A biocompatible fastener particularly well-suited for use in fundoplication procedures. For this purpose, during a sputtering process carried out in a vacuum chamber 18, reaction products 14 are incorporated at least virtually exclusively in the transition layer 12 on the substrate. A spring within the housing presses the plunger pieces toward the narrow end of the bore, with the spring located between the plunger pieces and a back plate that closes off part of a wide end of the tapered bore. The jaw members connect to a source of electrosurgical energy such that the opposable sealing surfaces are capable of conducting electrosurgical energy through tissue held therebetween. In some embodiments, a global-routing graph can further be extracted from a detailed routing graph.