PROPERTIES OF THE INTERFACIAL LAYER IN THE HIGH-K GATE STACK AND TRANSISTOR PERFORMANCE

摘要

Effect of the ALD Hft>2 film on the structural and electrical properties of the underlying interfacial SiC>2 layer is discussed. It is shown that the k value of the interfacial layer is increased, which may be caused by the removal of oxygen atom from the oxide region near its interface with the Si substrate. The data indicates that the low temperature chemical oxide may be less stable than thermal oxide with respect to oxygen removal. Chemical oxide interfacial layer exhibits higher density of the fixed charge compared with thermal oxide that correlates to lower mobility observed in the gate stack with the chemical oxide interface.