Role of energy in low-temperature high-rate formation of hydrophilic TiO{sub 2} thin films using pulsed magnetron sputtering

Journal Article · Sun Jul 15 04:00:00 EDT 2007 · Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films

DOI:https://doi.org/10.1116/1.2736680· OSTI ID:20979488

Musil, J; Sicha, J; Herman, D; Cerstvy, R ^[1]

---

1. Department of Physics, University of West Bohemia, Univerzitni 22, 306 14 Plzen (Czech Republic)

The article reports on low-temperature high-rate deposition of hydrophilic TiO{sub 2} thin films using dc pulse dual magnetron (DM) sputtering in an Ar+O{sub 2} mixture on unheated glass substrates. DM is operated in a bipolar asymmetric mode and is equipped with Ti (99.5%) targets 50 mm in diameter. Main attention is concentrated on the investigation of the effect of an energy delivered to the TiO{sub 2-x} film, growing on unheated and heated substrates, by the ion bombardment on its structure. The effect of the length and shape of the pulse on the structure and deposition rate a{sub D} of the film is investigated in detail. It is shown that (1) the shortening of the pulse length to about {approx}2 {mu}s strongly enhances the ion bombardment of electrically insulating film which makes it possible to form nanocrystalline strongly hydrophilic TiO{sub 2} films at low ({approx}100 deg. C) values of the substrate temperature T{sub s} and (2) the increase of a repetition frequency f{sub r} of pulses results in a strong increase of a{sub D}; a{sub D} increases almost two times when f{sub r} is increased from 100 to 300 kHz. It was found that (1) hydrophilic TiO{sub 2} films several hundred nanometers thick are crystalline and can be sputtered on unheated glass substrates with a high deposition rate a{sub D}=80 nm/min at substrate surface temperatures T{sub surf}{>=}180 deg. C when f{sub r}=350 kHz is used and (2) hydrophilic TiO{sub 2-x} films sputtered at low values of the substrate surface temperature T{sub surf}{approx_equal}100 deg. C exhibit nanocrystalline structure and can be formed if much lower deposition rates a{sub D}{<=}5 nm/min are used. Correlations between the hydrophilicity of TiO{sub 2-x} film, its structure, T{sub surf}, process parameters, and the film deposition rate a{sub D} are given. A summary of the present state of knowledge in this field is presented.

• OSTI ID: 20979488
• Journal Information: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films, Journal Name: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films Journal Issue: 4 Vol. 25; ISSN 1553-1813
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTALS
DEPOSITION
GLASS
ION BEAMS
KHZ RANGE 100-1000
MAGNETRONS
MIXTURES
NANOSTRUCTURES
PULSES
SPUTTERING
SUBSTRATES
SURFACES
TEMPERATURE RANGE 0065-0273 K
THIN FILMS
TITANIUM OXIDES