Photoluminescence Study of the MgxZn1-xO/CdSeyTe1-y Interface: The Effect of Oxide Bandgap and Resulting Band Alignment

Mg
x
Zn
1-x
O (MZO) has recently gained popularity as a transparent electron contact in CdTe-based solar cells. The value of the conduction band offset (CBO) and, hence, of the MZO bandgap are often considered essential parameters of this interface, as—in theory—the CBO has a strong impact on both the conduction of electrons and the recombination of holes. However, in this contribution, we report MZO/CdSeTe interfaces where recombination appears to be independent of the CBO. The implications of such results are discussed.