Planarized contact plug

摘要

Initially, a conductive structure 104 is formed on a semiconductor substrate 100 having a plurality of diffusion regions therein. A first insulating layer 106 is formed over the semiconductor substrate 100 including the conductive structure 104. The first insulating layer is etched using a contact hole forming mask to form a contact hole 108. A conductive layer 110 is formed on the first insulating layer 106, filling up the contact hole 108 with the conductive layer 110. The conductive layer is etched until an upper surface of the first insulating layer is exposed. A second insulating layer 112 is formed over the first insulating layer 106. A contact plug 110a free of void can be formed and simultaneously a substrate surface is planarized by planarization-etching the second and first insulating layers.