FERROELECTRIC FIELD-EFFECT TRANSISTORS
Abstract
For more than half a century, tantalizing devices exploiting ferroelectric-semiconductor interfaces have been proposed, but their realization has been thwarted because of materials integration issues. These devices include non-volatile ferroelectric field-effect transistors whose logic states require no power to maintain and can be read out non-destructively based on the conductance of the semiconductor channel. These low-power transistors can beat the 60 mV/decade subthreshold slope limit of conventional transistors. The critical missing link to achieve these ferroelectric transistors is the ability to integrate high-performance ferroelectrics directly with high-performance semiconductors to realize these promising devices relevant to the AFOSR’s C4ISR needs. The PI’s approach is to employ a recently discovered high-performance oxide semiconductor that is structurally and chemically compatible with ferroelectric oxides: BaSnO3. The PI will leverage AFOSR’s 3-year investment in his research on BaSnO3 films and transistors that recently ended. In it he demonstrated MOSFETs based on BaSnO3 channel layers with a more than 20× boost in drain current over all prior BaSnO3-based transistors, producing one of the highest performance transparent transistors ever made. Underlying this achievement is the ability to deposit high mobility BaSnO3 films (the PI has the world record) and pattern them to submicron dimensions (the PI developed an etch that preserves the high mobility and conductivity of the BaSnO3 layer). Although they provide record performance, these devices are limited by the huge density of threading dislocations (?? ~1011 cm–2) that diminish channel mobility. Realizing that with appropriate substrates these devices could perform far better, the PI and his collaborators at the Institute for Crystal Growth in Germany have developed a new substrate that is ideal for this work, Ba2ScNbO6. The present opportunity is to exploit this foundation to produce and assess the performance of the long sought ferroelectric field-effect transistor.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 12, 2021
- Source ID
- FA95502010102
Entities
People
- Darrell G. Schlom
Organizations
- Air Force Office of Scientific Research
- Cornell University
- United States Air Force