A silicon crystal is doped with phosphorus atoms. (the binding energy of a h atom is 13.6 ev , the dielectric constant of silicon is 12 and the effective mass o

A silicon crystal is doped with phosphorus atoms. (The binding energy of a H atom is 13.6 eV , the dielectric constant of silicon is 12 and the effective mass of electrons in p51. the crystal is 0.4m, ). The gap between the donor energy level and the bottom of the conduction band is nearest to (a) 0.01 eV (b)0.08 eVV (c) 0.02 eV (d) 0.04 eV