摘要:

Highly oriented, near‐stoichiometric films of YBa2Cu3O7−&dgr;have been deposited onto (100) MgO, (100) yttria‐stabilized zirconia, and (110) SrTiO3by ion beam sputtering from a single, off‐stoichiometric target. Their crystal structure and resistance behavior were found to depend on the crystallization temperature of a two‐step post‐deposition anneal, which was varied from 750 to 1000 °C. The highest zero‐resistance temperature (73 K) and degree of preferred orientation was observed for a film which was deposited on (100) MgO and annealed for a short time at 950 °C.

ISSN:0003-6951    

DOI:10.1063/1.102430

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

The low‐pressure activated reactive evaporation process was used successfully to grow superconducting thin films that were uniform in thickness, free of cracks, voids, spits, and other source‐related defects, and with mirror‐like surface smoothness. These are important considerations for the practical use of these materials in thin‐film form. No post‐deposition annealing was carried out.Tc(0) for films on yttria‐stabilized zirconia (YSZ) substrates is close to 80 K, and the (001) preferred orientation was observed with higher deposition temperatures in the range 550–650 °C. Films on silicon and sapphire substrates were adversely affected by interdiffusion, showing aTc(0) of 56 and 72 K, respectively.

ISSN:0003-6951    

DOI:10.1063/1.101571

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

The superconducting transport properties of polycrystalline Tl2Ca2Ba2Cu3O10thin films irradiated with 740 keV oxygen ions were monitored as a function of fluence. Both the transition temperature (Tc) and the critical current density (Jc) decreased rapidly with fluence; however, the transition temperature onset remained constant. A fluence of 2×1014O/cm2(0.028 dpa) was sufficient to eliminate superconductivity in the films.Jcat 76 K decreased from 25 000 A/cm2in the unirradiated sample to 2000 A/cm2after a fluence of 2.1×1013O/cm2. A room‐temperature anneal caused bothTcand the normal‐state resistivity to recover slightly after low‐fluence irradiations.

ISSN:0003-6951    

DOI:10.1063/1.102431

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

Periodic and stable micropatterns appeared on the surface of amorphous polyethersulfone etched with an excimer laser at 308 nm in ambient air and a vacuum. The control of such radiative conditions as fluence and incident angle enables us to modify the spacing and pattern of the microstructures. A topographical investigation with scanning electron microscopy and an experiment with x‐ray photoelectron spectroscopy to determine its composition is reported.

ISSN:0003-6951    

DOI:10.1063/1.101863

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

The correct mixing efficiency for the Fe/Al bilayer (900 keV Xe+3, 77K) is presented in the context of the recent analysis by Ma, IE.E., Work man, W.L>, Johnson, W.L., and Nicolet, M.A. (AIP)

ISSN:0003-6951    

DOI:10.1063/1.101864

出版商:AIP    

年代:1989

数据来源: AIP