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A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010
cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure is
- a)1020cm−6
- b)2×1020cm−6
- c)1032cm−6
- d)2×1032cm−6
Correct answer is option 'D'. Can you explain this answer?
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Most Upvoted Answer
A bar of silicon is doped with boron concentration of 1016 cm-3 and a...
Given data:
- Boron concentration, N_B = 10^16 cm^-3
- Rate of electron-hole pairs generation, G = 10^20 cm^-3 s^-1
- Recombination lifetime, τ = 100 μs
- Intrinsic carrier concentration, ni = 10^10 cm^-3
To find: The product of steady-state electron and hole concentration due to the light exposure.
Calculation:
1. Firstly, we need to find the excess carrier concentration due to the light exposure. The excess carrier concentration is given by:
Δn = Δp = Gτ
Δn = Δp = 10^20 cm^-3 s^-1 x 100 μs
Δn = Δp = 10^16 cm^-3
2. Now, we need to find the steady-state carrier concentration. The steady-state carrier concentration is given by:
n*p = ni^2exp(Eg/2kT)
where Eg is the bandgap energy of silicon, k is Boltzmann's constant, and T is the temperature.
3. Since the bar is fully ionized, the doping concentration can be added to the intrinsic concentration:
n_i = N_D + n_i = N_B + n_i
n_i = 10^16 cm^-3 + 10^10 cm^-3 = 10^16 cm^-3
4. Substituting the values in the equation of steady-state carrier concentration:
n*p = (10^16 cm^-3)^2exp(1.12 eV/2kT)
5. Since we are not given the temperature of the silicon bar, we assume room temperature, T = 300 K.
n*p = (10^16 cm^-3)^2exp(1.12 eV/2k(300 K))
n*p = 2.56 x 10^32 cm^-6
Therefore, the approximate product of steady-state electron and hole concentration due to this light exposure is 2 x 10^32 cm^-6, which is option D.
- Boron concentration, N_B = 10^16 cm^-3
- Rate of electron-hole pairs generation, G = 10^20 cm^-3 s^-1
- Recombination lifetime, τ = 100 μs
- Intrinsic carrier concentration, ni = 10^10 cm^-3
To find: The product of steady-state electron and hole concentration due to the light exposure.
Calculation:
1. Firstly, we need to find the excess carrier concentration due to the light exposure. The excess carrier concentration is given by:
Δn = Δp = Gτ
Δn = Δp = 10^20 cm^-3 s^-1 x 100 μs
Δn = Δp = 10^16 cm^-3
2. Now, we need to find the steady-state carrier concentration. The steady-state carrier concentration is given by:
n*p = ni^2exp(Eg/2kT)
where Eg is the bandgap energy of silicon, k is Boltzmann's constant, and T is the temperature.
3. Since the bar is fully ionized, the doping concentration can be added to the intrinsic concentration:
n_i = N_D + n_i = N_B + n_i
n_i = 10^16 cm^-3 + 10^10 cm^-3 = 10^16 cm^-3
4. Substituting the values in the equation of steady-state carrier concentration:
n*p = (10^16 cm^-3)^2exp(1.12 eV/2kT)
5. Since we are not given the temperature of the silicon bar, we assume room temperature, T = 300 K.
n*p = (10^16 cm^-3)^2exp(1.12 eV/2k(300 K))
n*p = 2.56 x 10^32 cm^-6
Therefore, the approximate product of steady-state electron and hole concentration due to this light exposure is 2 x 10^32 cm^-6, which is option D.
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Community Answer
A bar of silicon is doped with boron concentration of 1016 cm-3 and a...
Given
Boron concentration NA = 1016 cm-3
So, NA = ppo =1016cm-3
Generation Rate Gp = 1020 cm-3s-1
Recombination life time てp = 100 μ sec
Intrinsic carrier concentration n1 =1010 cm-3
Using mass action law under thermal equilibrium
So minority carrier concentration 
when light is not exposed is 104 cm-3 When light exposed,
when light is not exposed is 104 cm-3 When light exposed,So after exposing light, excess carrier concentration is
So after exposing light, under equilibrium,
1. Electrons concentration :
2. Hole concentration :
Thus, product of hole concentration and electron concentration after exposing the light is
Hence, the correct option is (D).
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A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer?
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A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer? for Electronics and Communication Engineering (ECE) 2024 is part of Electronics and Communication Engineering (ECE) preparation. The Question and answers have been prepared according to the Electronics and Communication Engineering (ECE) exam syllabus. Information about A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for Electronics and Communication Engineering (ECE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer?.
A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer? for Electronics and Communication Engineering (ECE) 2024 is part of Electronics and Communication Engineering (ECE) preparation. The Question and answers have been prepared according to the Electronics and Communication Engineering (ECE) exam syllabus. Information about A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for Electronics and Communication Engineering (ECE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer?.
Solutions for A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for Electronics and Communication Engineering (ECE).
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A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer?, a detailed solution for A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer? has been provided alongside types of A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice A bar of silicon is doped with boron concentration of 1016 cm-3 and assumed to be fully ionized. It is exposed to light such that electron-hole pairs are generated throughout the volume of the bar at the rate of 1020 cm-3 s-1. If the recombination lifetime is 100 μs and intrinsic carrier concentration of silicon is 1010cm-3 and assuming 100% ionization of boron, then the approximate product of steady-state electron and hole concentration due to this light exposure isa)1020cm−6b)2×1020cm−6c)1032cm−6d)2×1032cm−6Correct answer is option 'D'. Can you explain this answer? tests, examples and also practice Electronics and Communication Engineering (ECE) tests.
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