Publication Date:
2015-12-01
Description:
The source of p -type carriers observed in nitrogen-doped Cu 2 O samples [Appl. Phys. Lett. 82 , 1060 (2003)] was identified by using accurate hybrid density functional calculations. Similar to the case of ZnO, we found that N is a deep acceptor when substituting for O in Cu 2 O and cannot be the source of the observed p -type carriers. Detailed investigation of other N-related defects in Cu 2 O reveals that N 2 substitution for Cu, i.e., (N 2 ) Cu , is a shallow acceptor and can give hole carriers in N-doped Cu 2 O samples. (N 2 ) Cu is not only a shallow acceptor but it also has a lower formation energy than N O in some growth conditions. The calculated emission photo luminescence (PL) peak at 1.89 eV associated with (N 2 ) Cu is also in good agreement with the observed N-related PL peak at ∼1.82 eV in N-doped Cu 2 O sample. To aid future identification by Raman spectroscopy techniques, the vibrational frequencies of N 2 on both Cu and O sites were calculated.
Print ISSN:
0003-6951
Electronic ISSN:
1077-3118
Topics:
Physics
