DOPING OF NITROGEN ACCEPTORS INTO ZNSE USING A RADICAL BEAM DURING MBE GROWTH

A new method of doping for ZnSe was attempted by using a neutral radical beam during the MBE growth. The radical beam dominantly consisted of N2 molecular radicals at A3-SIGMA-u+ state. The sticking coefficient of nitrogen was remarkably enhanced; thus this doping method was able to incorporate N into ZnSe by 10(19) cm-3. The existence of shallow N acceptors was confirmed by photoluminescence measurements; recombination of free electrons and acceptor holes (FA) at room temperature and recombination of donor-acceptor pairs at low-temperature were observed. The FA emission was observed only for ZnSe layers with moderate doping level, which shows p-type conduction. The carrier concentration was the order of 10(15) cm-3. The activation of N in ZnSe was less than 1%.