Semiconductors

Question 1

A semiconductor atom, such as silicon, contains how many valence electrons?

Answer 1

4

Question 2

What is the name given to semiconductor materials that are doped with:

A- Trivalent impurity atoms?
B - Pentavalent impurity atoms?

Answer 2

A - P-type (positive)
B - N-type ( Negative)

Doped: Doping is the process of adding certain elements (impurities) to a semiconductor. Then it becomes DIODE; the electricity go in one-direction.

Question 3

A semiconductor material exhibits a ‘Negative temperature of resistance’. What does it mean?

Answer 3

As temperature increases, their resistance decreases so the conductivity increases.

E = IR

Question 4

What is the typical voltage drop expected across a silicon diode that is conducting in the FORWARD direction?

Answer 4

0,7Volts

Question 5

What does the term PIV mean?

Answer 5

Peak Inverse Voltage

PIV or Peak Reverse Voltage refer to the maximum voltage a diode can withstand in the reverse-biased direction before breakdown.

Question 6

List the leads of the diode symbol

Answer 6

• Cathode ( - ); N-Type
• Anode ( + ); P-Type

Question 7

In order to conduct, the polarity of the cathode must be X with respect to the anode

Answer 7

Negative

Question 8

When using an ohmmeter for testing a diode, what indication would you expect ( high or low) if the diode is:

A - Shorted
B - Open
C - Good

Answer 8

A - Low in both directions
B - High in both directions
C - Low in forward bias and high in reverse bias