A method for fabricating crystalline surface structures (4) on a template (1). The method comprises the steps of providing a template (1) into a reaction environment, wherein one or more elements (3) required for the formation of the crystalline surface structure (4) are contained within the template (1); heating the template (1) inside the reaction environment to increase the mobility of the element (3) within the template (1), and to increase the surface diffusion length of the element (3) on the template-environment interface; and activating the template (1) by altering the conditions within the reaction environment, to make the mobile element (3) slowly migrate towards the template-environment interface and to make the element (3) organize on the surface of the template (1) as a crystalline structure (4).