The Impact of Channel Semiconductor on the Memory Characteristics of Ferroelectric Field-Effect Transistors

In this work, channel semiconductor is identified and demonstrated to have significant impact on the memory characteristics of ferroelectric field-effect transistors (Fe-FETs). It is understood that, to achieve high electron density at on-state, it requires high hole density at the off-state to realize the charge balance and strong ferroelectric polarization switching in n-type Fe-FETs. Therefore, Fe-FETs with a wider bandgap semiconductor channel have a much smaller memory window than Fe-FETs with a narrower bandgap semiconductor channel due to the insufficient polarization switching. The simple device physics suggests that narrow bandgap semiconductor channel such as Ge is preferred for Fe-FETs with large memory window.