We investigated the impact of high-pressure annealing (HPA) on the memory properties of one-transistor dynamic random-access memory (1TDRAM) using a coupled geometry of a metal-ferroelectric (Hf0.5Zr0.5O2)-metal (MFM) capacitor connected in series with a gate insulator (SiO2) of a metal-oxide semiconductor field-effect transistor. The MFM capacitors were fabricated under different HPA conditions followed by the measurement of ferroelectric characteristics. The obtained results (polarization-electric field curves) were used for extracting the Landau-Khalatnikov coefficients, and these were used with the help of using Sentaurus TCAD tool, to theoretically study various characteristics of the coupled system (1TDRAM), such as sub-threshold swing (SS), memory window (MW), and ON/OFF current ratio (ION/IOFF). The output reflected that the MFM associated with 550°C HPA provides a wide MW (1.8-2.4 V based on area ratio), and the lowest SS (33mV/decade). Thus, the optimized HPA condition is promising in providing better results for various memory-based applications.