Laser Writing of Masks for Integrated Optical Circuits

Masks for integrated optics applications have been fabricated using a focused Argon laser beam to expose a photoresistcoated gold-chrome plate. Curved and straight line masks were written using a combination or precision motor-driven rotational and translational stages to move the coated plate under the focused laser beam. By varying the laser power and/or writing speed, directional coupler masks have been made 3-µm wide separated by as little as 1 µm. From the results it is shown that narrow lines several centimeters long with better than 1000Å edge roughness can be obtained by this fabrication technique.