Nickel nanoparticle size and density effects on non-volatile memory performance

In this work, the authors present non-volatile memory devices based on nickel nanoparticles deposited by a novel sputtering process at room temperature and demonstrate and discuss the effect of nanoparticle size and density upon optimum device performance. The devices use a mixed dielectric stack comprised of a silicon dioxide tunneling layer and a hafnium oxide layer formed at low temperature. This allows for fabrication of devices with a relatively small thermal budget and superior performance in terms of memory windows and operating voltages. At voltages as low as 8V, the memory window of the devices is as large as 5V. Charge retention measurements confirm the non-volatility of these devices for up to 10 years, and analysis of the leakage currents sheds light on the mechanisms involved that create these charge retention characteristics. (C) 2013 American Vacuum Society.