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Electrical Properties of Metals and Semiconductors
Published in Yip-Wah Chung, Monica Kapoor, Introduction to Materials Science and Engineering, 2022
Consider silicon at room temperature doped with 5 × 1016 phosphorus (group V element) atoms/cm3 and 2 × 1016 boron (group III element) atoms/cm3. Assume all impurity atoms are ionized. Is this an n- or p-type semiconductor? What is the approximate carrier concentration?
An Introduction to Crystal Structures
Published in Elaine A. Moore, Lesley E. Smart, Solid State Chemistry, 2020
Elaine A. Moore, Lesley E. Smart
In the last section, we noted that many ‘ionic’ compounds in fact possess some degree of covalency in their bonding. As the formal charge on an ion becomes greater, we expect the degree of covalency to increase, and so we would generally expect compounds of elements in the centre of the periodic table to be covalently bonded. Indeed, some of these elements themselves are covalently bonded solids at room temperature. Examples include elements such as Group 3, boron; Group 14, carbon, silicon, and germanium; Group 15, phosphorus and arsenic; and Group 16, selenium and tellurium, which form extended covalent arrays in their crystal structures.
Semiclassical Principles of Atomic and Molecular Spectra
Published in Leon J. Radziemski, Richard W. Solarz, Jeffrey A. Paisner, Laser Spectroscopy and Its Applications, 2017
The boron group of elements also exhibit doublet and triplet fine- structure transitions. This group has one p electron outside a filled s subshell, so that the ground state will be a fine-structure split pair of levels.
Future of photovoltaic materials with emphasis on resource availability, economic geology, criticality, and market size/growth
Published in CIM Journal, 2023
G. J. Simandl, S. Paradis, L. Simandl
Gallium is a metal with atomic number 31 and atomic weight of 69.732. It is part of group 13 (Boron group) of the periodic table; it sits below Al, above In, to the right of Zn, and to the left of Ge. Its physical properties are similar to those of Al and In. Gallium is considered nontoxic in its elemental form and despite its low melting point (29.76 °C), it is safe to handle. Nevertheless, some Ga compounds are mildly toxic, and others are corrosive (e.g., gallium chloride). For an in-depth review of its toxicity and potential impacts on the environment, see Jabłońska-Czapla and Grygoyć (2021), Nguyen et al. (2020), and Nkuissi et al. (2020).