Fabrication of integrated optical elements using a computer-controlled electron beam

A computer-controlled electron beam has been used to fabricate complex thin film waveguide structures in an electron resist (polyphenylsiloxane). The machine uses an interferometric substrate positioning technique to enable covering macroscopic distances. Elements fabricated include straight and curved guides, triangular transition elements, directional couplers, and resonant ring structures between straight guides. Typical guide widths are 5 or 10 micro with lengths ranging up to several centimeters. Losses (2 to 5 dB/cm at 6328 A) are primarily due to scattering by localized proturberances, which should be possible to eliminate.