Influence of sequential etching on YBCO films deposited by PLD from a nanostructured target

Abstract

Thin YBa 2 Cu 3 O 6+ (YBCO) films with = 90 K and high critical current in the order of 10 7 A cm 2 at 77 K are prepared with pulsed laser deposition from a nanostructured target. Changes in the superconducting and structural properties of the films are investigated after repeated thinning by Ar-ion sputtering or by electrochemical etching. As shown by Auger depth profiling, the chemical composition is preserved through the film during Ar-ion sputtering while electrochemical etching changes the atomic concentrations and surface structures. Investigations by SQUID magnetometry and by conventional resistivity measurements give evidence that the dependence of on the film thickness is similar to as-prepared ultrathin films. The thickness dependence of indicates an excess of pinning centers on the surface of the as-deposited film.

Simulation of Inhomogeneous Superconducting Properties of YBCO HTS Tapes

“…On the other side, the critical current density of YBCO tape is far lower than that of YBCO films. For example, the of small film produced by PLD process could be higher than [4], while the of HTS tape produced by the similar process is about . To date, there is not an effective depiction of the inhomogeneities of superconducting properties, and the investigations on these problems are rarely reported [5].…”

Surface character of laser assisted wet chemical etching of YBCO high temperature superconducting film

“…Following the extensive applications [1] of YBCO High temperature superconducting film and relative devices in the fields of aviation, spaceflight and military, the etching technology of YBCO film become the worldwide researching emphases [2]. Wet chemical etching and dry ion etching are the main etching technologies of YBCO film in existence [3], but these two methods have intrinsic limitations.…”

“…Wet chemical etching and dry ion etching are the main etching technologies of YBCO film in existence [3], but these two methods have intrinsic limitations. The disadvantages of common wet chemical etching technology include low etching rate, long etching duration, marked traverse etching and so on [4]. Whereas for the influence of ion damage on YBCO film underlay [5] and excess etching in dry ion etching technology [6], the capability such as velocity and frequency will be affected badly with the development and application of multilayer YBCO devices [7].…”

“…The typical types are metal-plate monopole antennas with simple configurations [1], CPW-fed UWB antennas that are easier to be integrated with circuits [2], and doublesided printed antennas with a little higher gains [3]. However, it is noticed that the WLAN band from 5.15 to 5.825 GHz is overlapped with the UWB frequency band.…”

“…To avoid the potential interference, some UWB antennas having a frequency band notch function are designed. Fractal configuration [4] and planar monopole antenna with slot [5] are among the common designs. However, the former configuration is too complex while the ground of the latter is a little large.…”