Discussed in an assembly substrate used in a display manufacturing method for placing semiconductor light-emitting devices to predetermined positions thereof using an electric field and a magnetic field, the assembly substrate including: a base part; a plurality of pair electrodes extending in one direction and disposed in parallel on the base part; a dielectric layer disposed on the base part to cover the plurality of pair electrodes; and partition walls disposed on the dielectric layer and defining cells at predetermined intervals along the one direction of the plurality of pair electrodes so as to overlap portions of the plurality of pair electrodes, and the semiconductor light-emitting devices being placed into the cells, respectively, wherein at least one of a recess portion and a concave and convex portion is formed on an upper surface of each of the partition walls.