METHOD OF INTERCONNECTION FORMATION

摘要

PURPOSE: A method of metal interconnection is provided to prevent failure of device resulting from erosion. CONSTITUTION: Impurity is added to oxygen plasma to reduce accumulative charges in exposed metal plug(200). The amount of the impurity is more than that of oxygen. The plasma(220) containing oxygen and impurity is used to eliminate a photoresist layer(218). After the elimination, the wet cleaning process in which alkaline solution is used follows. During the processing, the exposed metal plug(206) that loses charges does not easily wear off. Therefore, contact resistance between the metal plug(206) and metal line(210) does not increase due to erosion. Another way for erosion prevention is that one should eliminate the photoresist layer(218) out of the plasma(220) containing oxygen and treat the exposed metal plug(206) with pure water vapor plasma.