A sample of Ge is doped with acceptors to a level N_a = 4 x 10^14 cm^-3 and donors to a level N_d = 1.6 x 10^14 cm^-3. Assume that the impurities are fully ionized at room temperature.
a) Is the sample n-type or p-type? why?
b) What is the concentration of electrons in the sample? holes?
c) What is the position of the Fermi energy?