Determining Charge Carrier Concentration from Doping in Si Crystal

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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 "
?