elemental tellurium (Te(0)) or telluride (Te(-II)) (Turner et al., 2012). This bioreduction can be useful in bioremediation efforts of Te polluted wastewaters or soils and couple it to heavy metal removal via metal telluride (MeTe) formation.
2 Zeroth-Level Packaging Materials
Published in Mitel G. Pecht, Rakesh Agarwal, Patrick McCluskey, Terrance Dishongh, Sirus Javadpour, Rahul Mahajan, Electronic Packaging: Materials and Their Properties, 2017
Mitel G. Pecht, Rakesh Agarwal, Patrick McCluskey, Terrance Dishongh, Sirus Javadpour, Rahul Mahajan
Tellurides or tellurium compounds, including CdTe, ZnTe, CdZnTe, and CdHgTe, are direct-bandgap II-VI semiconductor materials that are useful in a wide variety of electronic and optoelectronic devices ranging from near ultraviolet to far infrared detectors.
Pulsed current-voltage electrodeposition of stoichiometric Bi2Te3 nanowires and their crystallographic characterization by transmission electron backscatter diffraction
Published in Science and Technology of Advanced Materials, 2019
Cristina V. Manzano, Mikhail N. Polyakov, Jon Maiz, Myriam H. Aguirre, Xavier Maeder, Marisol Martín-González
Bismuth telluride is an attractive semiconductor whose principal application is as a thermoelectric material around room temperature. Moreover, Bi2Te3 belongs to a novel class of quantum materials called three-dimensional topological insulators (3D-TIs) [1,2]. This quantum form of matter presents unique and topologically protected surface states [3–6]. Therefore, in order to study these effects and the possible relations between them, it is important to synthesize Bi2Te3 nanowires of high crystallographic quality. The thermoelectric figure of merit of nanowires can be increased by lattice thermal conductivity [7,8]. The reduction of this parameter is achieved by the reduction of the size of the nanostructure due to the increment of the phonon scattering, through the reduction of the diameter in the case of the nanowires.
Improving the thermoelectric figure of merit
Published in Science and Technology of Advanced Materials, 2021
One of the best ways of reducing the lattice thermal conductivity is the formation of a solid solution [6]. For example, the compound lead telluride is a useful thermoelectric generator material. Its figure of merit can be further improved by alloying it with the isomorphous compounds lead selenide or tin telluride. The disturbance of the short range order is effective in scattering phonons but the maintenance of the long range order means that the carrier mobility is unaffected.