Grating fabrication and characterization method for wafers up to 2 in

Abstract In the present paper, we describe a laser halographic system to fabricate frst-order gratings with pitches from 190 to 250 nm, over the entire surface of 2 in epitaxial wafers. We present an operating procedure allowing good control of parameters that determine the mark/space ratio. The corrugation uniformity is measured by a mapping grating efficiency system. By using a buried guiding layer, we achieve good control of the coupling coefficient. An improvement of the fabrication yield for devices is shown by means of distributed feedback laser diodes results.