In situ real-time monitoring of profile evolution during plasma etching of mesoporous low-dielectric-constant SiO 2Patterning of fluorine-, hydrogen-, and carbon-containing SiO 2 -like low dielectric constant materials in highdensity fluorocarbon plasmas: Comparison with SiO 2 O 2 plasma ashing is commonly used to remove photoresist. The effect of O 2 plasma ashing on the porous organosilicate glass (CH 3 SiO 1.5 ) n , one of the spin-on materials, is investigated. O 2 plasma can oxidize the methyl groups in porous organosilicate glass ͑POSG͒, which leads to the formation of Si-OH groups. The hydrophilic Si-OH groups will induce moisture uptake so that electrical degradation will occur in POSG film. Pure hexamethyldisilazane ͑HMDS͒ vapor ͑100% HMDS͒ can react with the Si-OH groups in POSG film. It converts hydrophilic Si-OH groups into hydrophobic Si-O-Si(CH 3 ) 3 groups against moisture uptake. The leakage current density decreases by a factor of 2-3 and the dielectric constant decreases from 3.62 to 2.4 when O 2 plasma-damaged POSG undergoes HMDS treatment at 80°C for 15 min. Therefore, HMDS treatment is the effective technique to repair the electrical degradation to POSG film during photoresist stripping processing.

Spherical and well-separated tungsten nanocrystals embedded in the SiO 2 layer are demonstrated for the low-voltage nonvolatile memory device. The tungsten dots are formed, based on the thermal oxidation of the tungsten silicide, with a mean size and aerial density of 4.5 nm and 3.7 ϫ 10 11 /cm 2 , respectively. A pronounced capacitance-voltage hysteresis is observed with a memory window of 0.95 V under the 3 V programming voltage. Also, the endurance of the memory device is not degraded up to 10 6 write/erase cycles.

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In this study, a distributed charge storage with GeO2 nanodots is demonstrated. The mean size and aerial density of the nanodots embedded in SiO2 are estimated to be about 5.5 nm and 4.3×1011 cm−2, respectively. The composition of the dots is also confirmed to be GeO2 by x-ray absorption near-edge structure analyses. A significant memory effect is observed through the electrical measurements. Under the low voltage operation of 5 V, the memory window is estimated to ∼0.45 V. Also, a physical model is proposed to demonstrate the charge storage effect through the interfacial traps of GeO2 nanodots.