Secondary electron imaging of embedded defects in carbon nanofiber via interconnects

Carbon nanofiber (CNF) via interconnect test structures are fabricated with the bottom-up process proposed by Li et al. [Appl. Phys. Lett. 82, 2491 (2003)] for next-generation integrated circuit technology. Critical defects in the interconnect structure are examined using scanning electron microscopy. It is shown that secondary electron signal with optimized incident beam energy is useful for detecting embedded defects, including unexposed CNF plugs and voids in the dielectric layer. The defect imaging mechanisms are elucidated based on beam-induced charging of the specimen surface

Minority-carrier diffusion length, minority-carrier lifetime, and photoresponsivity of β-FeSi2 layers grown by molecular-beam epitaxy

We have epitaxially grown undoped β-FeSi2 films on Si(111) substrates via atomic-hydrogen-assisted molecular-beam epitaxy. β-FeSi2 films grown without atomic hydrogen exhibited p-type conduction with a hole density of over 1019 cm−3 at room temperature (RT). In contrast, those prepared with atomic hydrogen showed n-type conduction and had a residual electron density that was more than two orders of magnitude lower than the hole density of films grown without atomic hydrogen (of the order of 1016 cm−3 at RT). The minority-carrier diffusion length was estimated to be approximately 16 μm using an electron-beam-induced current technique; this value is twice as large as that for β-FeSi2 prepared without atomic hydrogen. This result could be well explained in terms of the minority-carrier lifetimes measured by a microwave photoconductance decay technique. The 1/e decay time using a 904 nm laser pulse was approximately 17 μs, which is much longer than that for β-FeSi2 prepared without atomic hydrogen (3 μs). The photoresponsivity reached 13 mA/W at 1.31 μm, which is the highest value ever reported for β-FeSi2 films

A Case of Olfactory Neuroblastoma (Esthesioneuroblastoma)Presenting with Anemia Due to Nasal Bleeding

Article信州医学雑誌 64(5): 247-252(2016)journal articl