A dopingless PNIPN 1T-DRAM with high sensing margin and retention time

Abstract Based on the dopingless TFET with a PNIN structure and the undoped P-type SiGe memory cell, we develop an innovative PNIPN 1T-DRAM to simplify the device fabrication process and improve the storage performance. N + -pocket can reduce the lateral tunneling distance at the source/channel tunneling junction, enhancing the electron tunneling rate here and improving PNIPN 1T-DRAM’s sensing margin (SM). SiGe memory cell helps to expand the effective tunneling energy range between the source and the N + -pocket, prolonging the retention time (RT) and further enhancing the SM. By modifying the metal electrode gap, work function, and length, adjusting the memory window’s germanium composition, and accounting for temperature effects, PNIPN 1T-DRAM can achieve an RT of 1.6 s, read current ratio of 4.01 × 10 4 , SM of 2.87 × 10 −6 A μm −1 at room temperature. In comparison to traditional 1T-DRAMs, it can balance memory performance and chip integration, greatly promoting the application potential of TFET-based 1T-DRAMs.