Vapor Deposited Titanium Dioxide Thin Films: Some Properties as a Function of Crystalline Phase.
Abstract
Thin films of TiO2 are grown in a low temperature (150C) vapor deposition process by hydrolyzing tetraisopropyl titanate at the substrate. These films can be made uniform over a 1-1/4 in substrate to within 100 A and are found to be amorphous in the 'as grown' condition. Films in the amorphous state have an index of refraction of 2.0 and can be etched easily (50 A/sec) in 0.5% HF. Annealing in air at 350C converts the film to the anatase tetragonal crystalline form and at 700C to a mixture of anatase and rutile. Both forms are quite etch resistant, but the anatase can be etched by HF and warm H2SO4. At 1000C, the film is completely rutile with an index of refraction of 2.5. This form is extremely etch resistant even in 120C H2SO4 (1000 A/hour). The conversion from amorphous to rutile is accompanied by a thickness decrease of 36%. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 15, 1970
- Accession Number
- AD0713845
Entities
People
- Eugene T. Fitzgibbons
- William H. Hartwig
Organizations
- University of Texas at Austin