A light source comprising a substrate (1) having a first side and an opposing second side, at least one recess (2) being arranged in said first side of said substrate, a circuitry (4) at least partly arranged on said substrate (1), and at least one LED (3) being arranged in said at least one recess (2) and connected to said circuitry (4) is provided. The surface of said at least one recess (2) is continuous and is physically separated from said second side by substrate material. By arranging the LED in such a recess in the substrate, cross talk between adjacent LEDs is reduced, a good mechanical stability of the light source is maintained, and the thermal path through the substrate is reduced.