Method for fabricating semiconductor device with deposition cycles of chemical vapor deposition process to form composite contact structure

Abstract

The present application discloses a method for fabricating a semiconductor device. The method includes forming a first dielectric layer on a substrate; forming an expanded hole in the first dielectric layer; conformally forming an adhesive layer in the expanded hole by a first chemical vapor deposition process; conformally forming a first conductive layer on the adhesive layer by a second chemical vapor deposition process; and forming a first conductive structure on the first conductive layer by a third chemical vapor deposition process. The adhesive layer, the first conductive layer, and the first conductive structure together configure a composite contact structure. The second chemical vapor deposition process includes an initial deposition step and subsequent deposition cycles repeated until the first conductive layer is formed to a predetermined thickness.