Contact Holes With Slotted Conductor for Eliminating Aluminum Spikes
Original Publication Date: 1984-Sep-01
Included in the Prior Art Database: 2005-Feb-05
It is proposed that the design of the first metallization of chips be modified such that the contact holes are covered only partly with aluminum and the air can reach the aluminum and silicon surfaces for their passivation. Silicon oxide/silicon nitride double layers are being used on a large scale for passivating silicon wafer surfaces, because their isolating properties are superior to those of single layers. However, such double layers have the disadvantage that the undercut occurring during the wet etching of the contact holes may lead to the formation of a nitride overhang and a cavity in the bottom layer.