Bipolar Junction Transistor, A silicon n-p-n bipolar junction transistor is designed with emitter, base and collector doping levels of 10^19cm, 10^15cm and 5*10^17cm, respectively. Assuming the intrinsic carrier concentration (ni) in silicon to be 10^10cm, calculate the Fermi Energy, Ef, relative to the intrinsic energy scale clearly to show the relative positions of Ef and Efi for each layer.