PREPARATION AND ELECTROCHROMISM OF RF-SPUTTERED TIO2 FILMS

Titanium oxide (TiO2) thin films were prepared by rf-sputtering in an Ar/O-2 atmosphere from a compressed powder TiO2 target and their elect rochromic (EC) phenomena were investigated. Films prepared under the s puttering pressures of 1.3; 4.0 and 6.7 Pa were confirmed by X-ray dif fraction to be in amorphous state; anatase form and rutile form: respe ctively. Amorphous and anatase films showed cathodic FC properties. Th e maximum value of coloration efficiency was 14 cm(2)/C for the amorph ous films in an electrolyte solution of 1N HCl. AC conductance measure ments were measured from 110Hz to 100kHz for various oxygen contents i n the sputtering atmosphere. The ac conductance gradually decreased wi th increasing oxygen content in the region of up to 30% and was indepe ndent of oxygen content iri the region of more than 30%. In the films prepared in the sputtering atmospheres of oxygen contents of less than 30%, electronic conduction is interpreted to occur due to lack of oxy gen. In the films prepared in oxygen contents of 30% and more on the o ther hand; only ionic conduction is considered to exist.