Advanced Characterization of Hafnium-Based Ferroelectric Capacitors to Reveal Interdependencies Among Critical Reliability Phenomena

/ Advanced Characterization of Hafnium-Based Ferroelectric Capacitors to Reveal Interdependencies Among Critical Reliability Phenomena

Advanced Characterization of Hafnium-Based Ferroelectric Capacitors to Reveal Interdependencies Among Critical Reliability Phenomena

Master internship - Leuven | More than two weeks ago

Apply advanced electrical and physical characterization techniques to determine how key reliability phenomena interact in imec’s state‑of‑the‑art ferroelectric capacitors.

Ferroelectricmaterials exhibit a spontaneous polarization that can be reversed by applyingan external electric field and that remains stable even in the absence of sucha field. Fluorite‑type oxides, such as HfO₂ and Hf₀.₅Zr₀.₅O₂ (HZO), form aparticularly interesting class of ferroelectrics due to their compatibilitywith standard CMOS fabrication processes and their scalability to thicknessesbelow 10 nm. These properties have generated significant interest in developingnon‑volatile memory technologies based on hafnium‑oxide ferroelectrics.

Type of internship: Master internship

Duration: 1 academic year

Required educational background: Nanoscience & Nanotechnology, Electrotechnics/Electrical Engineering, Physics

University promotor: Jan Van Houdt (KU Leuven)

Ferroelectricrandom‑access memory (FeRAM) has consequently emerged as a promising candidatefor next‑generation non‑volatile memory, as it stores binary information usingthe stable remanent polarization state of a ferroelectric capacitor (FeCAP).This provides several advantages over conventional volatile dynamic RAM (DRAM),including non‑volatility (no refresh), reduced power consumption, superiorscalability, and near‑DRAM‑level access times. Despite substantial improvementsin FeCAPs—the core memory element in FeRAM—several reliability challengesremain. In particular, wake‑up (the needfor initial cycling to achieve the full memory window), fatigue (the reduction of the memory window during repeatedswitching), and imprint (the increasingdifficulty of switching the polarization state over time) continue to limitdevice performance and long‑term reliability.

Theaim of this project is to investigate the degree to which wake‑up, fatigue, andimprint are inter‑related phenomena in FeCAP devices. This will be achievedprimarily through extensive electrical characterization of imec’sstate‑of‑the‑art planar and 3D‑trench FeCAPs. The primary objective is todetermine how changes induced by one phenomenon (e.g., wake‑up) influencedevice sensitivity to the others (e.g., fatigue and/or imprint), ultimatelycontributing to a deeper understanding of reliability limitations inhafnium‑based ferroelectric technologies.

Project Tasks and Objectives

• Collaborate closely withimec’s ferroelectric memory research team.
• Utilize imec’sexperimental facilities to apply advanced device‑level characterizationtechniques on state‑of‑the‑art FeCAP devices.
• Learn to analyze,interpret, and clearly present research findings to a technical audience.