Dielectric breakdown behavior of ferroelectric HfO₂ capacitors by constant voltage stress studied by in situ laser-based photoemission electron microscopy

Abstract

The in-situ laser-based photoemission electron microscopy (laser-PEEM) observation with time dependent dielectric breakdown (TDDB) measurements of TiN/Hf0.5Zr0.5O2(HZO)/TiN ferroelectric capacitors were performed to reveal the dielectric breakdown (DB) mechanism. We succeeded in visualizing the hard DB spots through the top electrode. We found that capacitors with short- and long-lifetime distribution were broken down near and far from the edge of the capacitors, respectively. This indicates that DB is either topography-dependent or film quality-dependent. This work demonstrates the effective method of detecting DB in a non-destructive manner to provide an insight for achieving higher endurance of HfO2-based ferroelectric capacitors.