Excimer laser ablation method and apparatus for microcircuit fabrication

摘要

A pulsed beam from an excimer laser is used for precision ablation of cadmium telluride (CdTe) and other materials to fabricate and delineate devices in electronic microcircuit structures. The fluence of the beam may be adjusted to selectively remove one constituent of the material, such as cadmium vs. tellurium, at a higher rate than the other constituent, while maintaining the integrity of the material surface. The beam may selectively remove an epitaxial layer of CdTe, CdZnTe, or HgCdTe from a GaAs substrate. The beam may be directed through a projection mask and optical system onto a material to form an image for patterned ablation. The optical system may focus an image of the mask on the material to form vertical sidewall patterns, or slightly defocus the image to form curved sidewall patterns and/or concave and convex lens structures for optical arrays.