Novel Self-Aligned Nitride One Time Programming with 2-bit/Cell Based on Pure 90-nm Complementary Metal–Oxide–Semiconductor Logic Technology

Abstract

A novel 2-bit/cell one time programming (OTP) cell with a nitride-based storage node was developed for programmable logic applications. The fully-logic-compatible cell was successfully demonstrated using 90-nm complementary metal–oxide–semiconductor (CMOS) technology with a cell size of 0.358 µm2. This cell adopting source-side injection (SSI) programming scheme has a very large on/off window and superior writing efficiency. The self-aligned nitride storage node exhibits excellent data retention even at a logic gate oxide thickness of less than 2 nm. This new cell supports a promising solution for logic non-volatile memory (NVM) beyond the 90-nm node.