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下部電極としてW薄膜を形成した石英基板上に、プラズマCVDにより柱状Siナノ構造を高密度・一括形成した後、電気化学法による柱状Siの絶縁分離・ナノ結晶化処理後、上部電極として極薄Au電極を形成したAu/柱状Siナノ構造/Wのスタック構造において、導電性AFM探針を用いた二次元電流像の接触および非接触測定を行うことで、柱状ナノ構造の局所電気伝導を評価した。下部W電極-3V、上部Au電極を接地電位として、Au上部電極表面を接触測定した結果、膜中柱状Siナノ構造を反映して、極薄Au電極表面における弾道電子濃度の違いに起因した明瞭な高伝導領域が認められた.さらに、探針-基板間距離200nmで測定した二次元電流像においても、下部電圧-20V以上印加した場合に、非接触にも関わらず直径〜50nmの高伝導領域が明瞭に認められた。この高伝導領域は、表面形状像測定で確認された柱状Siナノ構造と直径が同程度であることから、電極間印加により膜中柱状Siナノ構造からの弾道電子検出で解釈できる。A highly-dense Si nanocolumnar structure accompanied with Si nanocrystals was fabricated on a W layer /quartz by inductively-coupled plasma enhanced CVD and treated with anodic oxidation. And after the formation of a few nanometer thick Au layer as a top-electrode, electron transport properties through Si nanocolumnar structures so-prepared were characterized by means of atomic force microscopy (AFM) with a conductive cantilever in both contact and non-contact modes. When the W bottom electrode was biased at -23V with respect to the grounded Au-top electrode, a current increase of the order of 〜3pA was detected in several areas corresponding to Si nanocolumns even in the condition that the distance between the sample surface and the AFM probe was kept constant typically at 200nm. The result is attributable to the electron emission as a result of inelastic transport through Si nanocrystals via nanocolumnar structure.

We investigated the multireflection effect on the formation of a periodic surface structure produced by a linearly polarized Nd:YAG laser beam of 532 nm on an Si film deposited on a glass substrate, as well as on heating rate in the film, compared with an excimer laser beam. From the theoretical calculation results, it was found that the formation of the periodic surface structure and heating rate strongly depended on film thickness or that they were influenced by the multireflection effect. The thickness most effective for forming the periodic surface structure and heating rate was about 60 nm. Furthermore, we attempted to verify the calculation results by carrying out an experiment in which we checked whether the periodic structure was formed on the surface of the melting-crystallized Si films. As a result, the thickness range for producing the periodic surface structure was found to be from 50 to 70 nm, which were larger than the theoretical values of 40 to 60 nm.

type:Article, We investigated influence of the beam irradiation conditions with oblique incidence on crystallization of an Si film by a linearly polarized pulse laser in order to enlarge the periodic width of grain boundary. The irradiation conditions are fluence, pulse number and film thickness. We can obtain the periodic width of about 900 nm by increasing the incident angle to 25°. The experimental results suggest that the pulse number and the film thickness should be controlled properly as well as fluence in order to produce large grain stably for the oblique incidence. The detail of these conditions was discussed., identifier:https://dspace.jaist.ac.jp/dspace/handle/10119/4009