Electroless Ni–B deposition from an emulsified supercritical carbon dioxide bath

• Published in: Thin solid films 2010-10, Vol.518 (24), p.7505-7508
• Main Authors: Wang, Hung-Yu, Chung, Sung-Ting, Chuang, Yan-Chi, Tsai, Wen-Ta
• Format: Article
• Language: English
• Subjects: Borides; Carbon dioxide; Composition and phase identification; Condensed matter: structure, mechanical and thermal properties; Cracks; Defects and impurities in crystals; microstructure; Deposition; Deposition defect; Electroless nickel deposition; Exact sciences and technology; Hardness; Heat treatment; Mechanical and acoustical properties; Microscopic defects (voids, inclusions, etc.); Nickel; Ni–B film; Physical properties of thin films, nonelectronic; Physics; Precipitation; Structure of solids and liquids; crystallography; Supercritical carbon dioxide; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2010.05.034

The electroless deposition of boron-containing Ni (EN-B) film from a supercritical carbon dioxide (sc-CO 2) bath was introduced. The deposition rate in sc-CO 2 bath was one order of magnitude lower than that at ambient pressure without the presence of sc-CO 2. A more uniform chemical composition of the EN-B film could be obtained if it was deposited in the sc-CO 2 bath. X-ray diffraction analyses revealed that the as-deposited film was amorphous in nature, despite of the deposition condition. Deposition defects such as cracks and voids could be avoided if the deposition was conducted in the sc-CO 2 bath. Crystallization and boride precipitation were found after heat treatment at 400 °C for 1 h. The EN-B film deposited from the sc-CO 2 bath had a higher hardness as compared with that of the normal EN-B coating. A substantial increase in hardness was obtained due to boride precipitation.