An ultralow program/erase voltage ( |VP/E| = 4 V) is demonstrated by using an antiferroelectric-ferroelectric field-effect transistor (AFE-FE-FET) through a multipeak coercive E -field ( EC ) concept for a four-level stable state with outstanding endurance (>105 cycles) and data retention (>104 s at 65 °C). The mixture of ferroelectric (FE) and AFE domains can provide stable multistate and data storage with zero bias for multilevel cell (MLC) applications. HfZrO2 (HZO) with AFE-FE assembles an orthorhombic/tetragonal (o/t) phase composition and is achieved by [Zr] modulation in an HZO system. MLC characteristics not only improve high-density nonvolatile memory (NVM) but are also beneficial to neuromorphic device applications.