Patent ID: 7666797

Claim:
A method for forming a semiconductor construction, comprising: providing a substrate which includes a semiconductor material base, a plurality of electrical nodes supported by the base, a plurality of upwardly-opening containers of conductive material extending upwardly from the nodes, and insulative material between the containers; the insulative material including, in ascending order from the base, a first silicon nitride-containing layer, a first sacrificial oxide, a second silicon nitride-containing layer, a second sacrificial oxide, and a third silicon nitride-containing layer; forming an opening through the third silicon nitride-containing layer to the second sacrificial oxide; removing at least some of the second sacrificial oxide to expose at least a portion of the second silicon nitride-containing layer; exposing the conductive material and second silicon nitride-containing layer to an etch which penetrates through the second silicon nitride-containing layer but does not remove at least the majority of the conductive material from the containers; the first sacrificial oxide being exposed through the penetrated second silicon nitride-containing layer; removing the exposed first sacrificial oxide; and wherein the third silicon nitride-containing layer is exposed during said removal of the second sacrificial oxide, and further comprising: after the removal of second sacrificial oxide, forming protective oxide over the third silicon nitride-containing layer; and protecting the third silicon nitride-containing layer with the protective oxide during the etch utilized to penetrate the second silicon nitride-containing layer.