In a semiconductor, electrons and holes move in opposite directio… - Vidyadip

Question

In a semiconductor, electrons and holes move in opposite directions to each other. How? Explain with figure.

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Answer

In a semiconductor, some electrons excited by receiving thermal energy at room temperature and transition from the valence band to the conduction band. The empty space created due to the departure of the electron is called 'hole'. The hole behaves like a positively charged particle.
(i) When the electron transitions from the covalent bond postion A, the electron located at another covalent bond position B makes the transition towards the hole created by absorbing thermal energy. With this the hole reaches from A to B.

(ii) The hole reaches C when the electron at B position transitions to another position C. Hence, in this way the electron transitions in the CBA direction and the hole in the ABC direction. In this way the hole and electron move in opposite directions.

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