The Type Ia supernova (SN Ia) 2013dy in NGC 7250 (d ≈ 13.7 Mpc) was discovered by the Lick Observatory Supernova Search. Combined with a prediscovery detection by the Italian Supernova Search Project, we are able to constrain the first-light time of SN 2013dy to be only 0.10 ± 0.05 days (2.4 ± 1.2 hr) before the first detection. This makes SN 2013dy the earliest known detection of an SN Ia. We infer an upper limit on the radius of the progenitor star of R 0 0.25 R , consistent with that of a white dwarf. The light curve exhibits a broken power law with exponents of 0.88 and then 1.80. A spectrum taken 1.63 days after first light reveals a C ii absorption line comparable in strength to Si ii. This is the strongest C ii feature ever detected in a normal SN Ia, suggesting that the progenitor star had significant unburned material. The C ii line in SN 2013dy weakens rapidly and is undetected in a spectrum 7 days later, indicating that C ii is detectable for only a very short time in some SNe Ia. SN 2013dy reached a B-band maximum of M B = −18.72 ± 0.03 mag ∼17.7 days after first light.

For the system on panel applications, we fabricated and analyzed the polycrystalline silicon (poly-Si) silicon-oxide-nitride-oxide-silicon (SONOS) memory device on different buffer layer such as oxide or nitride. The threshold voltage (VT) and transconductance (gm) are extracted from each device and the X-Ray Diffraction (XRD) measurement is carried out to interpret these characteristics. The results show the device on oxide layer has higher mobility and lower VT than on nitride layer. From the XRD spectra, it can be explained by the fact that the grain size of poly-Si on oxide layer has larger than on nitride layer. The both devices show program/erase characteristics as the potential of SOP memory devices.

This paper discusses the 3-level charge pumping method in planar-type Silicon-Oxide-High-k-Oxid e-Silicon (SOHOS) and Silicon-Oxide-Nitride-Oxide-Silicon (SONOS) devices to find out the reason for degradation of data retention properties. In the CP thechnique, a pulse is applied to the gate of the MOSFET which alternately fills the traps withe electrons and holes, thereby causing a recombination current Icp to flow in the substrate. A 3-level charge pumping method may be used to determine not only interface trap densities but also capture cross sections as a function of trap energy. By applying this method, SOHOS device found to have a higher interface trap density than SONOS device. Therefore, degradation of data retention characteristics is attributed to the many interface trap sites.

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In this paper, the electrical and physical analysis is carried out to investigate the effect of Al2O3 capping layer on ZnO film using atomic layer deposition. ZnO TFTs shows the metallic conduction behavior as Al2O3 capping layer thickness increases. From SIMS analysis, it is found out that the diffusion of Al into ZnO film is enhanced according to Al2O3 capping layer thickness. Moreover, the defects related to oxygen such as oxygen vacancy increase from XPS analysis and ZnO films reveal less compressive stress by substitution of Zn with Al form XRD analysis. That is, the metallic conduction behavior of ZnO TFTs with Al2O3 capping layer can be explained due to increase in the carrier concentration in ZnO channel layer from oxygen vacancy and substitution of Zn with Al.