The diode’s V-I characteristic curve demonstrates rectification: it allows current to flow easily in the forward direction and blocks it in the reverse direction.
The V-I characteristics of a diode have the following shape:
(A) In the forward bias region, when the applied voltage exceeds the threshold (typically 0.7 V for silicon), the current increases exponentially with increasing voltage.
(B) In the reverse bias region, the current remains very small (ideally zero) until the reverse breakdown voltage is reached.
The graph shows an exponential rise in current in the forward bias region and an almost flat response in the reverse bias region (until breakdown).
