Sketch the energy band diagram and comment on whether a very heavy doping is important, unimportant, or unacceptable for

(a) an ohmic contact between P+ type silicon and TiSi2 at equilibrium,

(b) an ohmic contact between N+type silicon and TiSi2, and

(c) a rectifying contact between Ptype silicon and TiSi2 under 2 V reverse bias.