|
Chapter 1: Electric Charges and Fields
|
Chapter 2: Electrostatic Potential and Capacitance
|
|
Chapter 3: Current Electricity
|
Chapter 4: Moving Charges and Magnetism
|
|
Chapter 5: Magnetism and Matter
|
Chapter 6: Electromagnetic Induction
|
|
Chapter 7: Alternating Current
|
Chapter 8: Electromagnetic Waves
|
|
Chapter 9: Ray Optics and Optical Instruments
|
Chapter 10: Wave Optics
|
|
Chapter 11: Dual Nature of Radiation and Matter
|
Chapter 12: Atoms
|
|
Chapter 13: Nuclei
|
Chapter 15: Communication Systems
|
|
1.
|
In the energy-band diagram of n-type Si, the gap between the bottom of the conduction band EC and the donor energy level ED is of the order of:
(a) 10 eV (b) 1 eV (c) 0.1 eV (d) 0.01 eV
|
|
2.
|
Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:
Assertion (A): In insulators, the forbidden gap is very large.
Reason (R): The valence electrons in an atom of an insulator are very tightly bound to the nucleus.
(a) Both Assertion (A) and Reason (R) are true and (R) is the correct explanation of (A).
(b) Both Assertion (A) and Reason (R) are true and (R) is NOT the correct explanation of (A).
(c) Assertion (A) is true and Reason (R) is false.
(d) Assertion (A) is false and Reason (R) is also false.
|
|
3.
|
At 0 K, the resistivity of an intrinsic semiconductor is:
(a) same as that at 0° C (b) same as that at 300 K
(c) zero (d) infinite
|
|
4.
|
When an intrinsic semiconductor is doped with a small amount of trivalent impurity, then:
(a) its resistance increases.
(b) it becomes a p-type semiconductor.
(c) there will be more free electrons than holes in the semiconductor.
(d) dopant atoms become donor atoms.
|
|
5.
|
At a certain temperature in an intrinsic semiconductor, the electrons and holes concentration is 1·5 × 1016 m–3. When it is doped with a trivalent dopant, hole concentration increases to 4·5 × 1022 m–3. In the doped semiconductor, the concentration of electrons (ne) will be:
(a) 3 × 106 m–3 (b) 5 × 107 m–3 (c) 5 × 109 m–3 (d) 6·75 × 1038 m–3
|
|
1.
|
Draw energy band diagram for an n-type and p-type semiconductor at 𝑇 > 0 𝐾.
(CBSE 2023, 2M)
|
|
2.
|
What is meant by energy band gap in a solid? Draw the energy band diagrams for a conductor, an insulator and a semiconductor.
(CBSE 2022, 2M)
|
|
3.
|
(a) Explain the formation of energy bands in crystalline solids.
(b) Draw the energy band diagrams of (i) a metal and (ii) a semiconductor.
(CBSE 2020, 2M)
|
|
4.
|
Draw energy band diagrams of n-type and p-type semiconductors at temperature T > 0K, depicting the donor and acceptor energy levels. Mention the significance of these levels.
(CBSE 2022, 2M)
|
|
5.
|
What is meant by doping of an intrinsic semiconductor? Name the two types of atoms used for doping of Ge/Si.
(CBSE 2022, 2M)
|
|
Chemistry
|
Biology
|
|
Mathematics
|
Physical Education
|
|
Chapter Name
|
Sub Topics of Chapter 14: Semiconductor Electronics
|
|
Semiconductor Electronics
|
14.1 Introduction
|
|
14.2 Classification of Materials
|
|
|
14.3 Intrinsic and Extrinsic Semiconductors
|
|
|
14.4 p-n Junction Diode
|
|
|
14.5 Junction Diode as a Rectifier
|
|
|
14.6 Special Purpose Diodes
|
|
|
14.7 Transistors
|
|
|
14.8 Logic Gates
|
