DIFFRACTIVE STRUCTURES HOLOGRAPHICALLY RECORDED IN AMORPHOUS HYDROGENATED CARBON (A-C-H) FILMS

We propose and demonstrate the direct recording of submicrometer relie f gratings in amorphous hydrogenated carbon (a-C:H) films by reactive ion etching (RIE) for use as diffractive optical components. The high refractive index of this film and its transparency in the IR make such structures promising candidates for IR-transmission diffractive optic al components. The structures are holographically recorded in photores ist and then transferred to a thin aluminum layer that is used as a ma sk for RIE of the a-C:H films. The diffraction measurements of the str uctures recorded in these films demonstrated the feasibility of using the materials as diffractive optical components. (C) 1997 Optical Soci ety of America.