Interfacial characteristics of Au/Al2O3/InP metal-insulator-semiconductor diodes

• Main Authors: Hogyoung Kim, Yong Kim, Byung Joon Choi
• Format: Article
• Language: English
• Published: AIP Publishing LLC 2018-09-01
• Series: AIP Advances
• Online Access: http://dx.doi.org/10.1063/1.5047538

The interfacial properties of Au/n-InP contacts with a thin layer of Al2O3 (0.7 or 2.7 nm) deposited by atomic layer deposition (ALD) were investigated using temperature-dependent current-voltage (I–V–T) and depth-resolved X-ray photoelectron spectroscopy (XPS) measurements. Schottky barrier inhomogeneity provided a good description of the charge transport at the interface of all the samples. Based on XPS analysis, the removal of native oxide occurred due to a self-cleaning effect via the ALD process, especially for the thicker Al2O3 layer. The significant diffusion of In into the Al2O3 of the thinner layer may have formed In2O3 and degraded the Al2O3 film. XPS analysis also showed that with increasing Al2O3 thickness, emission from In2O3 decreased while that from InPO4 increased.