Low voltage lead titanate/Si one-transistor ferroelectric memory with good device characteristics

Abstract

We have developed one-transistor ferroelectric memory using lead titanate (PTO) as a gate dielectric directly formed on Si without any buffer layer. The PTO/Si metal-oxide-semiconductor field-effect transistor memory has shown a large threshold voltage shift of 1.6 V at only +/-4 V program/erase voltages. The corresponding good interface was achieved by lowering the anneal temperature to 450 degreesC. Besides the sharp capacitance change of 0.17 muF/V cm(2), it was also evidenced by the high mobility of 169 cm(2)/V s close to high-kappa HfO2. In addition, long retention >1000 s and endurance >10(11) stress cycles in the device suggested good memory characteristics. (C) 2004 American Institute of Physics.