| 摘要 |
PROBLEM TO BE SOLVED: To provide a thin film forming method capable of producing a gradient film using a target other than a dielectric target and without using plural target materials, capable of easily changing the refractive index without requiring a large scale device by controlling the flow rate ratio of the gas species to be introduced to change the compositional ratio of nitrogen, oxygen and fluorine and capable of producing an optically suitable thin film without reducing the density of the film, and to propose a thin film material by the forming method. SOLUTION: In this thin film forming method employing a sputtering device, a metallic target 109 is used. At least two or more kinds of a gaseous nitride, gaseous oxide and gaseous fluoride are introduced into a vacuum vessel 1 at the time of film formation, and the flow rate radio of each gas is continuously or stepwise controlled and changed, by which the refractive index of the compd. film is continuously or stepwise controlled. |
