What kind of semiconductor--n-type or p-type--does doping germanium with arsenic create?
COLLECT AND ORGANIZE We are asked to determine the type of semiconductor formed when germanium (Ge,group 14) is doped with arsenic (As, group 15).
ANALYZE The fact that As is in group 15 mean that its atoms have one more valence electron that the atoms of Ge.
SOLVE When the dopant has more valence electrons than the host semimetal, the two form an n-type semiconductor.