Suppose a pure Si crystal has 5 xx 10^(28)atoms m^(-3). It is doped by 1 ppm concentration of pentavalent As. Calculate the number of electrons and holes. Given that n_(i) = 1.5 xx 10^(16) m^(-3).

Suppose a pure Si crystal has 5 xx 10^(28)atoms m^(-3). It is doped by

1.	Suppose a pure Si crystal has 5 xx 10^(28)atoms m^(-3). It is doped by 1 ppm concentration of pentavalent As. Calculate the number of electrons and holes. Given that n_(i) = 1.5 xx 10^(16) m^(-3).
Answer» Solution :`n_(c) = 4.95 xx 10^(22), n_(h) = 4.75 xx 10^(9)`, n-type since `n_(e) gt gt n_(h)` For charge NEUTRALITY `N_(D)-N_(A) = n_(e).n_(h) = n_(i)^(2)` Solving these EQUATIONS, `n_(e) = 1/2 [(N_(D)-N_(A)) + sqrt((N_(D)-N_(A))^(2) + 4n_(i)^(2))]`

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Suppose a pure Si crystal has 5 xx 10^(28)atoms m^(-3). It is doped by 1 ppm concentration of pentavalent As. Calculate the number of electrons and holes. Given that n_(i) = 1.5 xx 10^(16) m^(-3).

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