No, we cannot measure the potential barrier across a p-n junction by simply connecting a voltmeter across the junction because resistance across the junction is almost infinite and no current will flow through the voltmeter.
Class 12 Physics Chapter 14 Semiconductor Electronics Session 2024-2025.
No, the potential barrier across a p-n junction cannot be measured directly using a voltmeter because the depletion region lacks free charge carriers. The voltmeter measures external voltage, but the built-in potential exists internally, preventing direct measurement without disturbing the junction equilibrium.
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