METHOD OF DRY ETCHING FOR PATTERNING REFRACTORY METAL LAYER IMPROVED IN ETCHING RATE ANISOTROPY AND SELECTIVITY TO SILICON OXIDE

摘要

The high melting point metal layer on the silicon oxide layer is patterned by exposure to an etching gas containing SF ₆ , Cl, and CO, the F radical and the Cl radical effectively etch the high melting point metal, and the reaction product of the CO gas is transverse to the dry etching. It is possible to achieve good anisotropy, high etching rate and high selectivity to silicon oxide dry etching by not proceeding in the direction.