Papers by Keyword: Template Growth

Abstract: CuTCNQ is a charge transfer complex displaying resistive electrical switching when sandwiched between Cu and Al contacts. Corresponding memory cells switch from a native high resistive OFF state (HRS) to a low resistive ON state (LRS) by applying a negative voltage to the Al with respect to the Cu. Inversion of the signal polarity leads to switching from the LRS to the HRS. Typical CuTCNQ preparation occurs by a chemical reaction of a Cu substrate with TCNQ, involving (partial) corrosion of the metal. In this contribution we present electrodeposition of CuTCNQ on Au and Pt substrates, leading – in contrast to previously published dendritically crystal growth – to relatively smooth, micrometer thick layers. Corresponding large area cross-bar memory arrays (200€m by 200€m, with Al top contacts) exhibited up to several thousand write/erase cycles with an ON/OFF current ratio of 5-10. Furthermore preliminary growth experiments with blanket tungsten bottom contact Metal–Oxide–Semiconductor (CMOS) wafers with 250 nm diameter contact holes showed that electrodeposition is a suitable method for CuTCNQ integration.

Abstract: This paper introduces a process for the growth of oxide nanorod, nanotube, and nanocable arrays that combines sol preparation and template-based electrophoretic deposition. Examples are shown that the sol electrophoretic deposition is an effective method for the formation of polycrystalline and single crystal oxide nanorod arrays, nanotube arrays and conformal coating of thin films of oxides on metal nanorods to produce metal-oxide core-shell nanocable arrays.

Abstract: This article summarizes the work of the author’s lab based on crystallography. The topics are categorized in the following three fields: The first category is crystallographic analysis of materials, the second one is correlations between crystal structure and their properties, and the third one is crystallography for processing such as epitaxy, topotaxy and templates. The examples for these categories are: (1) multilayer ceramic capacitor (MLCC); (2) microwave dielectrics of tungstenbronze-type like solid solutions, and piezoelectric materials langasite (La3Ga5SiO14); (3) thin film growth of GaN or AlN on sapphire for example of epitaxy, hydroxy-apatite grown on diopside for topotaxy, and template growth of microwave dielectrics for template. Crystallography is useful in all studies, but is not almighty. Interdisciplinary study between crystallography and solid state physics is necessary to make clear the mechanism of the properties.