The manifestation of band structure in solids is due to

• Heisenberg’s uncertainty principle

• Pauli’s exclusion principle

• Bohr’s correspondence principle

• Bohr’s correspondence principle

When p-n junction diode is forward biased

• the depletion region is reduced and barrier height is increased

• the depletion region is widened and barrier height is reduced.

• both the depletion region and barrier height reducedboth the depletion region and barrier height reduced

• both the depletion region and barrier height reducedboth the depletion region and barrier height reduced

In an insulator, band gap of the order of

• 0.1 eV

• 1 eV

• 5 eV

• 100 eV

34.

For a P-N junction diode

• Forward current in mA and reverse current is in µA

• Forward current is in µA are reverse current is in mA

• Both forward and reverse currents are in µA

• Both forward and reverse currents are in mA

For a Zener diode

• both p and n regions are heavily doped

• p region is heavily doped but n region is lightly doped

• n region is heavily doped but p region is lightly doped

• both p and n regions are lightly doped

The electron density of intrinsic semiconductor at room temperature is 10¹⁶ m^-3. When doped with a trivalent impurity, the electron density is decreased to 10¹⁴ m^- at the same temperature. The majority carrier density is

• 10¹⁶ m^-3

• 10¹⁸ m^-3

• 10²¹ m^-3

• 10²⁰ m^-3

In a Zener diode regulated power supply, unregulated DC input of 10 V is applied. If the resistance (R_s) connected in series with a Zener diode is 200 Ω and the Zener voltage V_z =5V, the current across the resistance R_s is

• 15 mA

• 10 mA

• 25 mA

• 5 mA

The circuit gives the output as that

• AND gate

• OR gate

• NAND gate

• NOR gate

To detect light of wavelength 500 nm, the photodiode must be fabricated from a semiconductor of minimum bandwidth of

• 1.24 eV

• 0.62 eV

• 2.48 eV

• 3.2 eV

For which one of the following input combinations, the given logic circuit gives the output Y = 1 ?

• A = 0, B = 0, C = 0

• A = 0, B = 1, C = 0

• A = 0 ,B = 1, C = 1

• A = 1 ,B = 1 ,C = 1