Improvement of the Sensing Window on a Capacitorless 1T-DRAM of a FinFET-Based Unified RAM

Abstract

A novel initialization concept is demonstrated to improve the program efficiency of the 1T-DRAM mode of unified random access memory (URAM). The proposed method involves boosting the gate-induced drain leakage current for the generation of excess holes by pretrapping electrons to the nitride layer prior to the activation of 1T-DRAM mode. The proposed initialization concept doubles the current sensing window in 1T-DRAM operation. Due to the potential for soft erasing caused by hot-hole injections into electrons that are trapped in the nitride during the P/E cycling of 1T-DRAM, immunity against soft erasing is confirmed through a dc stress measurement as well.