Compound semiconductors can be doped to make n-type and
p-type materials, but the scientist has to make sure that the
proper atoms are substituted. For example, if Ge were doped
into GaAs, Ge could substitute for Ga, making an n-type semi-
conductor; but if Ge substituted for As, the material would be
p-type. Suggest a way to dope CdSe to create a p-type material.
