Depth-resolved cathodoluminescence spectroscopy, current-voltage, capacitance-voltage, and deep level transient spectroscopy of ZnO (0001) Zn- and (000) O-polar surfaces and metal interfaces show systematically higher Zn-face near band edge emission and lower near-surface defect emission. Even with remote plasma decreases of the 2.5 eV near-surface defect emission, (0001)-Zn face emission quality still exceeds that of (000)-O face. Ultrahigh vacuum-deposited Au and Pd diodes on as-received and O2/He plasma-cleaned surfaces display a strong polarity dependence that correlates with defect emissions, traps, and interface chemistry. A comprehensive model accounts for the polarity-dependent transport properties and their correlations with carrier concentration profiles.
Look, D. C.,
Song, J. J.,
& Brillson, L. J.
(2008). Zn- and O-Face Polarity Effects at ZnO Surfaces and Metal Interfaces. Applied Physics Letters, 93 (7), 72111.