led dies are mounted a single submount tile . the led dies have a light emitting top surface . a uniformly thick layer of uv sensitive silicone infused with phosphor is then deposited over the tile , including over the tops and sides of the led dies . only the silicone / phosphor over the top and sides of the led dies is desired , so the silicone / phosphor directly on the tile needs to be removed . the silicone / phosphor layer is then masked to expose the areas that are to remain to uv light , which creates a cross - linked silicone . the unexposed silicone / phosphor layer is then dissolved with a solvent and removed from the tile surface . the silicone / phosphor layer may be defined to expose a wire bond electrode on the led dies . the tile is ultimately singulated to produce individual phosphor - converted leds .