Chemical stability of CVD source materials for high-Tc superconducting films

• Published in: Journal of materials research Vol. 7; no. 6; pp. 1336 - 1340
• Main Authors: Hashimoto, Takuya, Koinuma, Hideomi, Nakabayashi, Masaaki, Shiraishi, Tadashi, Suemune, Youichi, Yamamoto, Takakazu
• Format: Journal Article
• Language: English
• Published: New York, USA Cambridge University Press 01-06-1992; Materials Research Society
• Subjects: Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Crystal growth; Thick film; Chemical stability; Thermogravimetry; Infrared absorption; Organometallic compound; Differential thermal analysis; Experimental study; NMR spectrum; Chemical vapor deposition; High temperature superconductor; Thin film
• DOI: 10.1557/JMR.1992.1336
• EISSN: 2044-5326
• ISSN: 0884-2914

The stability of chemical vapor deposition (CVD) source materials for high-Tc superconducting films was examined by 1H-NMR (nuclear magnetic resonance), 13C-NMR, IR (infrared) absorption, and TG-DTA (thermogravimetry and differential thermal analysis) measurements. Highly purified Ca(DPM)2 (DPM: dipyvaloylmethane: (CH3)3CCOCHCOC(CH3)3) and Sr(DPM)2, utilizing recrystallization and sublimation, easily decomposed at room temperature and changed their thermal properties when they were handled and stored in air or even in an Ar atmosphere without removing adsorbed species such as water. The stability increased by removing a trace of adsorbed species and storing in an Ar atmosphere at −30 °C. Bi(C6H5)3 and Y(DPM)3 showed higher chemical stability than Ca(DPM)2 and Sr(DPM)2.