A silicon specimen is made into a `P`-type semiconductor by dopping, on an average, one helium atoms per `5xx10^(7)` silicon atoms. If the number density of atoms in the silicon specimen is `5xx10^(28) at om//m^(3)` then the number of acceptor atoms in silicon per cubic centimeter will be

Options

A. `2.5xx10^(30)" atom/cm"^(3)`
B. `1.0xx10^(15)" atom/cm"^(3)`
C. `1.0xx10^(13)" atom/cm"^(3)`
D. `2.5xx10^(34)" atom/cm"^(3)`

Answer

B

Explanation

Number density of atoms in Si
`=5xx10^(28)("atoms")/(m^(3))=5xx10^(22)("atom")/(cm^(3))`
Since 1 atom of indium is doped in `5xx10^(7)` silicon atoms,
`therefore" Since 1 atom of indium is dopped in "5xx10^(7)` silicon atoms,
`therefore" "` Total number of doped indium atoms
`=(5xx10^(22))/(5xx10^(7))=1xx10^(15)("atoms")/("cm"^(3))`
`therefore" Number of acceptor atoms in silicon "=1xx10^(15)("atoms")/(cm"^(3))`