Performance evaluation of ferroelectric MOSFETs based on Gibbs free energy

A comprehensive simulation scheme based on Gibbs free energy calculation is developed to accurately evaluate the device performance of ferroelectric MOSFETs. Its operation region is captured based on the minimum energy point of the whole system involving FE, oxide layer, as well as atomic charge calculation in semiconductor materials. The MOS structure can achieve hysteresis-free mode with negative capacitance effect with both forward and reverse scans. However, for MOSFET structure, the operation region can be affected by different gate lengths of devices and ferroelectric materials. In the selected device, negative capacitance mode can appear with forward scan meanwhile the normal hysteresis effect can appear with reverse scan. This shows hysteresis I-V characteristics and non-symmetric operation loop.