The present invention discloses a substrate configured to receive a plurality of micro elements on a carrier board. The substrate comprises a body, a first conductive bump, and a second conductive bump. The body has a first surface, a transfer area is defined within the first surface, and a central portion and a peripheral portion is defined within the transfer area. The first conductive bump, disposed on the central portion, has a first volume. The second conductive bump, disposed on the peripheral portion, has a second volume. Wherein the first volume is different from the second volume.