Search

ZrO nanocrystallites based charge trap memory cells by incorporating a (ZrO)(SiO) film as a charge trapping layer and amorphous AlO as tunneling and blocking layer were prepared and investigated. The precipitation reaction in charge trapping layer forming ZrO nanocrystallites during rapid thermal annealing was investigated by transmission electron microscopy. The density and size of ZrO nanocrystallites are the critical factors for controlling the charge storage characteristics. The ZrO nanocrystallites based memory cells after postannealing at 800 C for 60 s exhibit the best electrical characteristics and a low charge loss ∼5 % after 10 write/erase cycles operation. [ABSTRACT FROM AUTHOR]

Amorphous films Zr0.8Si0.2O2 were deposited on quartz substrates at room temperature, by using pulsed laser deposition technique. After annealing at high temperature, Zr0.8Si0.2O2 films suffer a phase separation to precipitate tetragonal ZrO2 nanocrystals in ZrSiO4 amorphous matrix. Their crystal structure, microstructure, optical absorbance and photoluminescence have been systematically investigated. Tetragonal ZrO2 nanocrystals show intense UV emission around 392 nm under photonic excitation with a wavelength of 250 nm. The corresponding models of electronic excitation and transition related to UV emission also have been proposed. [ABSTRACT FROM AUTHOR]

The structural and optical characterizations of titania incorporated with alumina nanocrystals have been presented in this paper and the films exhibit excellent properties like low current density, small hysteresis as well as high photoluminescence quantum yields of about 361 nm. These properties are promising for the applications in future electronic devices. [ABSTRACT FROM AUTHOR]

A charge trapping memory device using Ti0.2Al0.8Ox film as charge trapping layer and amorphous Al2O3 as the tunneling and blocking layers was fabricated for nonvolatile memory application. TiAl2O5 nanocrystals are precipitated from the phase separation of Ti0.2Al0.8Ox film annealed at 900 °C. A memory window of 2.3 V and a stored electron density of 1×1013/cm2 were obtained. Good retention characteristics of the memory device at 80 °C were observed due to the deep charge trapping level as identified by the valence band offsets and electron energy loss spectrum measurements. [ABSTRACT FROM AUTHOR]

Abstract: Charge trapping memory capacitors using (ZrO2)0.8(SiO2)0.2 film as charge trapping layer and amorphous Al2O3 as the tunneling layer and blocking layer were fabricated for nonvolatile semiconductor memory application. The ZrO2 nanocrystallites with a size of 3–5nm precipitated from amorphous (ZrO2)0.8(SiO2)0.2 during rapid thermal annealing at 800°C can serve as the storage nodes, with which a large hysteresis memory window of 7.5V at a sweeping gate voltage of 8V has been achieved. At 150°C bake temperature, the memory capacitor exhibited an excellent endurance up to 105 write/erase cycles, after which a small charge loss of about 12% was achieved. [Copyright &y& Elsevier]