Semiconductor structure with enhanced withstand voltage

A semiconductor structure including a substrate, a buffer layer, a superlattice formed on the buffer layer, the superlattice including a pattern including n layers made of different materials, n being at least equal to 2, each layer including an AlxGayInwBzN type material where x+y+w+z=1, the thickness of each layer being less than the critical thickness thereof, the number of patterns being at least equal to 50, an insert layer wherein the material has a first lattice parameter, a layer of GaN material, wherein the lattice parameter is greater than the first lattice parameter such that the layer of GaN material is compressed by the insert layer.