A method for growing at least one III/V nano-ridge on a silicon substrate in an epitaxial growth chamber. The method comprises: patterning an area on a silicon substrate thereby forming a trench on the silicon substrate; growing the III/V nano-ridge by initiating growth of the III/V nano-ridge in the trench, thereby forming and filling layer of the nano-ridge inside the trench, and by continuing growth out of the trench on top of the filling layer, thereby forming a top part of the nano-ridge, wherein at least one surfactant is added in the chamber when the nano-ridge is growing out of the trench.