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Question
A p-type semiconductor is
Options
positively charged
negatively charged
uncharged
uncharged at O K but charged at higher temperatures.
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Solution
uncharged
A p-type semiconductor is formed by doping a pure semiconductor with a p-type material. As impurity atoms take the position of the germanium atom in a germanium crystal, three electrons of a p-type material form covalent bonds by sharing electrons with three neighbouring germanium atoms. However, the fourth covalent bond is left incomplete, with a want of one electron. This creates a hole. As the atom as a whole is neutral, the p-type material is also neutral.
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