Gadolinium oxide nanocrystal ͑Gd 2 O 3 -NC͒ memories treated by postdeposition rapid thermal annealing were investigated. Bandgap offset performed by a crystallized Gd 2 O 3 -NC dot surrounded by amorphous Gd 2 O 3 dielectrics is successfully demonstrated and proven by the transmission electron microscopy images and electron diffraction pattern. The Gd 2 O 3 -NC memory exhibits a hysteresis memory window of 4 V and NC dot density of more than 8.5 ϫ 10 11 cm −2 . In addition, the formation of Gd 2 O 3 -NC and charge loss characteristics on annealing temperature were analyzed and optimized at 850°C. The data endurance of 10 4 program and erase cycling for a sufficient memory window ͑Ͼ2 V͒ was also observed for the Gd 2 O 3 nanocrystal memory.In order to scale down floating gate ͑FG͒ nonvolatile memory ͑NVM͒, tunnel oxide limitation for sufficient charge retention has to be overcome. 1 One way is to implement high-dielectric-constant ͑high-k͒ materials such as Al 2 O 3 thin film as the tunnel oxide for the reduction of operation voltage while satisfying the data retention and endurance. 2 The other is using a discrete charge-storage concept for thinner tunnel oxide without sacrificing nonvolatility. Isolated Si and Ge semiconductor nanocrystal ͑NC͒ memories are NVMs that have been demonstrated to have a more simplified fabrication process, better punchthrough effect, and immunity to oxide defects as compared to conventional FG NVMs. 1,3,4 To achieve the fast write/ erase and long retention time simultaneously, metal NC memories are presented to engineer the depth of the potential well at storage nodes. Heavy metals, 4-7 silicide, 8,9 nitrided-metal, 10 and metal-oxide 11,12 are NC memories used as storage nodes. Compared with the semiconductor NC memories, metal counterparts exhibit a higher density of states around the Fermi level, stronger coupling with the conduction channel, a wider range of available work functions, and smaller energy perturbation due to carrier confinement. 13 Gadolinium oxide ͑Gd 2 O 3 ͒, the rare-earth sesquioxides ͑R 2 O 3 ͒, has been reported to be candidates as gate dielectrics for silicon and compound semiconductor device applications. 14,15 They are demonstrated to exhibit three different structures such as cubic, monoclinic, and hexagonal under different growth temperatures. 16 In addition, a different energy bandgap of amorphous ͑6.3-6.4 eV͒ and crystallized ͑5.0-5.4 eV͒ Gd 2 O 3 thin films has also been discovered. 17,18 Recently, magnetic nanocrystalline Gd 2 O 3 particles embedded in silica glass have been proposed for memory applications. 19 In this work, we demonstrate that a crystallized gadolinium oxide with low bandgap acts as a charge-storage node when it is surrounded by amorphous gadolinium oxide with higher bandgap to form Gd 2 O 3 nanocrystal memories ͑Gd 2 O 3 -NC͒. This separate charge-storage structure is different from the previous research regarding NC memory devices, 4-12 and the tunnel oxide thickness is effectively increased for better charge retention. The memory...

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It has been reported that minute Co additions to Sn-based solders are very effective for reducing undercooling, probably due to low Co solubility in Sn. In this study, Co solubility in molten Sn was determined experimentally. According to results of metallographic analysis, Co solubility in molten Sn is as low as 0.04 wt.% at 250°C. Interfacial reactions in Sn-Co/Ni couples at 250°C were examined for Co contents from 0.01 wt.% to 0.4 wt.%. The Ni 3 Sn 4 phase was the only interfacial reaction phase in almost the entire Sn-0.01 wt.%Co/Ni couple. For Sn-Co/Ni couples with a Co content higher than 0.01 wt.%, a thin, continuous Ni 3 Sn 4 layer and a discontinuous decahedron (Ni,Co)Sn 4 phase were formed in the initial stage of reaction. The reaction products evolved with time. With longer reaction time, the Sn content in the decahedron (Ni,Co)Sn 4 phase decreased, and the (Ni,Co)Sn 4 phase transformed into the (Ni,Co)Sn 2 phase and cleaved into a sheet, which then detached from the interface, after which Ni 3 Sn 4 began to grow significantly with longer reaction times.

Blue sprat (Spratelloides gracilis) is an economically valuable species that inhabits the central Taiwan Strait. However, despite the implementation of a local management scheme involving a closed season between 1 May and 1 June, the annual catch has rapidly decreased over the decades. Thus, the efficacy of the implemented regulations must be investigated. This study sought to clarify the reproductive biology, spawning ground, and behavior of this species in the waters of Penghu. In total, 6,549 specimens were collected between March 2021 and September 2022. Considering gonadosomatic index, group maturity, and oocyte diameter, we found that the spawning season (March–September) peaked in April; new cohorts were distinctly recruited after the spawning peak. The distribution of the spawning ground (latitude, 23°41′N to 23°43′N; longitude, 119°32′E to 119°39′E) was determined by considering the fishing area of mature females and DNA analysis of adhered eggs. We further noted shoals of fish darting in the bottom water without clear schooling movement, females’ abdomen frequently contacting substrata for eggs able to attach on during oviposition, and males releasing sperms making water milky white; these indicate that S. gracilis exhibits promiscuous spawning behavior. Our findings may facilitate the management and conservation of S. gracilis in this region.