Modeling and simulation of low power ferroelectric non-volatile memory tunnel field effect transistors using silicon-doped hafnium oxide as gate dielectric

Keywords: HfO 2 Analytical model Surface potential Ferroelectric Nonvolatile memory Fe-TFET a b s t r a c t The implementation and operation of the nonvolatile ferroelectric memory (NVM) tunnel field effect transistors with silicon-doped HfO 2 is proposed and theoretically examined for the first time, showing that ferroelectric nonvolatile tunnel field effect transistor (Fe-TFET) can operate as ultra-low power non-volatile memory even in aggressively scaled dimensions. A Fe-TFET analytical model is derived by combining the pseudo 2-D Poisson equation and Maxwell's equation. The model describes the Fe-TFET behavior when a time-dependent voltage is applied to the device with hysteretic output characteristic due to the ferroelectric's dipole switching. The theoretical results provide unique insights into how device geometry and ferroelectric properties affect the Fe-TFET transfer characteristic. The recently explored fer-roelectric, silicon-doped HfO 2 is employed as the gate ferroelectric. With the ability to engineer ferroelec-tricity in HfO 2 thin films, a high-K dielectric well established in memory devices, the silicon-doped HfO 2 opens a new route for improved manufacturability and scalability of future 1-T ferroelectric memories. In the current research, a Si:HfO 2 based Fe-TFET with large memory window and low power dissipation is designed and simulated. Utilizing our presented model, the device characteristics of a Fe-TFET that takes full benefits from Si:HfO 2 is compared with the same devices using well-known perovskite ferroelectrics. Finally, the Fe-TFET is compared with a conventional ferroelectric memory transistor highlighting the advantages of using tunneling memory devices. Ferroelectric materials can be utilized as electrically switchable nonvolatile data storage elements as their polarization can change by applying an external electric field. Recently, novel devices called ferroelectric TFETs [1], and ferroelectric FETs have been proposed as promising candidates for future nonvolatile memory applications [2,3]. In ferroelectric field effect devices, two stable states of the fer-roelectric's polarization are used for data storage [4]. Nonvolatile data storage, fast writing, and nondestructive read-out operation have been reported for ferroelectric field effect transistors [5]. However , the industrial implementation of ferroelectric devices especially in nanoscale still missing due to the integration and scaling obstacles of conventionally used perovskite type ferroelectrics such as Lead Zirconate Titanate (PZT). The recently discovered ferroelectricity in HfO 2 thin films [6], enabled CMOS-compatible manufacturing of highly scaled ferroelectric devices down to 28 nm ground rule [6,7]. By scaling devices down to the nanoscale, power density becomes a challenging issue as the power density per area …