A comparative 1/f noise study of GeOI wafers obtained by the Ge enrichment technique and the Smart Cut technology

This paper presents an experimental investigation of Low-frequency Noise (LFN) measurements on Germanium-On-Insulator (GeOI) PMOS transistors processed on different wafers. The wafers are obtained by Ge enrichment technique and by Smart Cut™ technology. The slow oxide trap densities of back interface are used as a figure of merit to evaluate the process. The Smart Cut™ process is evaluated by studying GeOI pMOSFETs, and the enrichment process by studying Si_1−xGe_x (x = 25% and 35%) pMOSFETs. The buried oxide is used as a back gate for experimental purposes. The extracted values are of the same order of magnitude for both processes and are close to those of state of art buried oxide SiO₂/Si interfaces, demonstrating that both the Smart Cut™ and enrichment techniques produce equally good quality interfaces.