(i) Forward Bias: In this arrangement the positive terminal of battery is connected to p-end and negative terminal to n-end of the crystal, so that an external electric field E is established directed from p to n-end to oppose the internal field Ei as shown in Fig. The external field E is much stronger than internal field Ei
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Reverse Bias: In this arrangement the positive terminal of battery is connected to n-end and negative terminal to p-end of the crystal, so that the external field is established to help the internal field Ei as shown in Fig. Under the biasing the holes in p-region and the electrons in n-region are pushed away from the junction to widen the depletion layer and hence increases the potential barrier, therefore the current flow stops.
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(ii) V-I Characteristics of (a) forward bias and (b) reverse bias:
![](https://www.sarthaks.com/?qa=blob&qa_blobid=13580918756563833494)