Kageyoshi Sakamoto

Polishing of YBa2Cu3O7−y by He‐ion etching

Clean polishing is performed by helium‐ion etching on a surface of high‐Tc YBa2Cu3O7−y. Based on a knock‐on cascade model, the decrease of surface roughness is discussed. A rate process of etching is applied for the surface roughness of the high‐Tc YBa2Cu3O7−y.

Influence of Ar ion etching on Tc of liquid-quenched Bi1.6Pb0.4Sr2Ca2Cu3Ox superconductor by sheet plasma source

The influence of argon-ion etching is investigated for liquid-quenched high-Tc Bi1.6Pb0.4Sr2Ca2Cu3Ox. The argon-ion irradiation has no effect on the Tc value for a dose of 4.05 × 1017 (ions mm−2). However, doses in excess of this level greatly decreases the Tc value. Therefore, a critical irradiation does value (Dc) to maintain a Tc value above 100 K is defined and determined. The Dc is about 4.94 × 1017 (ions mm−2) for argon-ion irradiation at the low acceleration energy of 1 keV.

Critical etching time to maintain high T c of Bi-oxide

An influence of the argon-ion etching on Tc is investigated for high-Tc Bi1.6Pb0.4Sr2Ca2Cu3Ox. The etching doesn’t decrease the Tc for 7.0 ks. However, excess etching greatly decreases the Tc. Thus, a critical etching time (te C) to maintain high Tc above 100 K is defined and determined. The te C is 8.5 ks for the argon-ion etching.

AGING INDUCED HIGH T C OF EXCESS ETCHED Bi-Pb-Sr-Ca-Cu-O BY He ION

Ion etching is able to form fragile materials without fracture under clean atmosphere. However, the excess etching decreases the T C value tremendously. Thus, we have started the present study to recover the T C mid value of excess etched Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O x . Aging at room temperature recovers the T C value.

POLISHING OF Bi-Pb-Sr-Ca-Cu-O BY He ION ETCHING

Clean polishing is found. It is performed by helium-ion etching on a surface of high-T C Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O x . Based on a knock-on cascade model, the decrease of surface roughness is discussed.

RAPID RATE OF He ION ETCHING RATE OF HIGH T C Bi-Pb-Sr-Ca-Cu-O

A high helium-ion etching rate is observed for the high T C Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O x . The high etching rate (R s ) is found at high angles of incidence (θ) of the ion-beam and at short etching times.

Rapid Rate of He Ion Etching for the High Tc YBa2Cu3O7-y

A rapid rate (Rs) is observed by a helium ion etching. Rs depends on the etching time. Tc change by the etching is studied for a high Tc YBa2Cu3O7-y. A tremendous Tc decrease is caused by a excess helium ion etching.