Fundamental experiments and first-principles theory on high performance ferroelectric hafnia for electronic applications
Abstract
Since their discovery 100 years ago, ferroelectricsmaterials with a switchablespontaneous electrical polarizationhave become part of a vast portfolio of applicationsincluding piezoelectric actuators, high-voltage capacitors, non-linear optical elements andinfrared cameras. Within the microelectronics sector, ferroelectrics have beensuccessfully exploited in non-volatile ferroelectric random access memories. However,success with other devices, such as ferroelectric field effect transistors has been limited.One of the main challenges is the integration of the best-performing perovskiteferroelectrics into CMOS due to the chemical incompatibility between perovskite oxidesand silicon. Another significant challenge is the so-called ferroelectric size effectthedeterioration of ferroelectric properties upon reduction of the film thickness due todepolarizing effects (i.e. the instability of the spontaneous polarization to its selfgeneratedelectric field), which is particularly problematic for ferroelectric field effecttransistors and tunnel junction devices.The recent discovery of ferroelectricity in thin films of doped hafnium oxides hastherefore generated tremendous interest, as hafnia is both highly compatible with silicon,and exhibits robust ferroelectricity at the nanoscale. Since its first discoveryferroelectricity in hafnia has been confirmed by many groups for many materialcompositions, and some general trends in behavior have been established. However, themechanism for ferroelectricity is still poorly understood, and many fundamentalquestions about the unusual ferroelectric properties of hafnia remain.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 11, 2020
- Source ID
- N629092012059
Entities
People
- Pavlo Zubko
Organizations
- Office of Naval Research
- United States Navy
- University College London