Suppose a pure crystal has 5xx10^(28) atoms m^(-3). It is doped by 1 part per million concentration of pentavalent As . Calculate the number of electrons and holes . Given that n_(i)=1.5xx10^(16)m^(-3).

Suppose a pure crystal has 5xx10^(28) atoms m^(-3). It is doped by 1 p

1.	Suppose a pure crystal has 5xx10^(28) atoms m^(-3). It is doped by 1 part per million concentration of pentavalent As . Calculate the number of electrons and holes . Given that n_(i)=1.5xx10^(16)m^(-3).
Answer» Solution :Note that 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)`, `n_(e)=(5xx10^(28))/(10^(6))=5xx10^(22)` The number of holes `n_(h)=(2.25xx10^(32))//(5xx10^(22))~4.5xx10^(9)m^(-3)`

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Suppose a pure crystal has 5xx10^(28) atoms m^(-3). It is doped by 1 part per million concentration of pentavalent As . Calculate the number of electrons and holes . Given that n_(i)=1.5xx10^(16)m^(-3).

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