In reactive sputtering of titanium target in the oxide mode, oxygen atoms are selectively sputtered from the target surface, which leads to a significant reduction of deposition rate of TiO
2 films. Utilizing this phenomenon, we developed a sputtering type oxygen radical source. Combining this oxygen radical source with a titanium sputtering source which is operated in metal mode, we showed that a high rate deposition of TiO
2 films above 40 nm/min was achieved. In addition, it was confirmed that the crystal structure of the film (anatase and/or rutile) was easily controlled by the control of the amount of oxygen radicals and titanium atoms incident on the substrate surface. Low temperature deposition of crystallized TiO
2 films was also attempted by using this sputter-deposition method. As a result, it was found that deposition of a well crystallized TiO
2 films on unheated substrate could be realized by using crystallized TiO
2 seed layer and a proper ion bombardment.
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