METHOD FOR REMOVING POLYCRYSTALLINE SILICON PROTECTING LAYER ON IGBT BACK FACE HAVING FIELD TERMINATION STRUCTURE

摘要

Disclosed is a method for removing a polycrystalline silicon protecting layer (12) on an IGBT back face having a field termination structure (10). The method comprises thermally oxidizing the polycrystalline silicon protecting layer (12) on the IGBT back face until the oxidization is terminated on a lattice oxygen layer (11) located on the polycrystalline silicon protecting layer (12) to form a silicon dioxide layer (13), and removing the formed silicon dioxide layer (13) and the lattice oxygen layer (11) by a dry etching method. The method for removing the protecting layer is more easy to control.