Determining Charge Carrier Concentration from Doping in Si Crystal

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The silicon crystal, doped with 10^15 cm^-3 of antimony and 10^16 cm^-3 of boron, is classified as p-type due to the higher concentration of acceptor boron atoms compared to donor antimony atoms. The majority charge carriers are holes, with a concentration of 10^16 cm^-3, while the minority charge carriers, which are electrons, can be calculated using the equation Npo = ni^2/p0, resulting in a concentration of 10^4 cm^-3. Boron contributes one hole per atom, while antimony contributes one electron per atom, reinforcing the p-type classification. The thermal equilibrium densities of electrons (n0) and holes (p0) are essential for determining these concentrations. This analysis highlights the impact of doping on charge carrier dynamics in silicon crystals.
nhrock3
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a silicon crystal is doped with 10^15 cm^-3 atoms of antimony
and its also doped with 10^16 cm^-3 atoms of boron

will the crystal be type p or type n

what will be the concentration of minory charge carriers and majority charge carriers
?

Boron has 3 electrons in outer circle
and Sb has 5 on the outer circle
so its type "p" because there there is more +3 then +5
thats as far as could go
how to find the concentration of minory charge carriers and majority charge carriers
 
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nhrock3 said:
a silicon crystal is doped with 10^15 cm^-3 atoms of antimony
and its also doped with 10^16 cm^-3 atoms of boron

will the crystal be type p or type n

what will be the concentration of minory charge carriers and majority charge carriers
?

Boron has 3 electrons in outer circle
and Sb has 5 on the outer circle
so its type "p" because there there is more +3 then +5
thats as far as could go
how to find the concentration of minory charge carriers and majority charge carriers

But the two doping densities are not the same...
 
boron is an acceptor donates 1 hole per atom.
Sb is a donor, donates 1 electon per atom

10^16 boron atoms vs 10^15 Sb means that this is a P type.

n0p0=ni^2

minority negative charge carriers : Npo=ni^2/p0 = 10^20/10^16 = 10^4 cm^-3

major charge carriers = 10^16
 
what are n0 p0 and ni
?

what N represents in Npo=ni^2/p0 ?
 
n0 is thermal equibrium density of electrons
p0 is thermal equilibruim density of holes

ni = electron density in intrinsic semiconductor

Npo is the thermal equilibrium minority carrier density.
 
how you get that the "major charge carriers = 10^16 "
?
 
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