In this article, techniques for the realization of exactly positioned nanostructures are presented and the properties of nanometer scale optic laser devices based on GaInAs/GaInAsP/InP heterostructure are discussed. The fabrication of nanometer scale optic devices requires the precise control of the confinement length of carriers as well as the confinement length of photons, which are different by one order of magnitude. Both requirements can be met by the application of high resolution electron beam lithography in combination with low damage etching techniques and planar epitaxial overgrowth. Lateral structures down to 15 nm with high optical quality at periods around 240 nm suitable for distributed feedback (DFB) devices have been obtained. For the first time, these nanofabrication techniques allow the realization of a new class of semiconductor lasers : gain coupled wire and dot DFB lasers. The reduced dimensionality of the active area shows significant improvements of the gain values and the laser thresholds. The precise definition of dot arrays (array size up to some 100 mu m) allows the fabrication of a new device : a gain coupled dot DFB laser, consisting of dots forming a two-dimensional DFB grating.