Localization of dielectric breakdown sites in 3D through-silicon via (TSV) interconnects by laser stimulation and chip deprocessing

Monday, November 11, 2019: 3:10 PM
F 150/151 (Oregon Convention Center)
Dr. Kristof J.P. Jacobs , Imec, Leuven, Belgium
Dr. Yunlong Li , Imec, Leuven, Belgium
Prof. Ingrid De Wolf , KU Leuven, Leuven, Belgium
Mr. Stefaan Van Huylenbroeck , Imec, Leuven, Belgium
Dr. Eric Beyne , Imec, Leuven, Belgium

Summary:

We report and demonstrate a new methodology for the localization of dielectric breakdown sites in through-silicon via (TSV) structures. We apply an optical beam induced resistance change (OBIRCH) measurement and mechanical/chemical chip deprocessing to localize nm-sized pinhole breakdown sites in a high aspect ratio 3x50 µm TSV array. Thanks to the wavelength-selective absorption process in silicon, we can extract valuable defect depth localization info from our laser stimulation measurement. After chip deprocessing we inspect and localize the defect site in the dielectric liner using a scanning electron microscope (SEM). We confirm our results and analysis by cross-sectioning a TSV with a focused-ion beam (FIB).