Solid-State Electronics, Vol.48, No.10-11, 2035-2039, 2004
Characterizing damage to ONO dielectrics induced during programming SONOS/NROM (TM) non-volatile semiconductor memory (NVSM) devices
We present experimental results on scaled silicon-oxide-nitride-oxide-silicon (SONOS/NROM(TM)) transistors using a variety of programming mechanisms. These devices store holes and electrons in traps in a nitride layer in the gate dielectric. Programming is achieved with a variety of mechanisms: modified Fowler-Nordheim (MFN) tunneling, channel hot electron injection (HEI), and hot hole injection (HHI). All measurements are performed on transistors with gate dielectrics composed of a tunneling oxide (X-OT), silicon-nitride charge-storage layer (X-N), and a blocking oxide (X-OB) of 4, 4.2, and 4.4 nm (NROM(TM)) or 2, 7, and 4 nm (SONOS), respectively. Charge pumping measurements are employed to characterize the interface trap density of fresh devices and monitor the generation of new interface traps during write/erase operations. We study the damage to ONO dielectrics caused by write/erase cycling by comparing interface trap densities for SONOS/NROM(TM) devices programmed using varying charge-injection mechanisms after 10(6) write/erase cycles for 10 year retention. (C) 2004 Elsevier Ltd. All rights reserved.