for
Electronics and Communication
Engineers
(PSUs/GATE/IES)
, 1
CHAPTER
MATERIALS AND
COMPONENTS
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1.1 STRUCTURE AND PROPERTIES OF 1 1
ELECTRICAL ENGINEERING MATERIALS x ms ,
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According to Bohr’s theory of the atom crystalline solid and is called the lattice constant d of the crystal.
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En eV;
n2 h2 n2 Principles of Electron Energy Bands
eV electron volt
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trons across the crystal lattice.
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x 7KHHQHUJ\EDQGVWUXFWXUHRIVROLGVSURYLGHVDEDVLVZKLFK and do not pass freely through the crystal. This statement should
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Gallium Arsenide Versus Silicon
Fig. 1.1 x Gallium Arsenide and other compound semiconductors
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number of valence electrons per atom compared to silicon.
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positive ions of crystal atoms and valence-core electron cloud re- compound semiconductor technology till date.
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