Design, Modeling and Implementation of Polarization Switching Digital to Analog Converter (PDAC)

University Of Colorado At Colorado Springs, Colorado Springs CO

Investigators

Abstract

Ferroelectric thin films are becoming extremely important in the implementation of non-volatile memories with nearly unlimited endurance and fast read and write times compared to conventional floating gate non-volatile memory technology. These thin films have been successfully integrated onto conventional complementary metal oxide semiconductor technology (CMOS). We are proposing a novel application for ferroelectric thin films in the area data conversion. In digital to analog converters, scaling network plays an extremely important role in the overall performance. The scaling network is usually voltage based using resistor networks or charge based using capacitor networks or a combination of both. This proposal investigates the design, modeling and implementation of polarization based scaling network. The proposed digital to analog converter should have less area, reduced power dissipation, reduced substrate noise and higher speed. The project involves developing a suitable SPICE circuit model for the ferroelectric capacitor switching as well as process and material characteristics condition to obtain a given resolution. The model to be developed will also incorporate temperature and voltage dependence characteristic of circuit elements. Capacitor test patterns will be fabricated with Strontium Bismuth Tantalate (SBT) ferroelectric thin films. The SPICE model parameters will be extracted from ferroelectric capacitor characterization. The analog switches, voltage references and comparators will be attached to the CMOS chip by flip chip technology. The module will be tested to verify the performance of PDAC.