Ferroelectric memory technology for aerospace applications

Celis Semiconductor has designed a radiation-hardened 1.5 megabit nonvolatile ferroelectric memory that operates at 3 volts. This memory provides for good retention, virtually unlimited endurance, fast write times, and can operate over a -55°C to 125°C temperature range. This 1.5 megabit memory incorporates twelve 128-kilobit (16K X 8) Strontium Bismuth Tantalate (SBT) ferroelectric memory chips in a one-inch square by approximately .25-inch high multi-chip module. The 128-kilobit ferroelectric chips use a robust two-transistor, two-capacitor memory cell architecture and have a unique addressing scheme to reduce active power requirements and enhance radiation tolerance. The chips are fabricated using radiation-hardened 0.5 micron CMOS underlying circuitry with SBT ferroelectric upper layer processing. This ferroelectric memory provides ideal characteristics necessary for long range deep space missions