The Effects of ONO thickness on Memory Characteristics in Nano-scale Charge Trapping Devices

In the use of single/few electrons in distributed storage for nonvolatile, low power and fast memories, providing statistical reproducibility at the nanoscale is a key challenge since relative variance has a radic n dependence and we are working with limited number of storage sites. We have used defects at interfaces of dielectrics to evaluate this reproducibility and evaluate the performance of memories. These experiments show that nearly 100 electrons can be stored at 30 nm dimensions, sufficient for reproducibility, and that a minimum of tunneling oxide thickness is required to assure reliable retention characteristics. Different tunneling oxide thicknesses and the effect of low doped drain (LDD) process is investigated to draw these conclusions.