Localized ohmic contact through a passivation dielectric for solar cell rear surface design

摘要

We report the demonstration of a method for forming localized ohmic contact through dielectric passivation layers, via a laser doped region, with no etching prior to metal deposition. A simple bench top voltage source contacted to the gate and bulk of a test Metal-Insulator-Semiconductor device facilitates localized heating leading to ohmic contact formation. The surface passivation qualities of the dielectrics are preserved away from the contact region using this method, as hard dielectric breakdown is restricted to the laser doped region. This is a potential technique for precisely contacting rear surface of high efficiency solar cells.