A Ge specimen is doped with Al. The concentration of acceptor atoms is 10^(21)"atoms/m"^(3). Given that the intrinsic concentration of electronhole pairs is 10^(19)//m^(3), the concentrationof electrons in the specimen is …….

A Ge specimen is doped with Al. The concentration of acceptor atoms is

1.	A Ge specimen is doped with Al. The concentration of acceptor atoms is 10^(21)"atoms/m"^(3). Given that the intrinsic concentration of electronhole pairs is 10^(19)//m^(3), the concentrationof electrons in the specimen is …….
Answer» `10^(17)//m^(3)` `10^(15)//m^(3)` `10^(4)//m^(3)` `10^(2)//m^(3)` Solution :`10^(17)//m^(3)` For p-type semiconductor `n_(h)~~ N_(A)` where `N_(A)` is the concentration of acceptor atoms. Also `n_(h)n_(e )=n_(i)^(2)` where `n_(h)=` concentration of holes `=10^(21) "atom/m"^(3)` `n_(i)=` CONCENTRATIONOF electron-pair `=10^(19)"atom/m"^(3)` `n_(e )=` concentration of electron, `THEREFORE n_(e )=(n_(i)^(2))/(n_(h))=((10^(19))^(2))/(10^(21))=10^(17)"atoms/m"^(3)`

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A Ge specimen is doped with Al. The concentration of acceptor atoms is 10^(21)"atoms/m"^(3). Given that the intrinsic concentration of electronhole pairs is 10^(19)//m^(3), the concentrationof electrons in the specimen is …….

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