Opto-Electronic Chip-on-Film Packaging Technology Using Low-CTE Fluorinated Polyimide Optical Waveguide Films

We have developed a new type of single-mode optical waveguide film with a low coefficient of thermal expansion (CTE). The low-CTE film was fabricated by sandwiching a fluorinated polyimide optical waveguide layer between low-CTE polyimide layers. Its CTE is less than one-tenth that of conventional polyimide optical waveguide films. We fabricated opto-electronic (OE) films with coplanar waveguide lines on the film surface using this low-CTE film. We confirmed that the film has good optical, electrical, and mechanical characteristics. This low-CTE OE film can be used to integrate optical and electrical devices on a film.