A method is provided that includes first etching a substrate according to a first mask. The first etching forms a first etch feature in the substrate to a first depth. The first etching also forms a sliver opening in the substrate. The sliver opening may then be filled with a fill material. A second mask may be formed by removing a portion of the first mask. The substrate exposed by the second mask may be etched with a second etch, in which the second etching is selective to the fill material. The second etching extends the first etch feature to a second depth that is greater than the first depth, and the second etch forms a second etch feature. The first etch feature and the second etch feature may then be filled with a conductive metal.