Modifications to the spanning tree algorithm allow bad news to propagate quickly by providing that protocol entities on bridges process inferior information sent by the designated bridge for each LAN. In one preferred embodiment, a memory array is provided comprising a plurality of memory cells, each memory cell comprising a memory element comprising a switchable resistance material configurable to one of at least three resistivity states. An oxide layer may be formed on a second area of the substrate while preventing or reducing an oxidation of the nitride layer by a radical oxidation process in which oxygen radicals react with the second area of the substrate and the blocking layer in the first area of the substrate.