Laser based dry etching of semiconductors offers a useful way of integrating patterning with growth for optoelectronic device development. In this article we demonstrate XeCl excimer laser based dry etching of InP. Experiments were carried out using a 10% gas mixture of chlorine diluted in helium. Studies were made of the effect of laser fluence on the etching process and how this influences pattern development. Based on these studies, surface electromagnetic waves were used to form ripple patterns and the optimum conditions for interference pattern development are reported, These studies show that a relatively low fluence is not conducive to pattern development. We also utilize diffraction from slits of different shapes in tandem with laser dry etching for the patterning of structures in semiconductors. This technique offers the potential to develop relatively damage-free structures. These structures may be suitable for devices used in a number of applications such as telecommunications.