Probing Surface Conductivity in Ultra-thin ALD ZnO Films
MetadataShow full item record
Previous resistivity measurements of ultra-thin ZnO films reveal a change from semiconductive to metallic behavior at low temperatures for the Zn-terminated surface. The present work confirms this change using IR transmittance spectroscopy measured as a function of temperature. Suggested by the crystal structure of ZnO, the results are consistent with a competition between surface stabilization mechanisms. One of the proposed stabilization mechanisms, a partial charge transfer from the O-terminated surface to the Zn-terminated, would result in metallization of the Zn-terminated surface. This would explain the observed metallic behavior, which appears to be the favor mechanism at lower temperatures.