A 1-kbit EEPROM in SIMOX technology for high-temperature applications up to 250 °C

A 1-Kbit high-temperature EEPROM memory module has been developed in a 1.6-mu m thin-film SIMOX technology. The memory array is based on single-poly EEPROM cells, which are erased and programmed by Fowler-Nordheim tunneling, Operation at elevated temperatures is achieved by a special array design, suitable for elimination of cell-disturb problems caused by temperature-induced leakage currents of the select transistors. High-voltage switching is done without PMOS transistors in order to avoid leakage currents due to the backgate effect. The memory module is designed for 5-V-only operation and offers an access time of 260 ns at an operating temperature of 250 degrees C. At 250 degrees C, data retention of 3000 h and an endurance of 10 000 erase/program cycles has been achieved. The area of the 1-Kbit memory module is 0.89 x 2.71 mm(2).