I'm wiring a new house and have installed a dedicated 15 amp circuit to the hood fan located over the range in the kitchen. Does this circuit need to be on a afci breaker?
Yes, this needs to be on an AFCI
All 15A and 20A, 120V kitchen outlets (not just receptacles, but lighting and fixed appliances too) have been required to be AFCI protected since the 2014 NEC. (See 210.12(A) for the details -- it covers just about any sort of space you'll find within a dwelling unit proper.)