Semiconductor Electronics: Materials, Devices and Simple Circuits MCQs for NEET — Physics Questions with Answers

In a semiconductor diode, the barrier potential offers opposition to the majority carriers in both regions. In the N region, the majority carriers are electrons, and in the P region, the majority carriers are holes. The barrier potential prevents these majority carriers from diffusing across the junction, maintaining the depletion region.

In a Zener diode, at the breakdown voltage (V_Z), a large change in current produces an insignificant change in the voltage. This is known as the Zener effect, where the diode maintains a nearly constant voltage despite variations in the current, making it useful for voltage regulation applications.

The zener voltage of a zener diode is primarily determined by the level of doping in the semiconductor material. By changing the doping concentration, the breakdown voltage, and hence the zener voltage, can be set to a desired value. Adjusting the input voltage or current, or connecting a resistance in series, are not methods to set the zener voltage.

excess of one valence electron in P atom over Si will form n type conductor.

If trivalent impurity added to the pure semiconductor, then a p-type semiconductor is formed. In a p-type semiconductor, the majority charge carriers are holes and the minority charge carriers are electrons.

In F.B., p-region is at higher potential and n-region is to be at the lower potential.

In n-type semiconductors, majority charge carriers are the electrons and minority charge carriers are holes when the pentavalent impurity is mixed into the pure semiconductor.

2.  ${{\mathrm{n}}_{\mathrm{i}}}^2 = {\mathrm{n}}_{\mathrm{e}}{\mathrm{n}}_{\mathrm{h}}$

$$\begin{gathered} \left(4\right) \\ \mathrm{Conductivity} \mathrm{of} \mathrm{a} \mathrm{semiconductor} \mathrm{is} \\ \mathrm{s} = \mathrm{e}\left[{\mathrm{n}}_{\mathrm{e}}{\mathrm{m}}_{\mathrm{e}} + {\mathrm{n}}_{\mathrm{h}}{\mathrm{m}}_{\mathrm{h}}\right] \end{gathered}$$