FETRAM- an Organic Ferroelectric Material Based Novel Random Access Memory Cell

Saptarshi Das, Doctoral Student
Joerg Appenzeller, Birck Nanotechnology Center, Purdue University

Abstract

Ferroelectric Transistor Random Access Memory or FETRAM is an experimentally demonstration of a novel, fully functional, CMOS compatible One-Transistor-One-Transistor (1T1T) memory cell architecture using an organic ferroelectric – PVDF-TrFE – as memory storage unit (gate oxide) and a silicon nanowire as memory read out unit (channel material). FETRAM cell exhibits similarities with state-of-the-art Ferroelectric Random Access Memories (FeRAMs) in that it employs a ferroelectric material to store information in a non-volatile (NV) fashion but with the added advantage of allowing for non-destructive readout. This non-destructive readout is a result of information being stored in our cell using a ferroelectric transistor instead of a capacitor. Use of PVDF-TrFE, a material with low crystallization temperature, allows forming a ferroelectric film on a semiconducting substrate without any chemical reaction, a feat difficult to accomplish with crystalline ferroelectrics. Employing silicon nanowires as channel material for readout operation is motivated by two aspects: Firstly, utilizing silicon in our demonstration as the channel material emphasizes the compatibility with conventional CMOS technology and second, it underlines the potential of our approach for future scaling since nanowires as ultra-thin body channels enable aggressive channel length scaling through improved electrostatic gate control if compared to their bulk or thin film planar device counterparts.