Fabrication and properties of B–N codoped p-type ZnO thin films

Abstract

A p-type B–N codoped ZnO film was grown on quartz by magnetron sputtering and post-annealing techniques. It has room-temperature resistivity of 2.3 Ω cm, Hall mobility of 11 cm2 V−1 s−1 and carrier concentration of 1.2 × 1017 cm−3, better than the electrical properties of the N-doped p-type ZnO. The ZnO homojunction fabricated by deposition of an undoped n-type ZnO layer on the B–N codoped p-type ZnO layer showed clear p–n diode characteristics. Differing from the N-doped ZnO, the low-temperature photoluminescence spectrum of the codoped ZnO film consists of two dominant peaks located at 3.096 eV and 3.251 eV, respectively. The former is due to radiative electron transition from the conduction band to the Zn vacancy acceptor level, and the latter due to recombination of the donor–acceptor pair. The mechanism of p-type conductivity was discussed in this work.