InterviewSolution
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What is a PN-junction diode? What is a depletion region? What is barrier potential in a PN-junction? |
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Answer» PN-junction diode: A two-terminal semiconductor device consisting of a PNjunction is called a PN- junction diode. Depletion region: The neighbourhood of the junction between a p-type layer and an n-type layer within a single semiconducting crystal is depleted of free (or mobile) charge carriers. This is called the depletion region or depletion layer. Barrier potential: The electric potential difference across the PN-junction is called the potential barrier or barrier potential. [Note: Under the open-circuit condition (no applied potential difference), the width of the depletion region and the height of the potential barrier have their equilibrium values. The width of the depletion region in an unbiased pn-junction diode ranges from 0.5 pm to 1 pm and depends on the dopant concentrations. The barrier potential is about 0.3 V for Ge junction diode and about 0.7 V for Si junction diode.] |
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