Achieving mass fabrication of microoptical systems by combining deep-x-ray lithography, electroforming, micromolding, and embossing

The paper reviews the application of deep X-ray lithography in conjunction with electroforming, plastic molding, and stamping (LIGA) for a mass production of micro- and submicron-structured photonic devices. LIGA technology offers almost total design freedom in lateral structuring and a high aspect ratio of 100. Vertical walls with heights up to 1 mm and optical grade surfaces enable their use as functional optical surfaces. It is possible to process a variety of materials such as metals and different polymers, including those with nonlinear optical properties. Therefore, Y-branches, couplers, and structures for the positioning and fixing of fibers, detectors, and light emitters can be integrated on one chip to build up hybrid optoelectronic devices.