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The rapid growth in the smart sensor technology (SST) has enabled easier and more economic construction of the structural health monitoring system (SHM). Nevertheless, there is no distributed damage detection algorithm for efficient usage of the computation power of the SST. Therefore, this study aims at developing a new distributed damage detection algorithm suitable for the smart sensor system for the SHM. The algorithm suggested in this study utilizes the damping ratio of a structure, using the structure's energy dissipation ratio. In other words, each smart sensor installed to the structure analyzes the response signals from the structure into a damping ratio, which in turn is computed into an energy dissipation ratio, using the smart sensor's ability to handle data. Thus, this method detects the damages and locations of the damages in a structure using the changes in the energy dissipation ratio it has calculated. In this study proves the usefulness of the developed energy dissipation ratio by numerical simulation.

Chromeless Phase Lithography (CPL) is discussed as interesting option for the 65nm node and beyond offering high resolution and small Mask Error Enhancement Factor. However, it was shown recently that at high NA CPL masks can exhibit large polarization and also phase effects. A well known phase effect occurring for CPL semi dense lines are through focus Bossung tilts. However, another manifestation of phase effects for dense lines and spaces is a reduced contrast for a symmetrical off-axis illumination due to phase errors between 0 th and 1 st diffraction order. In this paper it is shown that these phase effects can lead to a significant contrast loss for dense features smaller than 60nm half pitch. While also present for trench structures, the contrast reduction is more pronounced for mesa style structures. It is shown that for mesa structures an adjustment of etch depth can not recover an ef fective pi-phase shift. Furthermore, significant polarization effects are observed. As an example, the optimum mesa structure for TE polarization is shifted to small lines. For an experimental validation, a CPL mask containing dense lines and spaces was fabricated. Their imaging performance was characterized with an AIMS 45i offering NA’s greater than 1 and linearly polarized illumination as well as by wafer printing. Gratings with pitches down to 100 nm with varying duty cycles were measured with TE, TM and unpolarized dipole illumination. Very good agreement between measurement and simulation results confirmed the validity of theoretical predictions. Keywords: Pellicle, Hyper NA Lithography, Aberration, Apodization, CD uniformity

The Cr-less Phase Shift Mask (CLPSM) has been considered as one of the most practical resolution enhancement techniques (RET) solution providing low Mask Error Enhancement Factor (MEEF) for low k1 geometries for memory and logic semiconductor devices. There are several papers that show the advantages of the CLPSM compared to the other types of RET. Also the required design changes have been widely studied. Manufacturing of CLPSM requires quartz etching additionally to the COG mask process. Contrary to CLPSM, the required characteristics of the quartz etching process for altPSM are well specified. However, the required quality of the etching process for the CLPSM has not been sufficiently evaluated yet. In this paper, the impact of imperfections of the mask manufacturing process, like the effect of quartz sidewall profile, etch depth deviation and quartz trenching during quartz dry etching on mask imaging performance is investigated. Simulations were performed using Solid-CTM to investigate these effects for both mesa and trench type CLPSM for different pitches. A CLPSM mask was manufactured at AMTC to confirm the validity of the simulation through comparing the contrast deviation on various mesa and trench sizes. AIMS measurements have been performed for this purpose.