Important applications of dielectric films used in modern integrated circuit technology include dielectric insulation, surface passivation, diffusion masking, radiation resistance, and hermetic seal. These many functional applications pose stringent requirements on the various properties of the insulating films and the methods used for their preparation. To date silicon dioxide (SiO2) has been used almost exclusively because of 1) its ease of preparation, 2) its well-understood properties, and 3) its generally good compatibility and satisfactory interface with silicon. There are, however, drawbacks to the use of SiO2and other materials have been sought for better performance, greater versatility, higher reliability, and lower cost. These include binary metal oxides and silicon nitride. The state of the art of thin film dielectric materials for microelectronics is reviewed in this paper. The role of thin film dielectrics for devices is presented, and new and known materials are discussed for potential applications.