Ferroelectric Field Effect Transistors: negative Capacitance for Efficient Switching

Open Access
Author:
Chen, Victoria L
Area of Honors:
Engineering Science
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Suman Datta, Thesis Supervisor
  • Gary L Gray, Honors Advisor
Keywords:
  • ferroelectric
  • field effect transistors
  • negative capacitance
  • Landau-Devonshire theory
Abstract:
In recent years, there has been an increasing number of issues associated with the continued Metal Oxide Semiconductor Field Effect Transistor (MOSFET) scaling. As feature lengths shrink down to atomic sizes, problems with power consumption, heat dissipation, and quantum effects become more prevalent. The unique properties of ferroelectric materials and their ability to display a negative differential capacitance make them a promising candidate for the use in future transistor technology, and a potential successor to traditional silicon CMOS devices. By placing a ferroelectric material layer in place of the dielectric layer of a MOSFET, it is possible to achieve a subthreshold slope lower than the typical 60 mV/dec limit. This device is called a ferroelectric field effect transistor (FerroFET). In this work, we develop a computational model based on the Landau-Devonshire theory to extract Landau coefficients from polarization-voltage data of a ferroelectric capacitor and simulate the current-voltage behavior of a FerroFET. We computationally demonstrate the gains of FerroFETs over conventional CMOS devices and explore properties of various ferroelectric materials. These FerroFETs have great potential for use in low power applications and could greatly revolutionize the current semiconductor industry.