PROTECTIVE BARRIER LAYER FOR SEMICONDUCTOR DEVICE ELECTRODES

摘要

A semiconductor device includes a die with at least one electrode on a surface thereof, at least one solderable contact formed on the electrode, and a passivation layer formed over the electrode and including an opening that exposes the solderable contact. The passivation layer opening may be wider than the solderable contact such that a gap extends between the contact and the passivation layer. The device also includes a barrier layer disposed on the top surface of the electrode, and along the underside of the solderable contact and across the gap. The barrier layer may also extend under the passivation layer and may cover the entire top surface of the electrode. The barrier layer may also extend along the sidewalls of the electrode. The barrier layer may include a titanium layer or a titanium layer and nickel layer. The barrier layer protects the electrode and underlying die from acidic fluxes found in lead-free solders.