Multiple coating of titanium-boron oxide sol-gel on glass

• Published in: Materials research bulletin 1992-06, Vol.27 (6), p.715-722
• Main Authors: Hsieh, Chih-Wen, Chiang, Anthony S.T., Lee, Cheng-Chung, Tu, Shun-Lih
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Physics; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0025-5408; 1873-4227
• DOI: 10.1016/0025-5408(92)90079-F

TiO 2/1b B 2 O 3 composite thin films have been coated on microscope slides by a multiple dip-coating technique. Films produced with heating steps between the deposition of successive layers exhibit a better optical quality than those without. The former have a smaller grain size, less than 30 nm as measured by SEM, and therefore result in less transmittance loss at the short wavelength region. X-ray diffraction studies show that these films are amorphous even after 500° C calcination, while films produced without intermediate heating become slightly crystallized after the same treatment. The thickness of the coated film is proportional to the number of layers applied. A film about 200 nm in thickness can be produced by just four coatings. The refractive index of the film is 2.23 as evaluated from the transmission spectrum.