An intrinsic semiconductor, also called an undoped semiconductor or i-type semiconductor, is a pure semiconductor without any significant dopant species present. The number of charge carriers is therefore determined by the properties of the material itself instead of the amount of impurities. In intrinsic semiconductors the number of excited electrons and the number of holes are equal: n = p. the key concept is "n = p". If the semiconductor is doped by both donor and acceptor equally, then "n = p "still holds, then it is still intrinsic. however, it is not "undoped semiconductor".