1.

The number of silicon atoms per m^(3) is5 xx 10^(28). This is doped simultaneously with 5 xx 10^(22) atoms per m^(3) of Arsenic and 5 xx 10^(20) per m^(3) atoms of Indium. Calculate the number of electrons and holes given that n_(i) = 1.5 xx 10^(16) m^(-3). Is the material n-type or p-type?

Answer»

SOLUTION :Arsenic is PENTAVALENT and Indium is trivalent.
`n_(e) = 5 xx 10^(22) - 0.05 xx 10^(22) = 4.95 xx 10^(22)`
but `""n_(i)^(2) = n_(e)n_(h)`
`THEREFORE ""n_(h) = (2.25 xx 10^(22))/(4.95 xx 10^(22)) = 0.454 xx 10^(10)`
`n_(h) = 4.54 xx 10^(9) `PER `m^(3)`
since `n_(e) gt n_(h)`, the material is n type.


Discussion

No Comment Found

Related InterviewSolutions