Recrystallization of ion-beam amorphized BSCC thin films S. Hishita a, * , H. Haneda a , S.S. Kim b , J.H. Moon c a Advanced Materials Laboratory, National Institute for Materials Science, 1-1, Nakimi, Tsukuba, Ibaraki 305-0044, Japan b Department of Materials Science and Metallurgical Engineering, Sunchon National University, 315, Maegok-dong, Chonnam Sunchon 540-742, South Korea c Department of Materials Science and Engineering, Chonnam National University, 300, Yongbong-dong, Puk-gu, Kwangju 500-757, South Korea Abstract TheeffectsofoxygenionirradiationandsubsequentthermalannealingofBi 2 Sr 2 Ca 1 Cu 2 O x (Bi-2212) films deposited onMgO(001)byusingpulsedlaserdepositionwerestudied.Itwasfoundthatcomparedwiththeheated-onlyfilm,the ion irradiated and thermally annealed one showed an improved conducting behavior in the Bi-2212 phase. Our results suggest that amorphization by oxygen ion bombardment and recrystallization by thermal annealing might be a suitable process for the preparation of high-quality superconducting Bi-2212 films. Ó 2003 Elsevier Science B.V. All rights reserved. PACS: 74.72.Hs; 74.78.Bz; 68.55.Jk; 61.80.Jh Keywords: Bi-2212; Superconductor; Thin film; Recrystallization; Ion irradiation; Amorphization 1. Introduction The Bi 2 Sr 2 Ca n1 Cu n O x system is thought to be one of the most promising high-T c superconduct- ing compounds for use in applications ranging from power transmission cables to Josephson- junction-based electronic devices [1–5]. Its thin film form has been successfully prepared using various deposition methods [6–9]. However, to get a high-enough-quality Bi 2 Sr 2 Ca 1 Cu 2 O x (Bi-2212) thin film to be applicable to electronic devices, the growth conditions must be optimized very care- fully. The ion implantation technique is one of the most convenient methods of modifying and/or fabricating a wide variety of materials. The at- tempts to fabricate superconducting films by direct ionimplantation,however,havebeenconsiderably less successful. On the other hand, one of the most successful applications of ion implantation has been its use to improve the critical current (J c ) of high-T c superconductors [10]. In contrast with J c , T c is decreased by ion implantation [11]. Another capability of ion implantation with regard to materials modification is ion-beam- induced crystallization. Since the first report on Si recrystallization with an ion beam [12], this tech- nique has been successfully applied to grow epit- axial films of a variety of materials at low temperature [13–17]. The crystal growth of high-T c materials at low temperature with an ion beam, * Corresponding author. Tel.: +81-298-58-5643; fax: +81- 298-52-7449. E-mail address: hishita.shunichi@nims.go.jp (S. Hishita). 0168-583X/03/$ - see front matter Ó 2003 Elsevier Science B.V. All rights reserved. doi:10.1016/S0168-583X(03)00715-8 Nuclear Instruments and Methods in Physics Research B 206 (2003) 171–174 www.elsevier.com/locate/nimb