Patent ID: 8937386
Filing Date: 2015-01-20
Classification: H01L

Abstract:
1. A method for forming the conductive wire of a chip scale package, the chip scale package that is assembled on a substrate and is electrically connected with a plurality of solder points arranged at the substrate comprising: a die having a pad-mounting surface disposed with a plurality of bonding pads; at least one dielectric layer covered over the pad-mounting surface of the die; and at least one conductive wire arranged in the dielectric layer and one end of each conductive wire is electrically connected with one bonding pad of the die while the other end of the conductive wire extends outward and exposes outside surface of the dielectric layer to form a solder point that is electrically connected with a preset solder point on a substrate for connecting and assembling the die on the substrate; the method for forming the conductive wire of a chip scale package comprising the following steps: step 1: coating a first dielectric layer on the pad-mounting surface of the die; step 2: forming a slot on the first dielectric layer by exposure and development of photoresist materials while the slot corresponding to each bonding pad on the pad-mounting surface so that each bonding pad is exposed through each slot; step 3: coating an electrically conductive metal layer of nickel-gold materials by electroless nickel/immersion gold (ENIG) plating on each bonding pad in the slot; step 4: coating a second dielectric layer on the first dielectric layer and the conductive metal layer of nickel-gold materials of each bonding pad; step 5: forming a wiring slot on the second dielectric layer by exposure and development of photoresist materials while the wiring slot connects with each bonding pad and the slot of the bonding pad; each wiring slot is mounted concavely in the second dielectric layer; step 6: filling silver paste into each wiring slot by silver paste printing to form a respective conductive wire; step 7: removing by grinding the silver paste over the surface of the second dielectric layer so as to make the surface of the silver paste conductive wire formed and the surface of the second dielectric layer at the same level; step 8: coating an electrically conductive metal layer of nickel silver materials on each conductive wire; step 9: coating a third dielectric layer on the second dielectric layer and the electrically conductive metal layer of nickel silver materials of each conductive wire; step 10: forming a slot on the third dielectric layer by exposure and development of photoresist materials and the slot connected with one end of each conductive wire; and step 11: filling electrically conductive metal into each slot to form a respective solder point that is exposed outside the third dielectric layer to be electrically connected with each bonding pad of the die.