Semiconductors C. recombination. D. equilibrium. 10. For a forward-biased diode, as temperature is
________, the forward current ________ for a
1. A silicon diode measures a low value of 7. For a forward-biased diode, the barrier
given value of forward voltage.
resistance with the meter leads in both positions. potential ________ as temperature increases.
The trouble, if any, is A. decreased, increases
A. decreases
A. the diode is open. B. increased, increases
B. remains constant
B. the diode is shorted to ground. C. increased, decreases
C. increases
C. the diode is internally shorted. D. decreased, decreases
8. The wide end arrow on a schematic indicates
D. the diode is working correctly. the ________ of a diode. 11. Which statement best describes an insulator?
2. Single-element semiconductors are A. ground A. A material with many free electrons.
characterized by atoms with ____ valence
B. direction of electron flow B. A material doped to have some free electrons.
electrons.
C. cathode C. A material with few free electrons.
A. 3 B. 4 C. 5 D. 2
D. anode D. No description fits.
E. none of the above
9. An n-type semiconductor material 12. Effectively, how many valence electrons are
3. Under normal conditions a diode conducts
there in each atom within a silicon crystal?
current when it is A. is intrinsic.
A. 2 B. 4 C. 8 D. 16
A. reverse-biased. B. forward-biased. B. has trivalent impurity atoms added.
13. The boundary between p-type material and n-
C. avalanched. D. saturated. C. has pentavalent impurity atoms added.
type material is called
4. A diode conducts when it is forward-biased, and D. requires no doping.
A. a diode.
the anode is connected to the ________ through a
limiting resistor. N-type Semiconductor :
B. a reverse-biased diode.
A. positive supply B. negative supply An intrinsic semiconductor material is a poor C. a pn junction.
conductor. When a small amount of pentavalent
C. cathode D. anode D. a forward-biased diode.
impurity is added to the intrinsic material its
5. As the forward current through a silicon diode conductivity rises sharply. This material formed 14. You have an unknown type of diode in a
increases, the internal resistance after the addition of pentavalent impurity to the circuit. You measure the voltage across it and find
intrinsic semiconductor material is called N-type it to be 0.3 V. The diode might be
A. increases. B. decreases.
material. Addition of small amount of
pentavalent atoms in the intrinsic material A. a silicon diode.
C. remains the same.
provides large number of free electrons for B. a germanium diode.
6. The movement of free electrons in a conductor conduction.
is called C. a forward-biased silicon diode.
A. voltage. B. current. D. a reverse-biased germanium diode.
,15. An ideal diode presents a(n) ________ when C. electrons. D. all of the above D. that all impurities are removed to get pure
reversed-biased and a(n) ________ when forward- silicon.
20. Reverse breakdown is a condition in which a
biased.
diode 24. The forward voltage across a conducting
A. open, short B. short, open silicon diode is about
A. is subjected to a large reverse voltage.
C. open, open D. short, short A. 0.3 V. B. 1.7 V.
B. is reverse-biased and there is a small leakage
16. A reverse-biased diode has the ________ current. C. –0.7 V. D. 0.7 V.
connected to the positive side of the source, and
C. has no current flowing at all. 25. The most common type of diode failure is a(n)
the ________ connected to the negative side of
________.
the source. D. is heated up by large amounts of current in the
forward direction. A. open B. short C. resistive
A. cathode, anode
21. There is a small amount of current across the 26. What occurs when a conduction-band electron
B. cathode, base
barrier of a reverse-biased diode. This current is loses energy and falls back into a hole in the
C. base, anode called valence band?
D. anode, cathode A. forward-bias current. A. doping B. recombination C. generation
17. What types of impurity atoms are added to B. reverse breakdown current. 27. The maximum number of electrons in each
increase the number of conduction-band electrons shell of an atom is
C. conventional current.
in intrinsic silicon?
A. 2.
D. reverse leakage current.
A. bivalent B. octavalent
B. 2n2 where n is the number of the shell.
22. As the forward current through a silicon diode
C. pentavalent D. trivalent
increases, the voltage across the diode C. 4.
E. none of the above
A. increases to a 0.7 V maximum. D. 8.
18. What factor(s) do(es) the barrier potential of a
B. decreases. 28. A silicon diode is forward-biased. You measure
pn junction depend on?
the voltage to ground from the anode at
C. is relatively constant.
A. type of semiconductive material ________, and the voltage from the cathode to
D. decreases and then increases. ground at ________.
B. the amount of doping
23. Doping of a semiconductor material means A. 0 V, 0.3 V B. 2.3 V, 1.6 V
C. the temperature
A. that a glue-type substance is added to hold the C. 1.6 V, 2.3 V D. 0.3 V, 0 V
D. all of the above
material together.
E. type of semiconductive material and the amount For silicon diodes, the built-in potential is
B. that impurities are added to increase the approximately 0.7 V. Thus, if an external
of doping but not the temperature
resistance of the material. current is passed through the diode, about
19. An atom is made up of 0.7 V will be developed across the diode such
C. that impurities are added to decrease the
A. protons. B. neutrons. resistance of the material.
that the P-doped region is positive with
, respect to the N-doped region and the diode A. True B. False
is said to be "turned on" as it has a forward
7. An intrinsic crystal is one that contains a small 4. What does a high resistance reading in both
bias.
amount of impurities. forward- and reverse-bias directions indicate?
Therefore, 2.3 V - 1.6 V = 0.7 V. Hence the A. True B. False A. A good diode
answer is correct.
8. N-type semiconductor material has very few B. An open diode
29. The term bias in electronics usually means free electrons.
C. A shorted diode
A. the value of ac voltage in the signal. A. True B. False
D. A defective ohmmeter
B. the condition of current through a pn junction. 9. The silicon material used in semiconductors is
5. Which capacitance dominates in the reverse-
extremely pure with no additives.
C. the value of dc voltages for the device to bias region?
operate properly. A. True B. False
A. depletion
D. the status of the diode. 10. The movement of free electrons in a
B. conversion
semiconductor material is termed electron voltage.
Semiconductor (True or False)
C. 40 Diffusion
A. True B. False
1. A reverse-biased silicon diode has about 0.7 V
D. 140 None of the above
across it. Semiconductor Diodes
6. What is the state of an ideal diode in the region
A. True B. False 1. One eV is equal to ________ J.
of nonconduction?
2. An atom is the smallest particle of an element A. 6.02 × 10^23
A. An open circuit
that retains the characteristics of that element.
B. 1.6 × 10^–19
B. A short circuit
A. True B. False
C. 6.25 × 10^18
C. Unpredictable
3. An intrinsic semiconductor is neither a good
D. 1.66 × 10^–24
conductor nor a good insulator. D. Undefined
2. The diode ________.
A. True B. False 7. How many orbiting electrons does the
A. is the simplest of semiconductor devices germanium atom have?
4. The ideal model of a diode is a switch.
B. has characteristics that closely match those of a A. 4 B. 14 C. 32 D. 41
A. True B. False
simple switch
8. How many terminals does a diode have?
5. A pn structure is called a diode.
C. is a two-terminal device
A. 1 B. 2 C. 3 D. 4
A. True B. False
D. All of the above
9. What unit is used to represent the level of a
6. Forward bias is the condition that allows
3. It is not uncommon for a germanium diode with diode forward current IF?
current through a pn junction.
an Is in the order of 1–2 uA at 25°C to have leakage
A. pA B. nA C. A D. mA
A. True B. False current of 0.1 mA at a temperature of 100°C.
________, the forward current ________ for a
1. A silicon diode measures a low value of 7. For a forward-biased diode, the barrier
given value of forward voltage.
resistance with the meter leads in both positions. potential ________ as temperature increases.
The trouble, if any, is A. decreased, increases
A. decreases
A. the diode is open. B. increased, increases
B. remains constant
B. the diode is shorted to ground. C. increased, decreases
C. increases
C. the diode is internally shorted. D. decreased, decreases
8. The wide end arrow on a schematic indicates
D. the diode is working correctly. the ________ of a diode. 11. Which statement best describes an insulator?
2. Single-element semiconductors are A. ground A. A material with many free electrons.
characterized by atoms with ____ valence
B. direction of electron flow B. A material doped to have some free electrons.
electrons.
C. cathode C. A material with few free electrons.
A. 3 B. 4 C. 5 D. 2
D. anode D. No description fits.
E. none of the above
9. An n-type semiconductor material 12. Effectively, how many valence electrons are
3. Under normal conditions a diode conducts
there in each atom within a silicon crystal?
current when it is A. is intrinsic.
A. 2 B. 4 C. 8 D. 16
A. reverse-biased. B. forward-biased. B. has trivalent impurity atoms added.
13. The boundary between p-type material and n-
C. avalanched. D. saturated. C. has pentavalent impurity atoms added.
type material is called
4. A diode conducts when it is forward-biased, and D. requires no doping.
A. a diode.
the anode is connected to the ________ through a
limiting resistor. N-type Semiconductor :
B. a reverse-biased diode.
A. positive supply B. negative supply An intrinsic semiconductor material is a poor C. a pn junction.
conductor. When a small amount of pentavalent
C. cathode D. anode D. a forward-biased diode.
impurity is added to the intrinsic material its
5. As the forward current through a silicon diode conductivity rises sharply. This material formed 14. You have an unknown type of diode in a
increases, the internal resistance after the addition of pentavalent impurity to the circuit. You measure the voltage across it and find
intrinsic semiconductor material is called N-type it to be 0.3 V. The diode might be
A. increases. B. decreases.
material. Addition of small amount of
pentavalent atoms in the intrinsic material A. a silicon diode.
C. remains the same.
provides large number of free electrons for B. a germanium diode.
6. The movement of free electrons in a conductor conduction.
is called C. a forward-biased silicon diode.
A. voltage. B. current. D. a reverse-biased germanium diode.
,15. An ideal diode presents a(n) ________ when C. electrons. D. all of the above D. that all impurities are removed to get pure
reversed-biased and a(n) ________ when forward- silicon.
20. Reverse breakdown is a condition in which a
biased.
diode 24. The forward voltage across a conducting
A. open, short B. short, open silicon diode is about
A. is subjected to a large reverse voltage.
C. open, open D. short, short A. 0.3 V. B. 1.7 V.
B. is reverse-biased and there is a small leakage
16. A reverse-biased diode has the ________ current. C. –0.7 V. D. 0.7 V.
connected to the positive side of the source, and
C. has no current flowing at all. 25. The most common type of diode failure is a(n)
the ________ connected to the negative side of
________.
the source. D. is heated up by large amounts of current in the
forward direction. A. open B. short C. resistive
A. cathode, anode
21. There is a small amount of current across the 26. What occurs when a conduction-band electron
B. cathode, base
barrier of a reverse-biased diode. This current is loses energy and falls back into a hole in the
C. base, anode called valence band?
D. anode, cathode A. forward-bias current. A. doping B. recombination C. generation
17. What types of impurity atoms are added to B. reverse breakdown current. 27. The maximum number of electrons in each
increase the number of conduction-band electrons shell of an atom is
C. conventional current.
in intrinsic silicon?
A. 2.
D. reverse leakage current.
A. bivalent B. octavalent
B. 2n2 where n is the number of the shell.
22. As the forward current through a silicon diode
C. pentavalent D. trivalent
increases, the voltage across the diode C. 4.
E. none of the above
A. increases to a 0.7 V maximum. D. 8.
18. What factor(s) do(es) the barrier potential of a
B. decreases. 28. A silicon diode is forward-biased. You measure
pn junction depend on?
the voltage to ground from the anode at
C. is relatively constant.
A. type of semiconductive material ________, and the voltage from the cathode to
D. decreases and then increases. ground at ________.
B. the amount of doping
23. Doping of a semiconductor material means A. 0 V, 0.3 V B. 2.3 V, 1.6 V
C. the temperature
A. that a glue-type substance is added to hold the C. 1.6 V, 2.3 V D. 0.3 V, 0 V
D. all of the above
material together.
E. type of semiconductive material and the amount For silicon diodes, the built-in potential is
B. that impurities are added to increase the approximately 0.7 V. Thus, if an external
of doping but not the temperature
resistance of the material. current is passed through the diode, about
19. An atom is made up of 0.7 V will be developed across the diode such
C. that impurities are added to decrease the
A. protons. B. neutrons. resistance of the material.
that the P-doped region is positive with
, respect to the N-doped region and the diode A. True B. False
is said to be "turned on" as it has a forward
7. An intrinsic crystal is one that contains a small 4. What does a high resistance reading in both
bias.
amount of impurities. forward- and reverse-bias directions indicate?
Therefore, 2.3 V - 1.6 V = 0.7 V. Hence the A. True B. False A. A good diode
answer is correct.
8. N-type semiconductor material has very few B. An open diode
29. The term bias in electronics usually means free electrons.
C. A shorted diode
A. the value of ac voltage in the signal. A. True B. False
D. A defective ohmmeter
B. the condition of current through a pn junction. 9. The silicon material used in semiconductors is
5. Which capacitance dominates in the reverse-
extremely pure with no additives.
C. the value of dc voltages for the device to bias region?
operate properly. A. True B. False
A. depletion
D. the status of the diode. 10. The movement of free electrons in a
B. conversion
semiconductor material is termed electron voltage.
Semiconductor (True or False)
C. 40 Diffusion
A. True B. False
1. A reverse-biased silicon diode has about 0.7 V
D. 140 None of the above
across it. Semiconductor Diodes
6. What is the state of an ideal diode in the region
A. True B. False 1. One eV is equal to ________ J.
of nonconduction?
2. An atom is the smallest particle of an element A. 6.02 × 10^23
A. An open circuit
that retains the characteristics of that element.
B. 1.6 × 10^–19
B. A short circuit
A. True B. False
C. 6.25 × 10^18
C. Unpredictable
3. An intrinsic semiconductor is neither a good
D. 1.66 × 10^–24
conductor nor a good insulator. D. Undefined
2. The diode ________.
A. True B. False 7. How many orbiting electrons does the
A. is the simplest of semiconductor devices germanium atom have?
4. The ideal model of a diode is a switch.
B. has characteristics that closely match those of a A. 4 B. 14 C. 32 D. 41
A. True B. False
simple switch
8. How many terminals does a diode have?
5. A pn structure is called a diode.
C. is a two-terminal device
A. 1 B. 2 C. 3 D. 4
A. True B. False
D. All of the above
9. What unit is used to represent the level of a
6. Forward bias is the condition that allows
3. It is not uncommon for a germanium diode with diode forward current IF?
current through a pn junction.
an Is in the order of 1–2 uA at 25°C to have leakage
A. pA B. nA C. A D. mA
A. True B. False current of 0.1 mA at a temperature of 100°C.
