Possible p -type doping with group-I elements in ZnO

Based on first-principles calculations, we suggest a method for fabricating p-type ZnO with group-I elements such as Li and Na. With group-I dopants alone, substitutional acceptors are mostly self-compensated by interstitial donors. In ZnO codoped with H impurities, the formation of compensating interstitials is severely suppressed, and the acceptor solubility is greatly enhanced by forming H-acceptor complexes. The H atoms can be easily dissociated from these defect complexes at relatively low annealing temperatures, and thus low-resistivity p-type ZnO is achievable with dopants different from group-V elements.