Interdisciplinary Graduate School of Engineering Sciences, Kyushu University
Abstract
We investigated the electrical properties of TaN/HfO2/Si gate stack structure. It was found that the effective work function (Φeff) strongly depends on the interfacial layer formed near the TaN/HfO2 interface. The analysis by X-ray photoelectron spectroscopy (XPS) indicated that Ta oxide is formed near the TaN/HfO2 interface. The results suggested that the modification of Φeff is attributed to the change in the composition of the interfacial layer. The modifiedΦeff is discussed on the basis of the XPS results
