Photoluminescence and photoluminescence excitation studies of lateral size effects in Zn_{1-x}Mn_xSe/ZnSe quantum disc samples of different radii

Quantum disc structures (with diameters of 200 nm and 100 nm) were prepared from a Zn_{0.72}Mn_{0.28}Se/ZnSe single quantum well structure by electron beam lithography followed by an etching procedure which combined dry and wet etching techniques. The quantum disc structures and the parent structure were studied by photoluminescence and photoluminescence excitation spectroscopy. For the light-hole excitons in the quantum well region, shifts of the energy positions are observed following fabrication of the discs, confirming that strain relaxation occurs in the pillars. The light-hole exciton lines also sharpen following disc fabrication: this is due to an interplay between strain effects (related to dislocations) and the lateral size of the discs. A further consequence of the small lateral sizes of the discs is that the intensity of the donor-bound exciton emission from the disc is found to decrease with the disc radius. These size-related effects occur before the disc radius is reduced to dimensions necessary for lateral quantum confinement to occur but will remain important when the discs are made small enough to be considered as quantum dots.Comment: LaTeX2e, 13 pages, 6 figures (epsfig

Electrical modalities beyond pacing for the treatment of heart failure

In this review, we report on electrical modalities, which do not fit the definition of pacemaker, but increase cardiac performance either by direct application to the heart (e.g., post-extrasystolic potentiation or non-excitatory stimulation) or indirectly through activation of the nervous system (e.g., vagal or sympathetic activation). The physiological background of the possible mechanisms of these electrical modalities and their potential application to treat heart failure are discussed

Nanoimprint lithography: full wafer replication of nanometer features

International audienceNanoimprint Lithography (NIL) is a fast, high resolution replication technology for micromechanics, microbiology and even for microelectronic applications in the sub-100nm range. The technique has been demonstrated to be a very promising next generation technique for large-area structure replication up to wafer-level in the micrometer and nanometer scale. For producing nanometer structures the capital investments required are much lower compared to other next generation methods (e-beam writing, x-ray lithography, EUV lithography, ...). Nanoimprint Lithography is based on two different techniques: Hot Embossing (HE) and UV-Nanoimprint Lithography (UV-NIL). Both methods can be used for replicating dense and isolated features in the range of 70nm to 100μm simultaneously on up to 200mm wafers

Advanced metrology for the 14 nm node double patterning lithography

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200mm NIL : process improvement using polymer surface modification by plasma treatment

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Characterization of 8 inch wafers printed by Nanoimprint Lithography

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