Room-temperature ferromagnetism in Mn-NCo-doped p-ZnO epilayers by metal-organic chemical vapor deposition

Mn-N co-doped Zn epilayers were grown by metal-organic chemical vapor deposition. The Mn-N co-doped epilayers exhibit single phase hexagonal wurtzite structure, indicative of the small lattice damage from co-doping. Secondary ion mass spectroscopy analysis indicates that Mn and N atoms have been in situ incorporated into the ZnO epilayer. Hall measurements exhibit the conduction transition from n-type of the N mono-doped ZnO to p-type of the Mn-N codoped ZnO epilayer. This behavior is attributed to the low formation energy of Mn-N neighboring bonds in the co-doped epilayers. Mn doping leads to the low incorporation of N-H and N-N complexes, which are abundant in the N mono-doped epilayer and always act as compensation centers of holes. Moreover, room temperature ferromagnetism has been observed on the above co-doped epilayer, which is possibly due to the hole mediation on the ferromagnetic ordering of Mn atoms.