Variable Depth Contact Hole Preparation Utilizing a Nucleation Layer and Selective Chemical Vapor Deposition for Stud Formation
Original Publication Date: 1986-Jun-01
Included in the Prior Art Database: 2005-Mar-09
This article describes a selective chemical vapor deposition (CVD) method for filling contact holes of various depths. In general, deposition techniques which depend upon film growth from bottom to top provide irregular topologies when they are utilized as a means of fabricating interconnection studs in contact vias having different depths. Specifically, the shallow vias will be filled before the deeper vias. While conformal blanket depositions and etch-back techniques fill holes of various depths, the etch-back process is hard to control and leaves steps in the topology. Shown in Fig. 1a is a technique for growing studs by first preparing a contact hole for the CVD process by application of a monolayer of bondable linkages on all of the exposed surfaces.