Characteristics of Memory Window and Retention Properties of One Transistor Memory Devices

Abstract

AbstractPb3Ge5O11(PGO) metal-ferroelectric-metal-oxide-semiconductor (MFMOS) and metalferroelectric-oxide-semiconductor (MFOS) one-transistor ferroelectric memory devices have been fabricated. The memory windows of the memory transistors can be characterized in terms of MFMOS or MFOS capacitor and the threshold voltages of the transistor. The retention properties of one-transistor memory devices can be measured from the changes of the capacitance of MFMOS or MFOS capacitors. Alternatively the retention properties can be evaluated from the threshold voltages or drain currents of the transistor with retention time. There are inconsistencies between the capacitor data and the transistor data. In this paper, we present the memory windows and retention properties of MFOS and MFMOS one-transistor memory devices measured with various methods. The different results obtained from various methods and device structures will be discussed.