Method of forming an insulating structure having an insulating interlayer and a capping layer and method of forming a metal wiring structure using the same

摘要

In a method of forming an insulating structure, an insulating interlayer is formed on a substrate using a silicon source gas and a reaction gas. A capping layer is formed in-situ on the insulating interlayer by increasing a flow rate of an oxidizing gas included in the reaction gas so that the capping layer has a second thickness when the insulating interlayer is formed on the substrate to have a first thickness. The insulating structure dose not have an interface between the insulating interlayer and the capping layer so that the insulating interlayer is not subject to damage by a cleaning solution during a subsequent cleaning process, since the cleaning solution maynot permeate into the insulating structure. Additionally, leakage current is mitigated or eliminated between the insulating interlayer and the capping layer, thereby improving the reliability of a semiconductor device including the insulating structure.