[16a-Z13-1~12] 13.3 Insulator technology

▲ [16a-Z13-5] [Young Scientist Presentation Award Speech] Defect control of Y₂O₃-based SiGe MOS interfaces properties

〇Tsung-En Lee¹, Kasidit Toprasertpong¹, Mitsuru Takenaka¹, Shinichi Takagi¹ (1.Univ. of Tokyo)

Keywords:high-k, SiGe, interface trap density

SiGe MOSFETs have stirred much attention as p-channel devices, because of the high hole mobility and the appropriate bandgap [1]. However, the undesired formation of GeO_x in the interfacial layers (IL) can be regarded as an origin of the MOS interface degradation [1,2]. As a result, it has been reported that D_it can be reduced by a GeO_x -scavenging process, where the choices of atomic layer deposition (ALD) high-k films, metal gate electrodes and annealing temperature are crucial process parameters. In this study, these impacts on D_it are systematically examined. Furthermore, the physical origins of the D_it reduction in Y₂O₃-based SiGe MOS structures are proposed from the viewpoint of Ge-O networks at SiGe interfaces.