Exam
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1)
The difference in energy levels that exists between the valence band and the conduction band is
called
1)
A)
energy gap.
B)
covalent gap.
C)
semiconductor region.
D)
spark gap.
Answer:
A
A)
B)
C)
D)
2)
On diode check, a shorted diode will measure
2)
A)
0.7 V.
B)
0.3 V.
C)
0.79 V.
D)
0 V.
Answer:
D
A)
B)
C)
D)
3)
The boundary between p-type material and n–type material in a diode is called
3)
A)
the control grid.
B)
the pn junction.
C)
the cathode.
D)
the anode.
Answer:
B
A)
B)
C)
D)
4)
Valence electrons have ________ energy level of all the electrons in orbit around the nucleus of a
given atom.
4)
A)
the lowest
B)
the same
C)
the highest
D)
None of the above.
Answer:
C
A)
B)
C)
D)
1
5)
Which statement best describes a p-type semiconductor?
5)
A)
Silicon with trivalent impurity atoms added.
B)
A material where holes are the minority carriers.
C)
Silicon with pentavalent impurity.
D)
Pure intrinsic silicon.
Answer:
A
A)
B)
C)
D)
6)
A nonconducting diode is ________ biased.
6)
A)
poorly
B)
reverse
C)
forward
D)
inverse
Answer:
B
A)
B)
C)
D)
7)
Holes are the majority carriers in
7)
A)
a pn junction semiconductor.
B)
an n-type semiconductor.
C)
a p-type semiconductor.
D)
None of the above.
Answer:
C
A)
B)
C)
D)
8)
How much forward diode voltage is there with the ideal–diode approximation?
8)
A)
0 V
B)
More than 0.7 V
C)
1 V
D)
0.7 V
Answer:
A
A)
B)
C)
D)
9)
The valence electron of a copper atom experiences what kind of attraction toward the nucleus?
9)
A)
Strong
B)
None
C)
Weak
D)
Impossible to say
Answer:
C
A)
B)
C)
D)
2
10)
What is the maximum number of electrons that can exist in the shell closest to the nucleus of an
atom?
10)
A)
1
B)
2
C)
4
D)
8
Answer:
B
A)
B)
C)
D)
11)
All of the following are semiconductors except
11)
A)
copper.
B)
germanium.
C)
carbon.
D)
silicon.
Answer:
A
A)
B)
C)
D)
12)
Germanium has limited use in modern electronics due to
12)
A)
filament warm–up time.
B)
high temperature instability.
C)
higher forward voltage drop when compared to Si.
D)
shortages of raw materials.
Answer:
B
A)
B)
C)
D)
13)
Electrons orbiting the nucleus of an atom are grouped into energy bands known as
13)
A)
shells.
B)
tracks.
C)
tunnels.
D)
slots.
Answer:
A
A)
B)
C)
D)
14)
Semiconductor materials are those with
14)
A)
no conductive properties.
B)
conductive properties that are in between those of a conductor or an insulator.
C)
conductive properties that are very good.
D)
Either A or B.
Answer:
B
A)
B)
C)
D)
3
15)
The atomic number of an atom refers to the
15)
A)
number of electrons in a charged atom.
B)
number of neutrons in the nucleus.
C)
net electrical charge of the atom.
D)
number of protons in the nucleus.
Answer:
D
A)
B)
C)
D)
16)
If the positive lead of an ohmmeter is placed on the cathode and the negative lead is placed on the
anode, which of the following readings would indicate a defective diode?
16)
A)
0
B)
C)
400 k
D)
1 M
Answer:
A
A)
B)
C)
D)
17)
Silicon and germanium contain ________ valence electrons.
17)
A)
one
B)
two
C)
four
D)
eight
Answer:
C
A)
B)
C)
D)
18)
A DMM measures 0.13 in both directions when testing a diode. The diode is
18)
A)
open.
B)
constructed of Si and is good.
C)
operating normally.
D)
shorted.
Answer:
D
A)
B)
C)
D)
TRUE/FALSE. Write ‘T’ if the statement is true and ‘F’ if the statement is false.
19)
Silicon doped with impurities is used in the manufacture of semiconductor devices.
19)
Answer:
True
False
20)
A molecule is the smallest particle of an element that retains the characteristics of that element.
20)
Answer:
True
False
21)
The typical barrier potential for germanium is about 0.7 V.
21)
Answer:
True
False
4
22)
Semiconductor material of the p-type has few free electrons.
22)
Answer:
True
False
5