Optical waveguide comprising aluminium-phosphorus etch stop layer

摘要

An optical waveguide structure 1 comprising: a III-V semiconductor (e.g. gallium arsenide) substrate 2 (i.e. a base); a III-V semiconductor top layer 3 (e.g. a layer of gallium arsenide); and an etch stop layer 3 containing aluminium and phosphorus (e.g. aluminium indium phosphate or aluminium gallium phosphate tertiary semiconductor layers) sandwiched between the two III-V semiconductor layers; wherein the top layer comprises first 5 and second 6 spaced apart recesses extending through the top layer to the etch stop layer such that they define an optical waveguide 7 between them. The waveguide may be manufactured using a dry etch containing chlorine to etch the recesses 5 and 6.