Abstract: Formulations and processes for forming wafer coat layers are disclosed. In one embodiment, an organic surface protectant is incorporated into a wafer coat formulation deposited onto a semiconductor wafer prior to the laser scribe operation. Upon removal of the wafer coat layer, the organic surface protectant remains on the bumps and thereby prevents oxidation of the bumps between die prep and chip and attach. In an alternative embodiment, an ultraviolet light absorber is added to the wafer coat formulation to enhance the wafer coat layer's energy absorption and thereby improve the laser's ability to ablate the wafer coat layer. In an alternative embodiment, a conformal wafer coat layer is deposited on the wafer and die bumps, thereby reducing wafer coat layer thickness variations that can impact the laser scribing ability.

Abstract: Formulations and processes for forming wafer coat layers are disclosed. In one embodiment, an organic surface protectant is incorporated into a wafer coat formulation deposited onto a semiconductor wafer prior to the laser scribe operation. Upon removal of the wafer coat layer, the organic surface protectant remains on the bumps and thereby prevents oxidation of the bumps between die prep and chip and attach. In an alternative embodiment, an ultraviolet light absorber is added to the wafer coat formulation to enhance the wafer coat layer's energy absorption and thereby improve the laser's ability to ablate the wafer coat layer. In an alternative embodiment, a conformal wafer coat layer is deposited on the wafer and die bumps, thereby reducing wafer coat layer thickness variations that can impact the laser scribing ability.