recesses between gate layer stacks are filled with a first electrically insulating material . cavities or voids are opened up during the removal of a portion of the first insulating material . these voids are filled during the application of a conductive layer and can then lead to short circuits . inventively , a layer for closing up voids is produced before the conductive material is applied , as a result of growing a second electrically insulating material onto the surface of the remaining first insulating material . this second insulating layer closes up voids that have formed in the first insulating material so that they can no longer lead to short circuits . in particular , voids that are difficult to gain access to and open out into side walls of contact holes can in this way be closed up in a simple manner .