Electronic Devices Tutorial 0

HORMUD UNIVERSITY

Electronic Devices

Tutorial 0

Energy Band

1. State two types of energy band.

Material Classification (Insulators, Conductors, and Semiconductors)

1. Sketch the energy diagram for insulator, semiconductor and conductor.

2. What type of atom has four valence electrons?

3. (a) How does a silicon crystal formed?

(b) How many covalent bonds does a single atom form?

4. What is an intrinsic crystal?

Current in Semiconductors

1. What do you understand by electron-hole pair?

2. What is the difference between electron current and hole current?

3. Which energy level does hole current occur?

4. What happens when silicon is exposed to heat.

n-Type and p-Type Semiconductors

1. What is doping?

2. a) Give one example of pentavalent and trivalent impurity, respectively.

b) Sketch the atom structure diagram of the given example in forming N-type and P-

type semiconductor.