Semiconductors and Semiconductor Devices Physics - Semiconductors and Semiconductor Devices

Two identical capacitors A and B are charged to the same potential V and are connected in two circuits at t = 0 as shown in figure. The charges on the capahltors at a time t = CR are, respectively:

• A
  $\text{VC}, \text{VC}$
• ✓
  $\frac{\text{VC}}{\text{e}}, \text{VC}$
• C
  $\text{VC}, \frac{\text{VC}}{\text{e}}$
• D
  $\frac{\text{VC}}{\text{e}}, \frac{\text{VC}}{\text{e}}$

Answer: B.

• A
  The hole concentration increases.
• B
  The hole concentration decreases.
• ✓
  The electron concentration increases.
• D
  The electron concentration decreases.

Answer: C.

• A
  Phosphorus.
• B
  Boron.
• C
  Aluminium.
• ✓
  Both  $B$ and $C$

Answer: D.

• A
  Electrons only.
• B
  Holes only.
• ✓
  Both electrons and holes.
• D
  Neither electrons nor holes.

Answer: C.

• A
  From the n-side to the p-side.
• ✓
  From the p-side to the n-side.
• C
  From the n-side to the p-side if the junction is forward-biased and in the opposite direction if it is reverse-biased.
• D
  From the p-side to the n-side if the junction is forward-biased and in the opposite direction if it is reverse-biased.

Answer: B.

• A
  The emitter has the least concentration of impurity.
• B
  The collector has the least concentration of impurity.
• ✓
  The base has the least concentration of impurity.
• D
  All the three regions have equal concentrations of impurity.

Answer: C.

• A
  'Collector' and 'base'.
• B
  'Base' and 'emitter'.
• C
  'Collector' and 'emitter'.
• ✓
  'Base' and 'base'.

Answer: D.