Question

An external voltage \( V \) is supplied to a semiconductor diode having built-in potential \( V_0 \). The effective barrier height under forward bias is

• A. \( V_0 + V \)
• B. \( \frac{V_0 + V}{2} \)
• C. \( V_0 - V \)
• D. \( \frac{V_0 - V}{2} \)
• E. \( 2V_0 + V \)

Hint:

The effective barrier height in a diode decreases with an increase in the forward bias voltage.

Answer 1

The Correct Option is C

The effective barrier height of a diode under forward bias is given by the difference between the built-in potential \( V_0 \) and the applied forward voltage \( V \). This is because the external voltage reduces the potential barrier for the current to flow.
Therefore, the effective barrier height \( V_{{eff}} \) under forward bias is: \[ V_{{eff}} = V_0 - V \] Thus, the correct answer is \( V_0 - V \).