Suppose a pure Si crystal has 5 xx 10^(22) 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^(22) atoms m^(-3) . It is doped

1.	Suppose a pure Si crystal has 5 xx 10^(22) 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 : The thermally GENERATED electrons (`n_(i) ~ 10^(16) m^(-3)`) are negligibly small as compared to those produced by doping . Therefore , `n_(e) ~~ N_(D) ` . Since `n_(e) n_(h) = n_(i)^(2)` , the NUMBER of holes`n_(h)= (2.25 xx 10^(32))// (5 xx 10^(22))` ` ~ 4.5 xx 10^(9) m^(-3)`

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Suppose a pure Si crystal has 5 xx 10^(22) 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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