REDISTRIBUTED WAFER LEVEL CHIP SIZE PACKAGE HAVING CONCAVE PATTERN IN BUMP PAD AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A redistributed wafer level chip size package(WLCSP) having a concave pattern in a bump pad is provided to increase a junction area and improve adhesion, by forming a concave pattern in a bump pad area to make a joint surface become rough. CONSTITUTION: A semiconductor chip includes a semiconductor substrate and a plurality of chip pads(54) exposed to a gap between passivation layers(56) formed on the semiconductor substrate. The first polymer layer(58) is formed on the passivation layer. The first under barrier metal(UBM)(60) of a predetermined pattern is formed on the chip pad and the first polymer layer. A redistributed lane(64) is formed on the first UBM, electrically to the chip pad, including a concave pattern. The second polymer layer(74) is formed on the first polymer layer and the redistributed lane, and defines a region of a bump pad exposing a part of the concave pattern and the redistributed lane. The second UBM(78) is formed on the bump pad. A solder bump(80) is formed on the second UBM, electrically connected to the redistributed lane. A joint surface of the bump pad and the solder bump is made rough by the concave pattern formed inside the region of the bump pad.