The intrinsic carrier concentration of silicon sample at 300 K is 1.5 × 1016 m-3 . What is the density of minority carrier ? (after doping, the number of majority carriers is 5 × 1020 m-3 )

Question

The intrinsic carrier concentration of silicon sample at 300 K is 1.5 × 1016 m-3 . What is the density of minority carrier ? (after doping, the number of majority carriers is 5 × 1020 m-3 ) (A)  4.5 × 1011 m-3  (B)  3.3 × 104 m-3  (C)  5 × 1020 m-3  (D)  3 × 10-5 m-3

Tardigrade Admin · Accepted Answer

ni=1.5×1016 m-3; no=5×1020 m-3 po=(ni2/no)=((1.5×1016m-3)2/5×1020 m-3) =4.5×1011 m-3

Q. The intrinsic carrier concentration of silicon sample at $300 K$ is $1.5 \times 1 0^{16} m^{- 3}$ . What is the density of minority carrier ? (after doping, the number of majority carriers is $5 \times 1 0^{20} m^{- 3}$ )

$4.5 \times 1 0^{11} m^{- 3}$

$3.3 \times 1 0^{4} m^{- 3}$

$5 \times 1 0^{20} m^{- 3}$

$3 \times 1 0^{- 5} m^{- 3}$

$n_{i} = 1.5 \times 1 0^{16} m^{- 3};$
$n_{o} = 5 \times 1 0^{20} m^{- 3}$
$p_{o} = \frac{n _{i}^{2}}{n _{o}} = \frac{( 1.5 \times 1 0 ^{16} m ^{- 3} ) ^{2}}{5 \times 1 0 ^{20} m ^{- 3}}$
$= 4.5 \times 1 0^{11} m^{- 3}$

Q. The intrinsic carrier concentration of silicon sample at 300K is 1.5×1016m−3 . What is the density of minority carrier ? (after doping, the number of majority carriers is 5×1020m−3 )

4.5×1011m−3

3.3×104m−3

5×1020m−3

3×10−5m−3