A semiconductor sample at room temperature has intrinsic concentratio...
In a pure Semiconductor (Intrinsic Semiconductor), the electron and hole concentrations are n
1p
1 respectively. By doping impurity atoms the SC becomes extrinsic then the electrons and hole concentrations n
2p
2 respectively, then the following equations are acceptable
n1p1 = n2p2 = ni2For Intrinsic Semiconductor, n = p = ni2 and as per questions before doping n1p1 = ni2
Therefore,
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A semiconductor sample at room temperature has intrinsic concentratio...
To determine the minority carrier concentration after doping a semiconductor sample, we need to understand the concept of doping and its impact on the carrier concentrations.
Doping is the process of intentionally adding impurities to a semiconductor material to alter its electrical properties. The impurities used for doping are typically atoms of different elements, such as Boron (B) or Phosphorous (P), which have either fewer or more valence electrons than the semiconductor material.
Intrinsic concentration (ni) is the carrier concentration in an undoped semiconductor material at a given temperature. It represents the equilibrium concentration of both the majority (holes in p-type material or electrons in n-type material) and minority carriers (electrons in p-type material or holes in n-type material).
Given data:
Intrinsic concentration (ni) = 2.5 x 10^17 /m^3 (equilibrium concentration of both majority and minority carriers)
Majority carrier concentration = 5.5 x 10^21 /m^3 (after doping)
To find the minority carrier concentration, we can use the equation:
np = ni^2 / n
Where np is the minority carrier concentration, ni is the intrinsic concentration, and n is the majority carrier concentration.
Calculation:
Substituting the given values into the equation:
np = (2.5 x 10^17 /m^3)^2 / (5.5 x 10^21 /m^3)
np = 6.25 x 10^34 /m^6 / 5.5 x 10^21 /m^3
np = 1.136 x 10^13 /m^3
Therefore, the minority carrier concentration after doping is 1.136 x 10^13 /m^3.
Hence, the correct answer is option 'A': 1.136 x 10^13 /m^3.