DEPOSITION OF SILICON OXINITRIDE FILMS FROM HEXAMETHYLDISILIZANE (HMDS) BY PECVD

Silicon oxinitride films are of great industrial interest due to their singular electrical, optical and mechanical properties. The interest in obtaining these films from liquid sources is greatly increasing bec ause of the lower harmfulness and of the new potential features that c an be obtained from the precursor chemical structure. Thin films of si licon carbo-oxi-nitrides have been deposited by PECVD from a liquid so urce, hexamethyldisilazane, and different mixtures of oxygen and ammon ia. We have investigated the effects of the variations in the composit ion of the reactant gases and in the applied power levels, on the visi ble and infrared optical and micromechanical properties. The refractiv e index can be varied continuously from 1.4 to 1.8, the IR absorption in the 8-13 mu m region can be tailored to the desired shape, and the hardness and Young's modulus modified, depending on the deposition con ditions. (C) 1998 Elsevier Science S.A.