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Question
Can the potential barrier across a p-n junction be measured by simply connecting a voltmeter across the junction?
Solution
We cannot measure the potential barrier across a p-n junction by a voltmeter because the resistance of the voltmeter is very high compared to the junction resistance. Potential of potential barrier for Ge is VB = 0.3 V and for silicon is VB = 0.7 V.
On average the potential barrier in the P-N junction is ~0.5 V.
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