ThephysicalandelectricalpropertiesofBF2+implantedpolysiliconfilmssubjectedtorapidthermalannealing(RTA)arepresented.ItisfoundthattheoutdiffusionofFanditssegregationatpolysilicon/siliconoxideinterfaceduringRTAarethemajorcausesofFanomalousmigration.FluorinebubbleswereobservedinBF2+implantedsamplesatdosesof1×1015and5×1015cm-2afterRTA.