SOLID STATE DEVICES MCQS Part 6

SOLID STATE DEVICES MCQS Part 6

SOLID STATE DEVICES Multiple Choice Questions Part 6.

1 What term is used to describe the outermost shell of an atom?
Valence shell
Free shell
Electron shell
Conductive cell

2 What are the electrons at the outermost shell which are usually weakly attracted by the core such that an outside force can easily dislodge these electrons from the atom?
Free electrons
Orbiting electrons
Bound electrons
Loose electrons

3 The reason why electrons are not pulled in the positive charged nucleus is because of the which usually became exactly equals the inward attraction of the nucleus.
Kinetic energy
Energy at rest
Centrifugal force
Frictional force

4 Which of the following items is not a type of material?
Conductor
Semiconductor
Insulator
Diode

5 The highest energy band of an atom which can be filled with electrons.
Valence band
Conduction band
Insulation band
Energy level

6 An energy band in which electrons can move freely
Valence band
Conduction band
Energy gap
Insulation gap

7 Approximate energy gap in insulator is
Eg = > 5 eV
Eg = 1.1 eV
Eg = 0.67 eV
Eg = 4 eV

8 The energy gap for semiconductors made of silicon is
Eg = 5 eV
Eg = 1.1 eV
Eg = 0.67 eV
Eg = 4 eV

9 The energy gap for germanium made semiconductor is
Eg = 5 eV
Eg = 1.1 eV
Eg = 0.67 eV
No energy gap

10 What type of material usually has one valence electron?
Insulator
Semiconductor
Conductor
Transistor

11 What type of material usually has four valence electrons?
Insulator
Semiconductor
Conductor
IGFET

12 Which of the following is considered as the best conductor?
Gold
Silicon
Germanium
Mica

13 Which of the items below is not taking place inside a silicon crystal?
Some free electrons and holes are being created by thermal energy
Other free electrons and holes are recombining
Some free electrons and holes exist in an in-between state
Some free electrons disappears in the lattice due to vaporization

14 It is an arrangement of silicon atoms combine to form a solid such that there are now 8 electrons in the valence shell.
Crystal
Bonding
Recombination
Solid silicon

15 The sharing of valence electrons to produce a chemically stable atom
Bound electrons
Crystal
Covalent bond
Recombination

16 The eight electrons which are tightly held by the atom are called
Valence electrons
Outermost electrons
Bound electrons
Covalent electrons

17 When an atom has bound electrons, it is described as
All charges do recombination
Valence electrons disappear due to vaporization
Filled or saturated since valence orbit can hold not more than 8 electrons
Merging of electrons and other particles

18 What refers to the temperature of the surrounding air?
Atmospheric temperature
Ambient temperature
Freezing point
Cooling temperature

19 What term is used to describe the released electrons dislodged from its original
shell due to the increase in temperature which joins into a larger orbit?
Free electrons
Bound electrons
Covalent electrons
Merge electrons

20 What term is used to refer to the vacancy left by the free electron when it departs from its original shell?
Proton
Hole
Neutron
Nucleus

21 The merging of a free electron and a hole inside the silicon crystal
Covalent bond
Recombination
Merged electron
Valence bond

22 The amount of time between the creation and disappearance of a free electron.
Recombination time
Bonding time
Lifetime
Propagation time

23 The purpose of adding an impurity atom to an intrinsic crystal is
To alter its insulating property
To increase its electric conductivity
To stop conduction
To increase the resistivity of the semiconductor material

24 An extrinsic semiconductor produces when a pentavalent atom is added to the molten silicon
Intrinsic
P-type
N-type
Hybrid type

25 Which of the items below is not a pentavalent atom?
Phosphorus
Aluminum
Antimony
Arsenic

26 What extrinsic semiconductor is produced when a trivalent atom is added to the molten silicon?
Aluminum
N-type
P-type
Holes

27 The reduction of power handling capability of the diode due to the increase of ambient temperature form room temperature.
Maximum junction temperature
Linear power derating factor
Power factor
Amplification factor

28 The maximum temperature the diode can operate before burning.
Maximum dissipation factor
Maximum junction temperature
Ambient temperature
Boiling temperature rating

29 Reverse recovery time of the diode is computed as the of the storage time and transition interval from the forward to reverse bias.
Sum
Product
Quotient
Difference

30 The nucleus of a copper atom contains how many protons?
2
1
18
29

31 How many protons does the nucleus of a silicon atom contain?
4
14
29
32

32 An intrinsic semiconductor has some holes in it at room temperature. What causes these holes?
Doping
Thermal energy
Free electrons
Valence electrons

33 When a diode is forward biased, the recombination of free electrons and holes may produce ?
Heat
Light
Radiation
All of the above

34 Which of the following doping elements have a valence of 5?
Gallium
Boron
Aluminum
Phosphorous

35 Which of the following doping elements have a valence of 4?
Arsenic
Gallium
Aluminum
Silicon

36 Which of the following doping elements have a valence of 3?
Gallium
Boron
Aluminum
Phosphorous

37 It is a stable positive charge in the nucleus that is not free to move
Hole
Proton
Neutron
Electron

38 A positive charge outside the nucleus which is present only in semiconductor due to unfilled covalent bonds.
Electron
Proton
Hole
Neutron

39 When charges are forced to move by the electric field of a potential difference,
  current is said to flow.
Reverse
Drift
Leakage
Threshold

40 When PN junction is connected to a battery in such a way that P-side is connected to positive terminal of the battery and negative terminal to N-side, this connections is known as
Forward bias
Reverse bias
Back bias
Knee bias

41 When PN junction is connected to a battery in such a way that P-side is connected to negative terminal of the battery and positive terminal to N-side, this connections is known as
Forward bias
Reverse bias
Depletion connection
Positive bias

42 An electron in the conduction band
Losses its charge easily
Jumps to the tip of the crystal
Has higher energy than the electron in the valence band
Has lower energy that the electron in the valence band

43 An ideal diode
Should have a zero resistance in the forward bias as well as in reverse bias
Should have an infinitely large resistance in the forward bias and zero resistance
in reverse bias
Should have zero resistance in forward bias and an infinitely large resistance in reverse bias
Should have infinitely large resistance in forward as well as reverse bias

44 Thermal voltage Vt is approximately equal to at room temperature (20ºC)
25 mV
25 V
100 mV
100 V

45 Boltzmann’s constant is equivalent to
⦁      1.62 x 10^-18 C
⦁      8032 x 10^-5 eV/ºK
⦁      0.7 V
⦁      1.3 x 10^8 V/m

46 The preferred form of biasing a JFET amplifier is through the
Voltage divider bias
Gate bias
Self bias
Source bias

47 The gate-to0source on voltage if an n-channel enhancement mode MOSFET is
Less than Vth
Equal to Vgs(off)
Greater than VDS(on)
Greater than VGS(th)

48 A full-wave signal has a period of
16.7 µs
8.3 µs
8.3 ms
16.7 ms

49 A mechanism for carrier motion in semiconductors which occurs when an electric field is applied across a piece of silicon
Carrier diffusion
Carrier drift
Recombination
Diffusivity

50 What occurs in pn diodes when the minority carriers that cross the depletion region under the influence of the electric field gain sufficient kinetic energy to be able to break covalent bonds in atoms with which they collide?
Drift
Avalanche breakdown
Diffusion
Saturation

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