In this study, the phenomenon of light trapping in Si solar cells coated with metal (Au) and dielectric (TiO 2 , SiO 2 ) nanoparticles (NPs) is systematically investigated. In contrast to previous reports, herein it is proposed that the photocurrent enhancement of solar cells should be attributed to the limited antirefl ection ability of the Au NP arrays. In other words, the Au NP arrays might not enhance the absorption of the active layer in cells when no light is refl ected from the air-substrate interface. Therefore, the Au NPs are replaced with dielectric NPs, which possess lower extinction coeffi cients, and then the antirefl ection property of the TiO 2 NP arrays is optimized. A simple, rapid, and cheap solution-based method is used to prepare close-packed TiO 2 NP fi lms on Si solar cells; these devices exhibit a uniform and remarkable increase (ca. 30%) in their photocurrents. To the best of the authors' knowledge, this uniform photocurrent enhancement is greater than those obtained from previously reported metal and dielectric NP-enhanced Si wafer-based solar cells.

High-quality Al 2 O 3 and Si 3 N 4 dielectrics synthesized in a molecular/atomic deposition system were developed and adopted as blocking oxide and tunnel dielectric, respectively in a SONOS-type NAND flash memory cell. In particular, the use of trap-free Si 3 N 4 as tunnel dielectric enables low-voltage erase operation due to its low barrier height for holes, and the relatively high-k value of Al 2 O 3 enhances the low-voltage and high-speed program/erase (P/E) operations. We fabricated and investigated NAND flash memory cells with metal/Al 2 O 3 /SiN/Si 3 N 4 /Si structure. The fabricated cell shows 3.8-V memory window with P/E conditions of +15 V for 100 µs and −10 V for 10 ms. It also shows good endurance up to 10 000 cycles and more than 1.5-V memory window after ten years.Index Terms-Aluminum oxide, charge trap (CT), flash memory, metal/Al 2 O 3 /SiN/Si 3 N 4 /Si (MANNS), silicon nitride, SONOS, TANOS.

The influence of silver oxide additions on the fracture behavior of YBa2Cu3O7−x superconducting ceramic was studied. The KIC value has been found to increase from about 1 MPa√m to as much as 2.4 MPa√m with the blending of 30 wt.% Ag2O with the 1-2-3 powder. All compositions exhibited increasing resistance to fracture with crack extension. The addition of silver to the monolithic sintered structure not only raises the level of the KR curve, consistent with the rise in KIC, but also increases dKR/dΔa, indicative of an improvement in the cumulative toughening efficiency. Microstructural studies implicated crack face bridging by both the 1-2-3 grains, as well as the Ag component, as a major contribution to the observed improvement in toughening. The superconducting properties of these composites were not adversely affected by additions of up to 20% Ag2O.

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