The intrinsic carrier density at 300 K is 1-5 - 1010 -cm3- In silicon for n-type silicon is doped to 2-25 - 1015 atoms -cm3- the equilibrium electron and hole densities are

nbsp;Ans : (c) n = 2.25 × 10^15, p = 1.0 × 10^5 /cm^3 For n type semiconductor Electron density = n= N_D =2.25 × 10^15 atoms /cm^3 Given that, Intrinsic nb ...

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Mass Action Law and Charge Neutrality Principle

The intrinsic...

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The intrinsic carrier density at $300 K$ is $1.5 \times 10^{10} / c m^{3}$ . In silicon for n-type silicon is doped to $2.25 \times 10^{15} a t o m s / c m^{3}$ , the equilibrium electron and hole densities are

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Solution

Ans : (c)
$n = 2.25 \times 10^{15}, p = 1.0 \times 10^{5} / c m^{3}$
For n-type semiconductor
Electron density $= n = N_{D}$
$= 2.25 \times 10^{15} a t o m s / c m^{3}$
Given that,
Intrinsic carrier concentration $= n_{i}$
$= 1.5 \times 10 / c m^{3}$
$∵ n >> n_{i}$
By Mass Action Law :
$n . p = n_{i}^{2}$
$p = \frac{n_{i}^{2}}{n} = \frac{(1.5 \times 10^{10})^{2}}{2.25 \times 10^{15}}$
= $10^{5} a t o m s / c m^{3}$

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The intrinsic carrier density at 300 K is 1.5×1010/cm3. In silicon for n-type silicon is doped to 2.25×1015 atoms/cm3, the equilibrium electron and hole densities are

Ans : (c) n=2.25×1015,p=1.0×105/cm3 For n-type semiconductor Electron density =n=ND =2.25×1015 atoms/cm3 Given that, Intrinsic carrier concentration =ni =1.5×10/cm3 ∵n>>ni By Mass Action Law : n.p=n2i p=n2in=(1.5×1010)22.25×1015 = 105atoms/cm3

The intrinsic carrier density at $300 K$ is $1.5 \times 10^{10} / c m^{3}$ . In silicon for n-type silicon is doped to $2.25 \times 10^{15} a t o m s / c m^{3}$ , the equilibrium electron and hole densities are